• Pedro da Fonseca (1528-1599)
• Benito Pereira (Benedictus Pereirus) (1535-1610)
• Diego de Zúñiga (1536-1597)
• Rudolf Göckel (Goclenius) (1547-1628)
• Francisco Suárez (1548-1617)
• Gabriel Vasquez (Vazquez) (1549-1604)
• Diego Mas (Didacus Masius) (1553-1608)
• Cristóbal de los Cobos (1553-1613?)
• Jacob Lorhard (1561-1609)
• Clemens Timpler (1563/4-1624)
• Cornelius Martini (1568-1621)
• Bartholomäus Keckermann (1572-1609)
• Francisco de Araujo (1580-1664)
• Johann Heinrich Alsted(1588-1638)
• Joannes a sancto Thoma (John Poinsot) (1589-1644)

After rejecting opinions which bold that the subject of metaphysics is God, Aristotelian 'separate substances', or Being in the categories, Fonseca says that the first and adequate subject of metaphysics is Being -- in so far as it is common to God and creatures (In libros Metaphysicorum IV c.1 q.1 s.3).

Understood in this way, Being is analogous, although as said of species within one genus or of individuals within one species it is univocal. Between God and creatures, between created substance and accidents, between different classes of accident, and between real Being and Being of reason, Being is analogous by analogies both of proportion and of attribution.

As God is related to his Being, so in proportion a created substance is related to its Being. Likewise, as created substance and its Being are related, so in proportion is an accident related to its Being. Again, as one kind of accident is disposed to its existence so is each other kind of accident to its existence. And as real beings are disposed to their Being, so beings of reason are to theirs (Metaphysicorum IV c.2 q. l s.5, 7). An analogy of attribution obtains among accidents as an analogy of two things to a third (that is, created substance), while between accidents and substance it is analogy of one to the other.

The same is true of beings of reason among themselves and then in comparison with real Being; for beings of reason do not depend less upon real beings than do accidents upon substance. Again, a creature is Being only by attribution or reference to God. Pursuing this, Fonseca distinguishes between formal and objective concepts. A formal concept is an 'actual likeness' (actualis similitudo) of a thing that is understood, produced by the intellect in order to express that thing. An objective concept is that thing is understood in so far as it is conceived through the formai concept. Both the formal and the objective concept of Being are one, but not perfectly so for the reason that they do not prescind perfectly from the concepts of the members which divide Being.

Being as such is transcendent as are also the concepts of thing, something, one, true and good (Metaphysicorum IV c.2 q.2 s.1, 4-5; q.5 s.2).

In God alone there is a perfect identity of essence and existence. In every creature, essence is distinct from existence, but not as one thing from another. Rather, says Fonseca, a created essence is as distinct from its existence as a thing from its ultimate intrinsic mode. In this opinion, he tells us, he is following Alexander of Hales and Duns Scotus ( 12) (Metaphysicorum, IV c.2 q.3 s.4). It is possible that here Fonseca has also to some extent anticipated the Suárezian doctrine of modes.

Excluded from the subject of metaphysics are accidental beings (entia per accidens) and beings of reason. An accidental being, in the sense excluded, is a juxtaposition of two or more beings which lack any (intrinsic) relation to one another (Metaphysicorum IV c.1 q.1 s.3).

Beings of reason are those which exist only inasmuch as they are objects of understanding. Within such beings of reason, as they stand in contrast with mind-independent real beings, Fonseca distinguishes proper Being of reason from one which is fictitious. Properly taken, a being of reason is one whose Being depends upon the understanding in such way that it can still be said of real beings, for example, the concepts of genus, species, and the like. A fictitious being as such is a being whose essence depends upon the understanding in such way that it cannot be said of any real being, for example, a chimera, a goat-stag, or the like (Metaphysicorum IV c.7 q.6 s.5).

• Institutionum Dialecticarum. Lisbon: 1564.
  Reprint: Instituições dialécticas. Institutionum dialecticarum libri octo - Introdução, estabelecimento do texto, tradução e notas por Joaquim Ferreira Gomes - Coimbra, Universidade de Coimbra, Instituto de Estudos Filosóficos, 1964 (2 voll.).
• Commentariorum in Libros Metaphysicorum Aristotelis.Rome: 1577.
  Original edition in 4 volumes (1615-1629) reprinted in 2 volumes: Hildesheim, Geog Olms, 1975.
  Vol. I: Rome, 1577; Vol. II: Rome, 1589; Vol. III: Évora, 1604; Vol. IV: Lyon, 1612; (reprint: Cologne Voll. I-III, 1615; Vol. IV 1629).
  Reprint of 1615-1629 edition: Commentarii in libros metaphysicorum Aristotelis Stagiritae- Hildesheim, Georg Olms, 1964.
• Isagoge Philosophica.Lisbon: 1591.
  Reprint: Isagoge Filosófica- Coimbra, Universidade de Coimbra, Instituto de Estudos Filosóficos, 1965.
  
  Latin text and English translation by João Madeira in Appendix to his Ph. D. thesis: Pedro da Fonseca's Isagoge Philosophica and the Predicables from Boethius to the Lovanienses (2006)

1. Pedro da Fonseca. Revista Portuguesa de Filosofia 9 1953.
   
2. Ashworth Earline Jennifer, "Petrus Fonseca and material implication," Notre Dame Journal of Formal Logic 9: 227-228 (1968).
   Abstract: I intend to show that the sixteenth century Jesuit, Petrus Fonseca, whose Institutionurn Dialecticarum libri octo (1564) was one of the most popular textbooks of the period, was well acquainted with [material implication].
   Fonseca introduces the subject in his discussion of the appropriateness of the name hypothetical' as applied to compound propositions."
3. Ashworth Earline Jennifer. Petrus Fonseca on objective concepts and the analogy of Being. In Logic and the workings of the mind. The logic of ideas and faculty psychology in early modern philosophy. Edited by Easton Patricia A. Atascadero: Ridgeview 1997. pp. 47-63
   Abstract: Petrus Fonseca was a Portuguese Jesuit who lived from 1528 to 1599. He was one of those responsible for drawing up the Jesuit Ratio Studiorum which set the curriculum for Jesuit schools across Europe, and he was also responsible for initiating the production of the Coimbra commentaries on Aristotle, or Conimbricenses, which served as texts for many schools and universities in the seventeenth century. He was himself the author of two popular texts, an introduction to logic, and a commentary on Aristotle's Metaphysics. His logic text was one of two alternatives prescribed by the Ratio Studiorum of 1599, and may have been used at La Flèche; his Metaphysics commentary was used at many Jesuit schools, and may also have been used at La Flèche.
   In short, Fonseca was a leading figure in the Scholastic Aristotelian tradition of the late sixteenth century, a tradition which lies behind many of the developments in early modem philosophy, and which in many ways is more important than the humanist tradition represented by Petrus Ramus.
   I have chosen to discuss Fonseca on objective concepts and the analogy of Being both because an examination of these issues will help us to understand how logic came to be bound up with the philosophy of mind and because the history of how these issues were treated helps solve a small problem about Descartes's sources. My paper has four parts. I shall begin by giving a historical outline of treatments of analogy and their relevance to Descartes. Secondly, I shall discuss late medieval theories of signification, particularly as they appear in Fonseca, in order to show how logicians turned away from spoken language to inner, mental language. Thirdly, I shall explain how it was that analogy, as a theory of one kind of language use, was particularly bound up with the discussion of concepts. Finally, I shall look at the distinctions Fonseca made while discussing the concepts associated with analogical terms." p. 47 (notes omitted)
4. Coxito Amândio Augusto, O universal lógico em P. da Fonseca e no Curso Conimbricense in Revista Filosófica de Coimbra 13: 299-324 (2004).
5. Doyle John P. Fonseca, Pedro da (1528-1599) in Routledge Encyclopedia of Philosophy. Edited by Craig Edward. New York: Routledge 1998. pp. 688-690 Vol. III
6. Felipe Donald. Fonseca on Topics in Studies on the history of logic. Proceedings of the III Symposium on the history of logic. Edited by Angelelli Ignacio and Cerezo Maria. Berlin: Walter de Gruyter 1996. pp. 43-64
7. Ferreira da Silva Custódio Augusto. Teses fundamentais da gnoseologia de Pedro da Fonseca. Lisboa: Tipografia da União Gráfica 1960.
8. Ferreira Joaquim Gomes, Pedro da Fonseca, sixteenth century Portuguese philosopher in International Philosophical Quarterly 6: 632-644 (1966).
   
9. Madeira João, Pedro da Fonseca's Isagoge Philosophica and the Predicables from Boethius to the Lovanienses, Leuven University, 2006.
   Contains in Appendix the Latin text and an English translation of Fonseca's Isagoge Philosophica.
10. Madeira João, Bibliografia de e sobre Pedro da Fonseca in Revista Filosófica de Coimbra 15: 195-208 (2006).
    
11. Martins António Manuel, Fonseca e o objeto da Metafísica de Aristóteles in Revista Portuguesa de Filosofia 38: 460-465 (1982).
12. Martins António Manuel, A metafísica inacabada de Pedro da Fonseca in Revista Portuguesa de Filosofia 47: 517-533 (1991).
    Abstract: This paper starts from the fact that the fourth volume of Fonseca's Commentariorum in Metaphysicorum Aristotelis Stagiritae libros (CMA) contains no quaestiones to Met. XII. An analysis of several explicit remissions to topics and questions to be developed in the context of that Artistotelian script (Met. XII), made by Fonseca in several places in volumes I, II and III of his CMA, reveals that his project was, from the beginning, to develop in the IV volume the subjects related to the philosophical discourse about God, divine attributes, omnipotence and freedom, contingency as well as to the separate substances. This indicates clearly that the metaphysics of Fonseca remained unfinished given the fact that the text on an important thematic cluster was not published notwithstanding the inclusion of such text in the original project of Fonseca. It is sustained that this fact should be taken in due consideration in any global interpretation of Fonseca's thought as well as in any comparison with other (finished) ontologies. Suárez is the most obvious case but not the only one."
13. Martins António Manuel, Lógica e ontologia em Pedro da Fonseca. Lisboa: Fundaçao Calouste Gulbenkian 1994.
    Indice Geral: 0. Introdução 9; 1. A obra de Fonseca 15; 2. Determinação do objecto da metafisica 61; 3. Essência e existência 191; 4. Transcendentais e categorias 235; 5 O principio de não contradição 345; 6. Conclusâo 371 Bibliografia 377-386.
    English Abstract: The aim of the dissertation is to show the place of Fonseca's work in the history of ontology. Starting with a close analysis of the texts connected with the core of classical metaphysics it is argued that the Commentarii in libros metaphysicorum Aristotelis far reacher than a mere textual commentary of Aristotle's text and represent one of the rare efforts to bring out a real synthesis of the main theoretical problems and questions emerging in the context of the aristotelian project of a first philosophy. This systematic work is carried out in the second half of the sixteenth century, just before the beginning of modern philosophy. Chapter one is dedicated to a brief account of Fonseca's work in his historical context. The remaining chapters explores some of the central topics of Fonseca's ontology. Chapter two, after a brief discussion of the aristotelian project of first philosophy, follows the transformation of this project in Fonseca's text discussing in particular his analysis of the concept of Being under the heading ens commune and the meaning of the thesis of analogia entis as well as the distinction between a formal and an objective concept of being. In chapter three we discuss the question of the distinction between essence and existence in order to grasp the meaning of Fonseca's thesis of a modal distinction ex natura rei. Chapter four seeks to articulate Fonseca's interpretation of the classical doctrine of the transcendentals (unum, bonum, uerum). The wish to articulate the universality and transcendentality of the concept of Being has taken us to introduce the problem of the categories in this chapter and a brief historico-critical survey beginning in Aristotle and ending in Kant. Finally, chapter five discusses the meaning of the principle of non contradiction in Aristotle and in Fonseca.
14. Martins António Manuel. Tópica metafísica: de Fonseca à Suárez in Francisco Suárez (1548-1617). Tradiçao e Modernidade. Edited by Cardoso Adelino, Martins António Manuel, and Dos Santos Leonel Ribeiro. Lisboa: Ediçoes Colibri 1999. pp. 157-168
15. Martins António Manuel, Pedro da Fonseca e a recepção da Metafísica de Aristóteles na segunda metade do séc. XVI in Philosophica: Revista do Departamento de Filosofia da Faculdade de Letras de Lisboa 14: 165-178 (1999).
    "It is claimed that in order to a better understanding of the reception of the text of the Metaphysics of Aristotle in the second half of the sixteenth century one must carefully distinguish the commentaries to the whole work from texts that treat particular questions. Although much work is still to be done, the great commentary of Pedro da Fonseca appears as the major original commentary to the Metaphysics produced during that period."
    
16. Romeo Luigi, Pedro da Fonseca in Renaissance semiotics: a segmental history of footnotes in Ars Semeiotica.An International Journal of Semiotics 2: 187-204 (1979).
17. Slattery Michael, Two Notes on Fonseca in Modern Schoolman 34: 193-202 (1957).
18. Slattery Michael, Fonseca on logical univocity in Modern Schoolman 34: 193-202 (1957).

The problem that continues to haunt the commentators [of Aristotle] is how to reconcile philosophia prima as universal scientia de ente with philosophia prima as theologia. The latter appears to be a special science rather than a universal one, since it studies one particular being (albeit the highest one), whereas the former studies being qua being. Aristotle had already recognised this problem and had come up with a solution that proved so cryptic that it provoked even more discussion. (26)

In the sixteenth and seventeenth centuries this discussion received an entirely new impulse in Protestant metaphysics. Although the early reformers had a very low opinion of Aristotelian metaphysics, by the end of the sixteenth century their successors had taken to writing textbooks on Aristotle's Metaphysics which copied the model of earlier commentaries. In fact, the Protestant scholasticism that emerged from the middle of the sixteenth century onwards drew heavily on the great Commentaries of the Counter Reformation, notably the ones composed by the Spanish Jesuits.(27) Faced with the institutional problem of how to teach theology and philosophy, the Protestant masters turned back to systematic Aristotelian philosophy of the familiar kind.(28) Moreover theological contorversies within Lutheranism and between Lutheranism and Calvinism "made precise definitions of terms like 'substance' and 'accident, 'nature' and 'person' absolutely imperative. (29)

This fuelled a keen interest in Aristotelian metaphysics. The Protestants were trying to construct a metaphysics conceived as a universal science of Being, a scientia de ente. This meant the removal of all the heterogeneous elements of Aristotelian metaphysics that could only with difficulty be combined with this "pure" science of Being. Hence we find in most Protestant metaphysics a marked tendency to separate natural theology from metaphysics as a science of being qua being. Therefore, by separating true metaphysics as a universal science of Being from natural theology as a scientia particularis, the ubiquitous problem of the subject matter of metaphysics was solved. The first to make this separation in the sixteenth century was actually a Jesuit, Benito Pereira (c 1535-1610). (30) His solution was taken up in various ways by Protestant scholastics, both Calvinist and Lutheran, such as Nicolaus Taurellus (1547-1606), Abraham Calov (1612-1686) and Rudolphus Goclenius the Elder (1547-1628). This tradition was not an isolated German phenomenon but also spread to England. By distinguishing between "first" or "summary philosophy" and natural theology. Francis Bacon clearly draws on this tradition as well.

• De communibus omnium rerum naturalium principiis et affectionibus libri quindecim. Qui plurimum conferunt ad eos octo Aristotelis qui de physico auditu inscribuntur, intelligendos. Rome: 1576.
  Commentary on Aristotle's Physics; reprinted Paris, 1579; Lyon, 1585; Cologne, 1595.
  The first edition (Roma, 1562) was titled: Physicorum sive De principiis rerum naturalium libri XV.

1. Blackwell Constance, Thomas Aquinas against the Scotists and Platonists. The definition of ens Cajetano, Zimara, Pererio 1495-1576 in Verbum.Analecta Neolatina 6: 179-188 (2004).
   Abstract: Thomas Aquinas is usually studied as a metaphysician, this is not the reading given to him by three Renaissance philosophers. At the turn of the sixteenth century there were at least two schools of Thomists, one influenced by Avicenna and Scotus, and the other influenced by Averroes, a reading of Aristotle and Thomas Aquinas himself. The discussion below traces how the interpretation of Thomas' De ente et essentia was changed from being a text for metaphysics to one used for physics. One of the meanings of ens - Being was as a term that was coterminous with the object. As a result, the debate over the first thing thought or the De primo cognito debate centered around the meaning for the term ens, the following essay demonstrates how it moved from metaphysics to physics."
   
2. Blum Paul, Benedictus Pererius: Renaissance culture at the origins of Jesuit science in Science and Education 15: 279-304 (2006).
   Abstract: Benedictus Pererius (1535-1610) published in 1576 his most successful book De Principiis, after he had taught philosophy at the Roman College of the Jesuits. It will be shown that parts of this book are actually based on his lectures. But the printed version was intended as a contribution to the debate within his Order on how science should be conceived. Pererius redefined the meaning of scientific speculation to the effect that metaphysics was split into ontology and natural theology, and that further speculative sciences, such as physics, gained their own competence. Throughout this book, as well as in his warning against magic and in his commentaries on the Bible, the Jesuit addresses Renaissance strains of neo-Platonism, Aristotelianism, and syncretism.
3. Rompe Elisabeth Maria, Die Trennung von Ontologie und Metaphysik. Der Ablösungsprozess und seine Motivierung bei Benedictus Pererius und anderen Denkern des 16. und 17. Jahrhunderts. Bonn: Rheinische Friedrich-Wilhelms Universität 1968.

• Philosophiae prima pars, qua perfecte et eleganter quatuor scientiae Metaphysica, Dialectica, Rhetorica et Physica declarantur, ad Clementem octavum Pontificem maximum. Toledo: 1597.
  Partial Spanish translation: Metafísica (1597) - Introducción, traducción y nota de Gerardo Bolado - Pamplona, Eunsa 2008.

1. Diego de Zúñiga, La Ciudad de Dios 212 (1999).
   Contents: Modesto González Velasco: Fray Diego de Zúñiga (1536-ca.1598): biografía, escritos y bibliografía: 5-57; Victor Navarro Brotons: La recepción de la obra de Copérnico en la España del siglo XVI: el caso de Diego de Zúñiga: 59-104; Gerardo Bolado Ochoa: La "Física" de Diego de Zúñiga OSA: 105-147; Lera San José: Javier, Fray Diego de Zúñiga OSA, "In Iob commentaria", 1584: 149-182.
2. Arámburu Cendoya Ignacio, Diego de Zúñiga, biografía y nuevos escritos (I) in Archivo Agustiniano 55: 51-103 (1961).
3. Arámburu Cendoya Ignacio, Diego de Zúñiga, biografía y nuevos escritos (II) in Archivo Agustiniano 55: 329-384 (1961).
   
4. Bolado Ochoa Gerardo, Fray Diego de Zúñiga O.S.A.: una filosofía como enciclopedia de las ciencias y las artes en el siglo XVI in Revista Agustiniana (Madrid) 26: 105-150 (1985).
5. Bolado Ochoa Gerardo, La unión de los estudios filosóficos y retóricos en la Enciclopedia de fray Diego de Zúñiga (1536-1599?) Aproximación a la "Retórica" in Revista Agustiniana (Madrid): 557-587 (1989).
6. Bolado Ochoa Gerardo, La "Fisica" de Diego de Zúñiga, OSA in La Ciudad de Dios 212: 105-147 (1999).
   
7. Bolado Ochoa Gerardo, Fray Diego de Zúñiga, OSA (1536-ca. 1598). Una aproximaciòn biogràfica. Madrid: Revista Agustiniana 2000.
8. Bolado Ochoa Gerardo, Presentación de la "Dialéctica" de Diego de Zúñiga (1536 ca.-1598) in Revista Agustiniana (Madrid): 465-500 (2003).
9. Gallego Salvadores Jordan, La aparición de las primeras metafísicas sistemáticas en la España del XVI. Diego Mas (1587), Francisco Suárez y Diego de Zúñiga (1597) in Escritos del Vedat 3: 91-162 (1973).
   
10. Gallego Salvadores Jordan, La metafísica de Diego de Zúñiga (1536-1597) y la reforma tridentina de los estudios eclesiásticos Estudio Agustiniano 9: 3-60 (1974).
11. González Velasco Modesto, Fray Diego de Zúñiga (1536 - c. 1598): biografía, escritos y bibliografía in La Ciudad de Dios 212: 5-57 (1999).

Goclenius is best described as a protestant Scholastic', his most important contribution to the metaphysics being terminological. He is the first philosopher to use the word ontologia [in Greek] to describe general metaphysics. Strangely enough, this word does not appear in the Isagoge, but rather in the Lexicon . Still, his use of the word precedes that of Calovius by 23 years, and that of Jean-Baptiste Duhamel by 65 [Raul Corazzon pointed out that the term "ontologia" was coined by Jacob Lorhard in 1606].

Although he does not use the term ontologia in the Isagoge, Goclenius does distinguish general metaphysics from special metaphysics in this work and a fortiori stood the concept of general metaphysics. The distinction between general and special metaphysics is not Goclenius's invention, however. The Spanish Jesuit Benito Pereira (c. 1535-1610) had already made it by 1562 (see Rompe Die Trennung von Ontologie und Metaphysik. Der Ablösungsprozess und seine Motivierung bei Benedictus Pererius und anderen Denkern des 16. und 17. Jahrhunderts1968, pp. 7-13) and an earlier manuscript making the distinction has been found (Zimmermann Ontologie oder Metaphysik. Die Diskussion über den Gegenstand der Metaphysik an 13. und 14. Jahrundert 1965, p. 60).

Both Wundt and Vollrath seem to have discovered the distinction between general and special metaphysics only in the Praefatio of Goclenius's Isogoge and have remarked that this distinction does not appear in the main text of the work. This is incorrect, however. The second part of the Isagoge is a series of disputations, the first of which, entitled De ente Communi, ad omnes Categorias conseguente discusses this distinction (Rompe is aware of this and hers is at present the most trustworthy account of Goclenius's work) Goclenius says that some divide first philosophy (prima philosophia), which is usually called 'metaphysics', into two parts. The first is universal and studies the most general notion of Being common to all things (de Ente in communi). The second part is particular and deals with God, divine spirits (daemones), and disembodied intellect (intellectus separatus a corpore, p. 126). Goclenius ascribes this view to Aristotle and then goes on to say that he prefers to divide things up differently. Knowledge (scientia) should be divided into a universal and a particular part, and the universal part should be called 'first philosophy'. The particular part in turn should be divided into a 'transnatural' part which deals with God, and a 'natural' one, which deals with natural entities (pp. 126-7).

Goclenius's idea of knowledge, then, has a particular part which seems to contain every specific science. In contrast, Perera includes only theology, 'spiritology', and psychology, and Christian Wolff only theology, psychology, and cosmology, within special metaphysics. Thus Goclenius is proposing a way of cutting up the sciences such that prima philosophia is truly cast in the role of the queen of the sciences, lording over them all as the scientia universalis. On the face of it, Goclenius's taxonomy of metaphysics is more reasonable than that of Wolff or Pereira. If one is going to take seriously the notion of a 'superscience' which studies the most abstract idea of Being which the objects of all specific sciences share, then one is compelled, I think, to include all of the particular sciences within specific metaphysics. This is true unless, of course, one has platonic misgivings about the possibility of being able to have knowledge about substances which have matter mixed up in them. However, a good Scholastic, wedded as he is to the spirit of Aristotle, has no such misgivings.

Thus the Marburg professor Rudolph Goclenius in the preface to his Isagoge in primam philosophiam (1598), spoke of two separate sciences, a universal science called 'first philosophy' and a particular science called 'metaphysics'. First philosophy deals with Being, its properties and its principles; metaphysics studies the various types of immaterial being: God, the intelligences and the human soul.

• Problemata Logica Marburg: 1591.
  Reprint: Frankfurt, Minerva, 1967.
• Physicae disputationes in septem libros distinctae Frankfurt: 1592.
  Partial translation in German: Rudolphus Goclenius - Disputationen zur Natur-Wissenschaft 1592 - Translated with introduction, notes and name index by Hans Günther Zekl - Würzburg, Königshausen & Neumann, 2007.
• Isagoge in Peripaticorum et scholasticorum primam philosophiam, quae dici consuevit Metaphysica. Frankfurt: 1598.
  Reprint: Hildesheim, Georg Olms, 1976.
  Translated in German: Rudolphus Goclenius - Isagoge. Einführung in die Metaphysik 1598 - Translated with introduction, notes and an essay on the author by Hans Günther Zekl - Würzburg, Königshausen & Neumann, 2005.
• Conciliator philosophicus. Cassellis: 1609.
  Reprint: Hildesheim, Georg Olms, 1977
• Lexicon philosophicum quo tanquam clave philosophiae fores aperiuntur. Frankfurt: 1613.
  Reprint: Hildesheim, Georg Olms, 1964 (with the Lexicon philosophicum Graecum )
• Lexicon graecum Philosophicum Marburg: 1615.
  Reprint: Hildesheim, Georg Olms, 1964 (with the Lexicon philosophicum quo tanquam clave philosophiae fores aperiuntur )
  
• Metaphysica exemplaris Wittenberg: 1625.

Francisco Suárez (1548-1617)

INTRODUCTION

Perhaps the most important enterprise of the Doctor Eximius, the Disputationes Metaphysicae is a complete résumé of his own and previous Scholastic thought on a myriad of questions, arranged in the form of fifty-four "Disputations" dealing with various topics systematically.

In format, Suárez's Disputationes represented a radical departure from previous metaphysical treatises. Until its appearance, metaphysics had been explicitly treated either just incidentally in the form of Opuscula ("little works"), such as St. Thomas Aquinas's De ente et essentia ("On Being and Essence"), or in commentaries on the text of Aristotle. Both methods were clearly unsatisfactory, the one incomplete and the other shackled to the rambling obsolete order of Aristotle. So Suárez says that he intends to give, preparatory to theology, a complete exposition of metaphysics which, instead of following the text of Aristotle, will proceed in a systematic fashion.

In executing his intention, the Doctor eximius has divided his work into two main parts, to which correspond two tomes. After explaining in the first Disputation the object, the dignity, and the utility of metaphysics, he proceeds in the first part to treat of Being in general, its properties and causes. In the second tome, he descends to items under Being, considering them from a metaphysical viewpoint.

The first part studies the concept of Being (Disputation 2) which, representing in some way everything that entails an order to existence, transcends all genera, species and differences. It will encompass everything real, from extrinsic denominations, through mere possibles, to the subsistent, purely actual, and necessary reality of God. Following this is a treatment of the essential properties of every being inasmuch as it is a being, namely, unity, truth and goodness. Under the discussion of unity, space is given to questions concerning the principle of individuation (Disputation 5), the reality of universal natures (Disputation 6), and the various kinds of distinction (Disputation 7). The discussion of truth (Disputation 8) is balanced by discussion of falsity (Disputation 9) and that of goodness (Disputation 10) by that of evil (Disputation 11) After the essential properties, there follows a consideration of the causes of Being. Disputation 12 treats causes in general while Disputations 13-25 deal with various types of causes. Concluding this first part, Disputation 26 presents a comparison of causes with their effects and Disputation 27 considers the mutual relations of causes one to another.

The second part opens with the division of Being into infinite and finite (Disputation 28). Infinite Being, or God, is the subject of the next two Disputations. In Disputation 29, the existence and unicity of God is demonstrated metaphysically. Disputation 30 goes on to investigate, as far as unaided human reason can, the divine perfection, simplicity, immensity, immutability, wisdom, and omnipotence. With Disputation 31 Suárez begins his treatment of finite Being. It is this Disputation which is the locus of the famed Suárezian denial of the real distinction between essence and existence in creatures. In Disputation 32, Suárez considers the distinction of substance and accident in general. Substance is treated in metaphysical detail through the next four Disputations while the different categories of accident are the subject matter of Disputations 37 to 53. The fifty-fourth Disputation, ... concludes the whole work with a discussion of "beings of reason" including negations, privations, and reason-dependent relations -- all of which fall outside real Being, the object of metaphysics.

It is generally agreed that modern philosophy places greater stress on the subjectivity of the knower than on the objective reality of the known, as does medieval philosophy. Suárez, when faced with a basic problem of metaphysics, whether the concept of Being is one or multiple, decided, without any Scholastic precedent, to make a subjective state of mind (conceptus formalis entis) the criterion for establishing the unitary sense of objective reality (conceptus obiectivus entis). When problems like that of Being became too difficult to resolve by the usual medieval objective" approach, Suárez recommended recourse to the "subjective" because it was better known (notior) to us than the objective, especially as the subjective is produced "by us and in us" (a nobis et in nobis). On the basis of the principle that "to one formal concept one objective concept necessarily corresponds" uni conceptui formali unus conceptus obiectivus necessario respondet, Suárez, as never before in Scholasticism, made extra-mental reality dependent for its truth on in intra-mental concept, thus changing the main thrust of medieval philosophy. Descartes adopted the same approach when faced with he basic problem of his system, of establishing, through the resources of the intellect, knowledge that was objectively certain. Like Suárez, he made an intra-mental concept the criterion for determining extra- mental reality. The intra-mental concept was the thinker's "cogito"; the extra-mental reality was the thinker's existence, "sum"; with the certainty of the existence following as a necessary consequence, "ergo", from the intra-mental concept itself.

Suárez could not have become the founder of modern philosophy before he had worked out his own system, the technical vocabulary of which provided the groundwork for the emerging modern systems. This vocabulary was first needed to systematize metaphysics. The long subjection to the unmethodical text of Aristotle had delayed the attainment of this important philosophical object, realised at last in the Disputationes Metaphysicae.

In the two volumes of that great work, the philosophy of Being was given a binary structure, characterized, though not by its author, as general (vol. 1) and special (vol. 2) metaphysics. General metaphysics has as its theme the common concept of Being, its general attributes, and its causes; and special metaphysics, the kinds of Being contained under the common concept, (*) classified in two dichotomies, the primary of finite and infinite, and the secondary of substance and accident. Suárez also furnished the burgeoning modern systems with vocabulary as groundwork for their ideas, in many cases the vocabulary anomalously grew to be alien to the system that was its source. How was this possible? Through that system undergoing anamorphosis, a condition where something distorted occasionally appears to be regular; indeed so regular, that the distorted ideas seem to belong to the nature of anamorphosed thing itself. Which may explain why the realist Suárez is made out to be a crypto-idealist, and it may be that the philosophies of realism (Scholasticism) and idealism (modern philosophies) have some hidden affinity and are closer together than one would suppose.

AN OVERVIEW OF SUÁREZ'S METAPHYSICAL DISPUTATIONS

The two large folio volumes of the Disputationes metaphysicae appeared in Salamanca in 1597. In his brief foreword, "Ad lectorem," Suárez indicates his reason for undertaking this project: It is impossible for anyone to become a competent theologian unless he builds upon a solid metaphysical foundation. He develops this view in the Prooemium or prologue to his work. The science of metaphysics, he holds, is indispensable for a mastery of theology. More intimately than any other human field of knowledge, it is connected with theology; it has for its object the most universal and supreme principles which embrace all Being and are the foundation of all knowledge. This function of metaphysics was for Suárez a compelling motive for interrupting his theological labors and producing, in one systematic, comprehensive work, the results of his metaphysical studies and investigations, begun many years before. The prologue reads as follows :

Sacred and supernatural theology relies on divine illumination and on principles revealed by God. However, it is cultivated by human reasoning and investigation, and therefore enlists the aid of truths naturally known, using them as ministers and instruments to develop its deductions and to illustrate divine truths. But of all the natural sciences, that which holds the primacy and has won the name of first philosophy is most valuable for promoting sacred and supernatural theology. For among them all it approaches most closely to the science of divine things, and also explains and vindicates those natural principles which embrace the universe of Being and in one way or another stand at the basis of all learning.

For this reason I wished to revise and expand what I have worked out for my students and publicly taught on various occasions during many years concerning this natural wisdom, so that the results of my reflections might be made available to the general public. Accordingly I am forced for a time to interrupt, or rather to postpone, the more weighty commentaries and disputations on sacred theology I am so busily engaged in, as well as the taxing labor required for their publication.

It often happened that while I was treating of divine mysteries, metaphysical problems would come up. Without a knowledge and understanding of these, the higher mysteries of Christianity can scarcely, if at all, be discussed as they deserve. Hence I had to mingle baser questions with supernatural subjects, a practice that is annoying to readers and is not very profitable for them; or else, to avoid this awkward procedure, I had briefly to propose my own opinion in such matters, and its demand of toy readers a blind faith in my judgment. This was embarrassing for me, and could well seem out of place to them. Metaphysical principles and truths are so closely interwoven with theological conclusions and deductions, that if knowledge and full understanding of the former are lacking, knowledge of the latter must necessarily suffer.

Led on by such considerations, I yielded to repeated requests and decided to write the present work. I have arranged all the metaphysical disputations according to a method calculated to combine comprehensive treatment with brevity, and so to be of greater service to revealed wisdom. Hence it will not be necessary to divide the work into several books. For all that pertains to this doctrine and is suitable to its subject matter in the light of the method adopted, can be fully handled in a limited number of disputations. What belongs to "pure philosophy" or dialectics has, so far as possible, been left out as not in keeping with the scope of the work. I shall adhere to this norm, even though I am aware that other writers on metaphysics devote much space to such subjects. But before I begin to treat of the subject-matter of this doctrine I shall, God willing, discuss wisdom or metaphysics itself, its object, use, necessity and its attributes and rewards.

The work falls into two main parts, coinciding with the two volumes in which it was published. It comprises fifty-four disputations in all. The first volume treats of metaphysics in its broadest comprehension: Being as such, and the properties and causes of Being. The first disputation deals with the object of metaphysics; the second inaugurates an exposition of the concept of Being. Disputations III to XI discuss the passions and transcendental properties of Being. Disputations XII to XXVII embody the author's doctrine on causes.

The second volume opens with a consideration of infinite and finite Being. Two disputations deal with natural knowledge of the existence, nature, and attributes of God. The remaining disputations are devoted to the metaphysics of finite Being, distributed according to the Aristotelian categories.

As the title indicates, the work is cast in the form of disputations. The discussions follow a regular pattern. First, the problem is stated. Then the various solutions that have actually been proposed by philosophers are reviewed (Variae opiniones). Thirdly, Suárez gives what he considers to be the true doctrine or, as the case may be, the most probable theory (Vera sententia or Resolutio quaestionis). A refutation of opposing views often brings the disputation to a close." pp. 6-7

An outline of the METAPHYSICAL DISPUTATIONS

THE OBJECT OF METAPHYSICS IN THE FIRST THREE DISPUTATIONS

In the twenty-seven Disputations which make up the first volume, Suárez is concerned with Being in general while, symmetrically, in the twenty-seven Disputations of the second volume he descends to particular Being -- in effect dividing metaphysics itself into a general and a special part.

In the very first Disputation (Opera omnia, Paris: Vivès [1856]: vol. 25, pp. 1-64), he tells us that the object of metaphysics is "Being insofar as it is real Being". Explaining this, in Disputation 2 (pp. 64-102) he uses two distinctions already familiar to Scholastic authors. The first is between the formal concept as an act of the mind and the objective concept as what is immediately the object of that act. This latter may be an individual thing or some common feature (ratio) of things. It may, further, be something mind-independent, whether actual or possible, or it may be something merely objective or mind-dependent. The second distinction is between Being as a participle, which refers to actual existents and "being" as a noun, which refers to whatever is not a simple fiction but is true in itself and apt really to exist. The object of metaphysics is then identified with the "common objective concept of being as a noun." This precise object, which reflects Avicenna's (980-1037) understanding of Aristotelian metaphysics, abstracts from existence and, as common, transcends all categories, genera, species and differences to embrace everything real. This last runs a range from extrinsic denominations (such as "being right," "being left," "being known," or "being willed"), 9 through mere possibles (which reduce to non-contradiction), to actual created substances and accidents, to the subsistent, purely actual, necessary, untreated, and infinite reality of God. Over this range, the common concept of being as a noun is analogous with what Suárez will call "an analogy of intrinsic attribution." In this analogy, a unified concept of being is shared, in an order that is intrinsic to it, by different beings (God and creatures, substance and accidents) in such way that the being of what is posterior depends upon and indeed "demands" (postulat) the being of what is prior.

Disputation 3 (pp. 102-115) offers a general treatment of the transcendental properties, namely unity, truth, and goodness, which belong to every being insofar as it is a being. " pp. XI-XII (notes omitted)

To what extent Suárez, despite his token references to Thomas Aquinas, follows Scotus' approach is evident from the definition of the subject matter of metaphysics in the first of the 54 disputations. Here he discusses six possible solutions to the problem, but dismisses all of them as either too comprehensive or too restrictive. The subject matter of metaphysics is neither everything that is knowable nor the "supreme real being" (Suárez, Disp. Met. 1.1.9), i.e. God or the immaterial being; nor is it the finite being that is the subject matter of physics. Rather, the subject matter of metaphysics is "being as such" (ens inquantum ens), i.e. a common determination (ibid. 1.1.23 and 26) that is grasped in a concept that abstracts from all categorial determinations as well as from being finite/infinite, being caused/uncaused, and being material/immaterial. Metaphysics is, therefore, the "most general science" (ibid. 1.5.14), because it treats of the "rationes universales transcendentales" (ibid. 1.2.27). That is to say, metaphysics is a scientia transcendens in the Scotistic sense. Because the immaterial being (God) cannot be known except through previously known transcategorial attributes of Being, metaphysics as transcendental science and metaphysics as theology coincide.

According to Suárez, metaphysics deals with the "formal" as well as the "objective" concept of Being. By the formal concept of Being, Suárez understands the act of knowing, which "ex unica et prima impositione" (ibid. 2.2.24) yields an intentional representation of the object; by the objective concept he designates that which is intentionally represented by that act. In other words, Suárez does not assume a theory of concepts characterized by a noetic-noematic parallelism of res and conceptus; rather he accepts Ockham's critical approach towards a strictly realistic interpretation of universal concepts. Since Scotus himself does not rely on that parallelism when it comes to the concept of Being, Suárez can substantially follow Scotus and apply Being to a first and unified formal concept which, in virtue of its imposition, represents a first and unified objective concept of absolutely simple content that grasps all different beings in an indeterminate way, i.e. as Being.

To the formal concept of Being there corresponds an appropriate and immediate objective concept, which is explicitly neither substance nor accident, neither God nor creature, but which designates these in a unified way, i.e. inasmuch as they are similar and agree in Being. (ibid. 2.2.8)

What does the objective concept that corresponds to the formal concept of Being mean? According to Suárez, it is a determination that transcends the generality of the genus; this determination cannot be defined, but only explicated through its relationship to actual existence. Being means "that which can exist" (id quod aptum est esse seu realiter existere: ibid. 2.4.7); the possibility of existence is grounded in an ontological disposition which (as we have seen before) appears in the non-contradiction of the internal contents constituting essences.

Because entity in the sense of being(ness) -- which in a concrete being is identical with the entity or being(ness) of that being -- is grasped indeterminately by the concept of Being, that concept has an "illimitability and transcendence" (ibid.2.6.10) on account of which it precedes all more determinate modes. First among those more determinate modes, according to both Suárez and Scotus, is the classification "finite/infinite", which Suárez understands in terms of "intensity"; this allows him to interpret finite Being as a non-determinate mode of an intensive quantity and infinite Being as the "totally indivisible infinity of perfection which in itself is most real and complete" (ibid. 30.2.25)." pp. 62-63.

EXCLUSION OF THE "BEINGS OF REASON" FROM THE SUBJECT OF METAPHYSICS

As every historian of philosophy knows, Aristotle thought the subject of metaphysics was "Being insofar as it is Being" and from this subject he excluded "being as true". Centuries after Aristotle, Francisco Suárez, S.J., designated the subject of metaphysics more explicitly as "Being insofar as it is real Being".

The addition of "real" to Aristotle's formula highlighted the inclusion of all that can as well as does exist (4). Against the backdrop of two already well known distinctions - (1) between formal and objective concepts, and (2) between being as a participle and being as a noun -- for Suárez the subject so conceived was identical with "the objective concept of being as a noun" (5). Concurrently, while being was said to be analogous with regard to hierarchically ordered objects (God and creatures, substance and accidents) with an intrinsic attribution of the perfection it represented (6), such analogy presupposed a common, unitary, and all but univocal, concept (7). But from that concept and from the subject of metaphysics Suárez excluded "beings of reason" (8), which he subsumed under Aristotle's Being as true (9), and of which impossible objects, in the sense of those that would be self-contradictory, furnished the paradigm case. (10) pp. 297-298

HEIDEGGER'S APPRECIATION OF SUÁREZ

Heidegger reserves the place of honor in his exposition [Of the Thesis of Medieval Ontology] for the Spanish Jesuit Francisco Suárez (1548-1617), a figure whose pre-eminence for Heidegger is both systematic and historical. Suárez is the bridge between the Middle Ages and the modern world (Grundprobleme der Phänomenologie 111-16/ English translation 79-83). It was through Suárez that the metaphysics of Scholasticism flowed into modern thinkers; his influence is clearly detectable in Descartes, Leibniz, Wolff, Schopenhauer, Kant, and Hegel. Suárez abandoned the format of the commentarium employed by the classical Scholastic thinkers and developed instead a strictly philosophical and systematic treatise entitled Disputationes Metaphysicae. Although it was written in the seventeenth century, it is the first major systematic Scholastic treatise on metaphysics (GP 112/80). St. Thomas' major works, for example, are either commentaries or, when they are systematic, theological treatises. The Disputationes is divided into fifty-four tracts. The first twenty-seven treat of metaphysica generalis (or ontologia); the next twenty-six treat of special beings (metaphysica specialis); the fifty-fourth is devoted to beings of reason (entia rationis). In general metaphysics, Suárez investigates the properties of the abstract concept of being in general. In special metaphysics, he investigates God and creatures, that is, infinite and finite beings. This distinction between general and special metaphysics was imported fully intact by Wolff and made its way to the center of Kant's architectonic -- to the distinction between the transcendental analytic and the transcendental dialectic -- in the Critique of Pure Reason.

The first Disputatio treats: De natura primae philosophiae seu metaphysicae, of the essence of First Philosophy or metaphysics. Suárez begins in the introduction (3) by discussing the various designations of metaphysics (varia metaphysicae nomina), and does so with independent recourse to Aristotle. Here he finds that metaphysics is designated as sapientia (sophia), prudentia (phronesis), then as prima philosophia (proté philosophia), then as naturalis theologia (theologiké) -- which Suárez here interprets in a sense quite unlike that of antiquity (quoniam de Deo ac divinis rebus sermonem habet, quantum ex naturali lumine haberi potest 4) – and finally as metaphysica.

Suárez says that this natural theology or First Philosophy is called metaphysics because it deals with God (ex quo etiam metaphysica nominata est 5). He thereby gives the expression a different meaning from that of Aquinas. Aquinas uses the expression metaphysica insofar as it treats de ente in communi. Suárez, on the other hand, says it is called metaphysics because it is theology. He remarks that this title 'metaphysics' does not stem from Aristotle himself, but from his interpreters (quod nomen non tam ab Aristotele, quam ab ejus interpretibus habuit 6). However, he is of the opinion that Aristotle did put together this collection.

He explains the expression 'metaphysics' in a sense that deviates from the explanation given by Aquinas, and brings in another point of view which is significant in the history of metaphysics: de his rebus, quae scientias seu res naturales consequuntur. (7)

The Metaphysics is not concerned, then, with such books as come after those about physics, rather 'coming after' is now taken in the sense of content: knowledge of the suprasensuous is later than that of the sensuous. In the order of appropriation, in the order in which knowledge of the suprasensuous arises, in the sequence of investigation, metaphysical knowledge is placed after knowledge of physics. Suárez stresses the méta in the sense of post and understands this post in the sense of the stages of knowledge proceeding from the sensuous to the suprasensuous. At the same time however he brings into play the interpretation in terms of content: méta, afterwards, that which comes afterwards, which exceeds the sensuous.

Suárez is the thinker who had the strongest influence on modem philosophy. Descartes is directly dependent on him, using his terminology almost everywhere. It is Suárez who for the first time systematized medieval philosophy and above all ontology. Before him the Middle Ages, including Thomas and Duns Scotus, treated ancient thought only in commentaries, which deal with the texts seriatim. The basic book of antiquity, Aristotle's Metaphysics, is not a coherent work, being without a systematic structure. Suárez saw this and tried to make up for this lack, as he regarded it, by putting the ontological problems into a systematic form for the first time, a form which determined a classification of metaphysics that lasted through the subsequent centuries down to Hegel.

In accordance with Suárez' scheme, distinctions were drawn between metaphysica generalis, general ontology, and metaphysica specialis, which included cosmologia rationalis, ontology of nature, psychologia, ontology of mind, and theologia rationalis, ontology of God. This arrangement of the central philosophical disciplines recurs in Kant's Critique of Pure Reason. Transcendental logic corresponds in its foundations to general ontology. What Kant deals with in transcendental dialectic, the problems of rational psychology, cosmology, and theology, corresponds to what modern philosophy recognized as questions. Suárez, who gave an exposition of his philosophy in the Disputationes Metaphysicae (1597), not only exercised great influence on the further development of theology within Catholicism but, with his order colleague Fonseca, had a powerful effect on the shaping of Protestant Scholasticism in the sixteenth and seventeenth centuries. Their thoroughness and philosophical level are higher by far than that which Melanchthon, for example, attained in his commentaries on Aristotle.

• Commentariorum in primam-secundae S. Thomae. Alcalà: 1598.
  Two volumes: second volume printed 1605.
• Commentariorum, ac disputationum in primam partem S. Thomae. Tomus primus. Complectens viginti sex quaestiones priores. Alcalà: 1598.
• Commentariorum in tertiam partem. Alcalà: 1609.
  Four volumes published 1609-1615.

1. Baldini Ugo. Ontology and mechanics in Jesuit scholasticism: the case of Gabriel Vazquez. In Scientiae et artes. Die Vermittlung alten und neuen Wissens in Literatur, Kunst und Musik. Vol. I. Edited by Mahlmann-Bauer Barbara. Wiesbaden: Harrassowitz 2004. pp. 99-142
2. Lapierre Michael J. The noetical theory of Gabriel Vasquez, Jesuit philosopher and theologian (1549-1604). His view of the objective concept. Lewiston: Edwin Mellen 1999.
   Contents: Foreword I; Preface III; Acknowledgements VII; Introduction 1; 1. Historical overview 5; 2. Life and times of Gabriel Vasquez 11; 3. Concept and external world 21; 4. Cocept and truth 35; Concept and knowledge 55; 5. Concept and Being 75; 7. Concluding observations 93; Appendix A. Chronological table of Vasquez's life 97; Appendix B. List of the writings of Gabriel Vasquez 99; Bibliography 103; Index of names and subjects 109.
3. Schmutz Jacob. Le miroir de l'univers: Gabriel Vazquez et les commentateurs jésuites. In Sur la science divine. Edited by Bardout Jean-Christophe and Boulnois Olivier. Paris: Presses Universitaires de France 2002. pp. 382-411

• Metaphysica disputatio de ente et eius proprietatibus. Valencia: 1587.
  Critical edition of the Latin text and Spanish translation with the title: Disputación metafísica sobre el ente y sus propiedades (1587) - Pamplona, EUNSA, 2003. Parte I: traducción castellana; Parte II: Original latino.
  Contains a reprint of the essay: El Maestro Diego Mas y su Tratado de Metafísca. La primera metafísica sistemática by Jordán Gallego Salvadores, pp. 17-88 (originally published in: Analecta Sacra Tarraconensia 43 (1970), pp. 3-92).

1. Bastit Michel, "De l'intérêt d'une lecture traditionnelle de saint Thomas: la question de l' esse chez Diego Mas," Revue Thomiste 104: 447-468 (2004).
   "Résumé. On essaie ici de tester sur un texte de Diego Mas la fécondité théorique d'une lecture traditionnelle thomiste, au sens de lecture au sein d'une école. À partir des questions concernant l'ordre de l'existence à la forme et à l'essence, on aperçoit progressivement que la rigoureuse procédure scolastique utilisée par l'auteur du texte reconduit son lecteur à la question elle-même, et le met ainsi en mesure d'être philosophe en acte. En outre cette rigueur permet à une pensée de ce type d'entrer en rapport avec les développements de la philosophie exacte moderne et contemporaine où se manifeste aujourd'hui un regain d'intérêt pour la métaphysique et l'ontologie que l'on aurait tort de négliger."
2. Gallego Salvadores Jordan, "El Maestro Diego Mas y su Tratado de Metafísica. La primera metafisica sistematica," Analecta Sacra Tarraconensia 43: 3-92 (1970).
   Reprinted in: Diego Mas, Disputación metafísica sobre el ente y sus propiedades - Edited by Santiago Orrego and Juan Cruz Cruz - Pamplona, EUNSA, 2003, pp. 17-88.

• Cristóbal de Los Cobos. In Metaphysicam por Cristóbal de Los Cobos, S. J. Salamanca, 1582-1583 (Ms. Inédito) (*). In Actas del IV Centenario del nacimiento de Francisco Suárez 1548-1948. Vol. I. Madrid: Dirección General de Propaganda 1948. pp. 375-41
  
  (*) De la colección de manuscritos estudiados durante los homenajes centenarios tributados al Doctor Eximio. (Edited by Eleuterio Elorduy).

Works by Jacob Lorhard

Other

Within three of his writings, Timpler notes that the study and knowledge of metaphysics is required for the study and knowledge of all other philosophical disciplines. For this reason, Timpler's Metaphysics textbook merits examination here prior to consideration of his other philosophical writings. The basic components of Timpler's Metaphysics textbook can be outlined as follows:

Timpler considers the subject matter of metaphysics to be everything which is intelligible to human beings; therefore, All that is Intelligible (omne intelligibile) is the all-inclusive category within which all component parts of Timpler's metaphysics are subsumed. Timpler divides the category All that is Intelligible into Something (aliquid) and Nothing (nihil). Each individual intelligible falls within one and only one of these two categories.

Timpler asserts that Nothing cannot be perfectly defined. His brief remarks concerning Nothing shall be presented within chapter 15 section 17 and within chapter 20 section 9. Timpler's "Something" (aliquid) is equivalent to "Being" (esse; est) in the broadest sense of the latter. Timpler's Being can be explained with the use of the following table:

Being (understood in its broadest sense) includes A and C yet excludes B.

The broadest and most basic distinction made within Timpler's Metaphysics textbook, therefore, is the distinction made between something (i.e., "Being" understood in its broadest sense) and Nothing (i.e., Non-Being). There is no medium between Something and Nothing; any given intelligible object falls into one and only one of these two categories. According to Timpler, these two categories are contradictorily opposed to one another. The principle which states this contradictory opposition--i.e., which states that it is absolutely impossible for an intelligible subject matter to be both Being and Non-Being simultaneously -- is the principle of contradiction; Timpler regards this principle to be indemonstrable and absolutely necessary. The principle of contradiction is the most important rule contained within Timpler's Metaphysics textbook; in so far as it comprises All that is Intelligible, it regulates the entire subject matter of that textbook.

Timpler also notes that the principle of contradiction is "that primary complex principle which is basic to all of the arts" (i.e., to both the liberal arts and the illiberal arts).

It must be emphasized that All that is Intelligible and the Principle of Contradiction (all sub-categories of the former are regulated by means of the latter) are the broadest, most general categories not only of Timpler's Metaphysics textbook, but of all of his other writings as well. These two categories embrace the entirety of Timpler's thought as expressed within his various philosophical writings. The study of metaphysics is basic to the study of all other disciplines partly due to the fact that it directly deals with these two general categories which are basic to every other discipline.

• Metaphysicae systema methodicum. Steinfurt: 1604 (Nine editions, including some unauthorized imprints (Steinfurt 1604, Lich 1604, Hanau 1606, Frankfurt a. M. 1607, Marburg 1607, Hanau 1608, Frankfurt a. M. 1612, Hanau 1612, Hanau 1616).

1. Freedman Joseph S. European Academic Philosophy in the Late Sixteenth and Early Seventeenth Centuries. The life, significance and philosophy of Clemens Timpler (1563/4-1624). Hildesheim: Georg Olms 1988.
   Two volumes.

• Metaphysica commentatio. Strasburg: 1605.
• De Analysi logica tractatus. Helmstedt: 1619.

1. Pozzo Riccardo, "Kornelius Martini: De natura logicae : Prolegomeni ad un corso di lezioni del 1599," Rivista di Storia della Filosofia 44: 499-527 (1989).
2. Pozzo Riccardo, "Res considerata and modus considerandi rem : Averroes, Aquinas, Jacopo Zabarella, and Cornelius Martini on reduplication," Medioevo.Rivista di Storia della Filosofia Medievale 24: 251-267 (1998).

• Systema logicae, tribus libris adornatum. Hannover: 1600.
• Scientiae metaphysicae compendium systema. Hanau: 1609.

1. Freedman Joseph S., "The career and writings of Bartholomew Keckermann (d. 1609)," Proceedings, American Philosophical Society 141: 305-364 (1997).
   Reprinted in: Joseph S. Freedman - Philosophy and the Arts in Central Europe, 1500-1700 - Aldershot, Ashgate, 1999 - Essay VII.
2. Muller Richard A., "Vera Philosophia cum Sacra Theologia nusquam pugnat. Keckermann on philosophy, theology and the problem of double truth," Sixteenth Century Journal 15: 341-365 (1984).
   
3. Zuylen Willem Hendrik van. Bartholomäus Keckermann. Sein Leben und Werk. Leipzig: R. Noske 1934.

• Commentaria in universam Aristotelis Metaphysicam tomus primus, quinque libros complectens. Salamanca: 1617.
  
• Commentaria in universam Aristotelis Metaphysicam tomus secundus, septem libros complectens a sexto usque ad duodecium inclusive. Salamanca: 1631.

1. Beuchot Mauricio Puente, "La doctrina tomista clásica del signo: Domingo de Soto, Francisco de Araujo y Juan de Santo Tomás," Critica 36: 39-60 (1980).
2. Beuchot Mauricio Puente. Metafísica. La ontología aristotélico-tomista de Francisco de Araújo. Ciudad de México: Instituto de Investigaciones Filosóficas UNAM 1987.
   
3. Fernández-Rodríguez José Luis. El ente de razón en Francisco Araújo. Pamplona: Ediciones Universidad de Navarra 1972.
4. O'Brien Chrysostom, "El enigma de Francisco de Araujo," La Ciencia Tomista 89: 221-234 (1962).
5. Wells Norman J. Francisco Araujo, O.P., on eternal truths. In Graceful reason. Essays in ancient and medieval thought presented to Joseph Owens C.SS.R. Edited by Gerson Lloyd P. Toronto: Pontifical Institute of Medieval Studies 1983. pp. 401-417

• Metaphysica tribus libris tractata per praecepta methodica. Herborn: 1613.
• Cursus philosophici Encyclopedia libri XXVI. Herborn: 1620.
  Vol. I Praecognita disciplinarum; II. Philologia; III. Philosophia theoretica; IV. Philosophia practica; V. Tres superiores facultates; VI. Artes mechanicae; VII. Farragines disciplinarum.
  
  Reprint of the 1630 edition: Encyclopaedia. Septem tomis distincta - Stuttgart, Frommann-Holzboog, 1989.
• Metaphysica exemplaris. Wittenberg: 1625.
• Alsted and Leibniz: on God, the magistrate, and the millennium. Edited by Antognazza Maria Rosa and Hotson Howard. Wiesbaden: Harrassowitz in Kommission 1999.
  Texts edited with introduction and commentary.

1. Hotson Howard. Johann Heinrich Alsted, 1588-1638: between Renaissance, Reformation, and universal reform. New York: Oxford University Press 2000.
2. Schmidt-Biggermann Wilhelm. Topica universalis: Eine Modellgeschichte humanistischer und barocker Wissenschaft. Hamburg: Meiner 1983.
   On Alsted see pp. 100-139.

• Christoph Scheibler (1589-1653)
• Johannes Micraelius (1597-1658)
• Sebastian Izquierdo (1601-1681)
• Bartolomeo Mastri (1602-1673)
• Juan Caramuel y Lobkowitz (1606-1682)
• Abraham Calov (1612-1686)
• Johannes Clauberg (1622-1665)
• Jakob Thomasius (1622-1684)
• Jean Baptiste Du Hamel (1624-1706)
• Jean Le Clerc (1657-1736)
• Johann Franz Budde (Buddeus) (1667-1729)
• Christian Wolff (1679-1754)
• Alexander Gottlieb Baumgarten (1714-1762)
• Christian August Crusius (1715-1775)
• Johann Heinrich Lambert (1728-1777)

1. Scheibler, Christoph. 1617. Opus Metaphysicum Duobus Libris Universum Hujus Scientiae Systema Comprehendens. Giessen.
   Second edition Oxford 1633; definitive edition in Opera philosophica: Metaphysica duobus libris universum huius scientiae systema comprehendens. Opus, tum omnium facultatum tum in primis philosophiae & theologiae studiosis utile & necessarium. Premissa est Summaria methodus, ... Frankfurt 1665.
2. ———. 1654. Opera Philosophica. Frankfurt.
   Four volumes (1654-1658): Opera philosophica ut sunt Opus logicum, quatuor partibus ... Opus metaphysicum, duobus libris ... Liber physicus de anima ... Adiectis ubique indicibus necessariis ... (reprinted 1665).

1. Pozzo, Riccardo. 2004. "Logic and Metaphysics in German Philosophy from Melanchton to Hegel." In Approaches to Metaphysics, edited by Sweet, William, 57-66. Dordrecht: Kluwer.
   On Scheibler see pp. 63-65.
2. ———. 2005. "Die Transzendentalienlehre Bei Christoph Scheibler." In Das Geheimnis Des Anfangs, edited by Neuser, Wolfgang and Reichold, Anne, 73-78. Bern: Peter Lang.
3. Roncaglia, Gino. 2003. "Modal Logic in Germany at the Beginning of the Seventeenth Century: Christoph Scheibler's Opus Logicum." In The Medieval Heritage in Early Modern Metaphysics and Modal Logic, 1400-1700, edited by Friedman, Russell L. and Nielsen, Lauge O., 253-308. Dordrecht: Kluwer.

1. Micraelius, Johannes. 1653. Lexicon Philosophicum Terminorum Philosophis Usitatorum. Jena.
   Revised edition: Stettin 1661 and 1662.
   Reprint with an introduction by Lutz Geldsetzer: Düsseldorf, Stern-Verlag Janssen & Co. 1966.

1. Canone, Eugenio. 1997. "I Lessici Filosofici Latini Del Seicento." In Il Vocabolario Della République Des Lettres. Terminologia Filosofica E Storia Della Filosofia. Problemi Di Metodo. Atti Del Convegno Internazionale in Memoriam Di Paul Dibon (Napoli, 17-18 Maggio 1996), edited by Marta, Fattori, 93-114. Firenze: Olschki.
2. Geldsetzer, Lutz. 1966. "Über Das Philosophische Lexikon Des Johannes Micraelius Und Die Philosophische Lexikographie." In Lexicon Philosophicum Terminorum Philosophis Usitatorum, I-XXII. Düsseldorf: Stern-Verlag Janssen & Co.
   Introduction to the anastatic reprint of the second edition (Stettin, 1662).

1. Izquierdo, Sebastian. 1659. Pharus Scientiarum. Lyon.

1. Ceñal, Ramón. 1974. La Combinatoria De Sebastián Izquierdo: "Pharus Scientiarum" (1659), Disp. Xxix, De Combinatione. Madrid: Instituto de España.
   Texto latino y traducción españols von una introducción: La Disputatio De Combinatione de Izquierdo en la historia de la aritmética combinatoria, desde Clavius a Bernoulli.
2. Di Vona, Piero. 1964. I Concetti Trascendenti in Sebastián Izquierdo E Nella Scolastica Del Seicento. Napoli: Loffredo.
3. Fuerte Herreros, José Luis. 1981. La Lógica Como Fundamentación Del Arte General Del Saber En Sebastián Izquierdo: Estudio Del Pharus Scientiarum (1659). Salamanca: Universidad de Salamanca, Instituto de Estudios Albacetenses.
4. Schmutz, Jacob. 2002. "Sebastián Izquierdo: De La Science Divine À L'ontologie Des États De Chose." In Sur La Science Divine, edited by Bardout, Jean-Christophe and Boulnois, Olivier, 412-421. Paris: Presses Universitaires de France.
   Traduction d'extraits de Le Phare des sciences pp. 422-435.

1. Mastri, Bartolomeo. 1646. Disputationes in Xii Libros Metaphysicorum. Venezia.
   2 volumes

1. Blum, Paul Richard. 2002. "La Métaphysique Comme Théologie Naturelle: Bartolomeo Mastri." Études Philosophiques:31-47.
2. Burkhardt, Hans. 1988. "Modalities in Language, Thought and Reality in Leibniz, Descartes and Crusius." Synthese no. 75:183-215.
3. Crowley, Bonaventure. 1948. "The Life and Works of Bartolomeo Mastri, O.F.M. Conv. 1602-1673." Franciscan Studies no. 8:97-152.
4. Forlivesi, Marco. 2002. Scotistarum Princeps: Bartolomeo Mastri (1602-1673) E Il Suo Tempo. Padova: Centro Studi Antoniani.
5. ———. 2002. "La Distinction Entre Concept Formel Et Concept Objectif Dans La Pensée De Bartolomeo Mastri." Études Philosophiques:3-30.
6. ———, ed. 2006. Rem in Seipsa Cernere. Saggi Sul Pensiero Filosofico Di Bartolomeo Mastri (1602-1673). Padova: Il Poligrafo.
   Con introduzioni di Alessandro Ghisalberti e Gregorio Piaia.
7. Knebel, Sven K. 2002. Entre Logique Mentaliste Et Métaphysique Conceptualiste: La Distinctio Rationis Ratiocinantis in Études Philosophiques:145-168.
   In the scholastic way of spelling out A = A, some sort of distinction intervened between the relata, viz. the distinctio rationis ratiocinantis. To distinguish between the distinctio rationis ratiocinatae and ratiocinantis was commonplace from the sixteenth up to the eighteenth centuries. But how to make sense of a distinction that is without any foundation in the object itself? Mastri's account marks a crisis within Scotism, since his reception of Peter Aureol's conceptualism made it possible to give the distinctio rationis ratiocinantis a metaphysical rather than a logical interpretation.

1. Caramuel y Lobkowitz, Juan. 1642. Rationalis Et Realis Philosophia. Louvain.

1. Dvorák, Petr. 2008. "Relational Logic in Juan Caramuel." In Mediaeval and Renaissance Logic, edited by Gabbay, Dov and Woods, John, 645-666. Amsterdam: North-Holland.
   Handbook of the History of Logic, vol. 2.
2. Pastine, Dino. 1975. Juan Caramuel. Probabilismo Ed Enciclopedia. Firenze: La Nuova Italia.
3. Schmutz, Jacob. 2001. "Juan Caramuel on the Year 2000: Time and Possible Worlds in Early-Modern Scholasticism." In The Medieval Concept of Time. The Scholastic Debate and Its Reception in Early Modern Philosophy, edited by Porro, Pasquale, 399-434. Leiden: Brill.
4. ———. 2006. "Juan Caramuel Y Lobkowitz (1606-82)." In Centuriae Latinae Ii. Cent Et Une Figures Humanistes De La Renaissance Aux Lumières, À La Mémoire De Marie-Madeleine De La Garanderie, edited by Nativel, Colette, 182-202. Geneva: Droz.
5. Serrai, Alfredo. 2005. 'Phoenix Europae'. Juan Caramuel Y Lobkowitz in Prospettiva Bibliografica. Milano: Sylvestre Bonnard.

His most interesting metaphysical works are the Metaphysica divina pars generalis and the Metaphysica divina pars specialis. Calovius's logical / epistemological works, the Gnostologia and Noologia, may be of some interest, although as logic the works are weakened by the psychologism which is often found in logic texts of that period and school.

Calovius is a good example of the typical Protestant metaphysician of the 17th century. According to Calovius, one's metaphysical studies should be guided by the truths of revealed faith, in this case orthodox Lutheranism. Without the guidance of the celestial light, all our travels into scholarly study are nothing more than pitiable wandering. But we cannot follow this celestial light unless we pay attention to both Scripture and nature. Calovius reveals himself to be a true scholastic by naming Aristotle the foremost philosopher. Thus, the main task of Calovius's work is to reconcile the revealed truths of orthodox Lutheranism with the principles of Aristotle's metaphysics. That one is so enabled to refute the errors of agnostic natural scientists, Socinians (a favourite target of Protestant attacks, this Protestant sect denied the doctrine of the Trinity and the divinity of Christ), Jesuits, Calvinists, and other heretics, so much the better. Still, both sources of knowledge are required: without Aristotelian natural science, there will be factual errors; without Scripture, heresy. (Hinc tot errores, tot haereses.)

Metaphysics, according to Calovius, is the wisdom of being qua being (sapientia Entis qua Entis). This definition should be understood as denoting one discipline, which is also called 'ontology' or 'transcendental wisdom' (ontologia [in Greek] sive transcendentalis Sapientia ). The usual and improper sense of 'metaphysics' adopted by the Jesuit Benito Pereira (c. 1535-1610) according to whom metaphysics is concerned with disembodied spirit, is rejected. Indeed, he says, they hallucinate who make the object of metaphysics either God or immaterial substance, and they plainly do not understand the nature of wisdom.

Thus, Calovius believes that the mistake of people like Pereira was to fail to acknowledge a notion of Being which is general enough to be common both to spiritual and material beings. This, of course, may not be entirely fair to Pereira and other Thomists, since theological discomfiture may arise from claiming that God and creatures are subsumed under a general concept of Being. Does this most general of concepts logically or ontologically precede God? Or is the dignity of God affected by sharing the notion of Being with beings like you and me?

Metaphysics, finally, must deal with what really is, not merely what could be. Calovius claims that truly and properly, metaphysics concerns itself with non-complex, essential, positive, real, actual Being (Ens incomplexum, per se, positivum, reale et actuale).

Only in an attenuated sense does it contain complex, accidental, deprived beings, beings of reason, and potential beings (Entia complexa, per accidens, privationes, Entia rationes et in potentia). Calovius prefers to limit metaphysics to the former, and we might not incorrectly cali him an 'actualist'. Atfer all, Calovius wonders, how does one abstract notion of Being common to actual and potential Being, if potential Being is not truly Being?"

1. Calov, Abraham. 1636. Metaphysica Divina, Pars Generalis. Wittenberg.
   Complete title: Metaphysica divina, a principiis primis eruta, in abstractione Entis repraesentata, ad S.S. Theologicam applicata, monstrans, Terminorum et conclusionum transcendentium usum genuinum abusum a hereticum, constans.
2. ———. 1651. Scripta Philosophica. Lubecca.
   Reprint Wittenberg 1673. Contents: I. Gnostologia; II. Noologia seu habitus intelligentiae; III. Metaphysicae divinae pars generalis; IV. Metaphysicae divinae pars specialis; V. Enciclopedia Mathematica; VI. Methodologia; VII. Ideae encyclopaedias disciplinarum realium.

1. Appold, Kenneth G. 1998. Abraham Calov's Doctrine of Vocatio in Its Systematic Context. Tübingen: Mohr Siebeck.

1. Clauberg, Johannes. 1647. Elementa Philosophiae Seu Ontosophia. Groningen.
2. ———. 1691. Opera Omnia Philosophica. Amsterdam.
   Reprint: Hildesheim, Georg Olms, 1968 (2 volumes).
3. ———. 2007. Logique Ancienne Et Nouvelle. Paris: Vrin.
   Traduction de la Logica Vetus et Nova (1658).
   Présentation, traduction et notes par Jacqueline Lagrée et Guillaume Coqui.

1. Balz, Albert G.A. 1934. "Clauberg and the Development of Occasionalism." Philosophical Review no. 43:48-64.
   Reprinted in: A. G. A. Balz, Cartesian Studies, New York, Columbia University Press, 1951, pp. 158-194.
2. Bardout, Jean-Christophe. 2002. "Johannes Clauberg." In A Companion to Early Modern Philosophy, edited by Nadler, Steven, 140-151. Malden: Blackwell.
3. Brosch, Pius. 1926. Die Ontologie Des Johannes Clauberg. Eine Historische Würdigung Und Eine Analyse Ihrer Probleme. Greifswald: L. Bamberg.
   Inaugural Dissertation.
4. Carraud, Vincent. 1999. "L'ontologie Peut-Elle Être Cartésienne? L'exemple De L'ontosophia De Clauberg, De 1647 À 1664: De L'ens À La Mens." In Johannes Clauberg (1622-1665) and Cartesian Philosophy in the Seventeenth Century, edited by Verbeek, Theo, 13-38. Dordrecht: Kluwer.
5. École, Jean. 1999. "La Place De La Metaphysica De Ente, Quae Rectius Ontosophia Dans L'histoire De L'ontologie Et Sa Réception Chez Christian Wolff." In Johannes Clauberg (1622-1665) and Cartesian Philosophy in the Seventeenth Century, edited by Verbeek, Theo, 61-74. Dordrecht: Kluwer.
   Réimprimé dans:Hans Werner Arndt, Sonia Carboncini-Gavanelli et Jean École (eds.), Autour de la philosophie Wolffienne, Hildesheim: Georg Olms, 2001, pp. 117-130.
6. Lagrée, Jacqueline. 2002. "Sens Et Vérité Chez Clauberg Et Spinoza." Philosophiques no. 29:121-138.
   This paper aims to show how the Spinozistic hermeneutical position in the Tractatus Theologico-Politicus is founded in a particular tradition, that of Johannes Clauberg, which makes a strong distinction among the sensus genuinus (i.e., the meaning intended by the author), the true meaning, and the truth. L. Meyer, a physician and friend of Spinoza, accepts this distinction but he reduces the true meaning to the truth as it is understood in the philosophy of Descartes or Spinoza. Spinoza, however, maintains the distinction between true meaning and truth, and for him the Bible keeps its holy character as long as it helps man to practice justice and charity. Human reason brings out the universal moral teachings of the Bible and it fosters a community of those who genuinely seek the truth.
7. Mancini, Italo. 1960. L'ontosophia Di Johannes Clauberg E I Primi Tentativi Di Soluzione Cartesiana in Festschrift H. J. De Vleeschauwer, 66-83. Pretoria: University of South Africa.
8. Savini, Massimiliano. 2006. L'invention De La Logique Cartésienne: La Logica Vetus Et Nova De Johannes Clauberg in Revue de Métaphisique et de Morale:73-88.
   The Logica vetus & nova published by Johannes Clauberg (1654) is directly inspired by the works of Descartes. For this reason, this text is commonly considered as the first handbook of 'Cartesian' logic. Which are, therefore, the Cartesian elements distinguishing this logic from the previous ones? Our aim is to show that there are two main aspects which Clauberg derives from the works of Descartes: on the one hand the foundation of logic on the perceptio clara et distincta; on the other the role of medicina mentis assumed by logic, on the basis of a philosophical theory of prejudices that has been derived from the Principia philosophiae (but also from Bacon). Clauberg's logic, anyway, does not accept the most radical innovations of Cartesian theory of knowledge: in this way it is still bound up with the scholastic tradition.
9. ———. 2011. Johannes Clauberg. Methodus Cartesiana Et Ontologie. Paris: Vrin.
10. Scheffel, Dieter. 1994. Zur Grundidee Der Ontologie Bei Wolff Und Clauberg in Aufklärung Und Erneuerung. Beiträge Zur Geschichte Der Universität Halle Im Ersten Jahrundert Ihres Bestehens (1694-1806), edited by Jerouschek, Günter and Sames, Arno, 157-162. Hanau: Dausien.
11. Trevisani, Francesco. 1993. Johannes Clauberg E L'aristotele Riformato in L'interpretazione Nei Secoli Xvi E Xvii. Atti Del Convegno Internazionale Di Studi Milano (18-20 Novembre 1991) Parigi (6-8 Dicembre 1991), edited by Canziani, Guido, 103-126. Milano: Franco Angeli.
12. Verbeek, Theo, ed. 1999. Johannes Clauberg (1622-1665) and Cartesian Philosophy in the Seventeenth Century. Dordrecht: Kluwer.
13. Viola, Eugenio. 1975. Scolastica E Cartesianesimo Nel Pensiero Di J. Clauberg in Rivista di Filosofia Neo-Scolastica no. 67:247-266.
14. Weier, Winfried. 2000. Leibnitiana Bei Johannes Clauberg in Studia Leibnitiana no. 32:21-42.
    It is a much neglected fact that the young Leibniz expressed particular interest for the philosophy of Johannes Clauberg, a follower of Descartes with Aristotelian outlook who taught at the University of Duisburg. Indeed he found here, against the background of Cartesianism, important impulses and preconceptions for important basic positions of his, which in many respects can be understood as extensions and unfoldings of Claubergian approaches. In this way nothing less than a story of creation and development of Leibnizian thought is uncovered, e. g. from the gnoseological (symbolism of ideas; differentiation of nominal and real definitions, truths of reason and fact; the importance of real existence for the coherence of concepts) to the ontological area (the preparation of Leibnizian monadology through the question about the character of Being in the innate ideas of Descartes; development of the concept of potency by means of that of facultas to that of virtus, of the petites perceptions of Leibniz and accordingly, for the first time in intellectual history, to his basic understanding of the unconscious): Further development of the anthropological question formulation through the idea of pre-established harmony.

1. Thomasius, Jakob. 1665. Schediasma Historicum. Leipzig.
2. ———. 1670. Erotemata Metaphysica Pro Incipientibus. Accessit Pro Adultis Historia Variae Fortunae Quam Methaphysica Experta Est. Leipzig.
   Reprint of the second edition (Leipzig 1678) in: J. Thomasius, Gesammelte Schriften, Vol. III, edited by Walter Sparn, Hildesheim: Georg Olms, 2003.
3. ———. 1670. Erotemata Logica Pro Incipientibus. Accessit Pro Adultis Processus Disputandi. Leipzig.
   Reprint of the second edition (Leipzig 1678) in: J. Thomasius, Gesammelte Schriften, Vol. II, edited by Walter Sparn, Hildesheim: Georg Olms, 2003.

1. Mercer, Christia. 2004. "Leibniz and His Master: The Correspondence with Jakob Thomasius." In Leibniz and His Correspondents, edited by Lodge, Paul, 10-46. Cambridge: Cambridge University Press.
2. Micheli, Giuseppe. 1993. "The 'Historia Philosophica' in German Scholastic Thought." In Models of the History of Philosophy. Volume I: From Its Origins in the Renaissance to the 'Historia Philosophica', edited by Santinello, Giovanni, 371-473. New York: Springer.
   On Jakob Thomasius see pp. 409-442 by Giovanni Santinello.
3. Santinello, Giovanni. 1978. "Jakob Thomasius E Il Medioevo." Medioevo.Rivista di Storia della Filosofia Medievale no. 4:173-216.

1. Du Hamel, Jean-Baptiste. 1678. Philosophia Vetus Et Nova. Paris.
   Reprint of the 1682 edition: Hildesheim: Georg Olms, 2006.
   Tomus prior, qui Logicam, Metaphysicam et Philosophiam moralem complectitur.
   Tomus posterior, qui Physicam generalem et specialem tripartitam complectitur.

1. Wells, Norman J. 1999. "Jean Du Hamel, the Cartesians and Arnauld on Idea." Modern Schoolman no. 76:245-271.

1. Le Clerc, Jean. 1692. Logica: Sive, Ars Ratiocinandi. [and] Ontologia; Sive De Ente in Genere. [And:] Pneumatologia Seu De Spiritibus. London.
   Reprint in: Opera philosophica in quatuor volumina digesta, Vol. I: Logica & Ontologia, Amsterdam, 1704.

1. Pitassi, Maria Cristina. 1987. Entre Croire Et Savoir: Le Problème De La Méthode Critique Chez Jean Le Clerc. Leiden: Brill.
2. Schuurman, Paul. 2003. "The Empiricist Logic of Ideas of Jean Le Clerc." In The Early Enlightenment in the Dutch Republic, 1650-1750, edited by Bunge, Wiep van, 137-153. Leiden: Brill.
   Selected papers of a Conference held at the Herzog August Bibliothek, Wolfenbüttel 22-23 march 2001.
3. ———. 2003. Ideas, Mental Faculties and Method. The Logic of Ideas of Descartes and Locke and Its Reception in the Dutch Republic, 1630-1750. Leiden: Brill.
   See the chapter V: Jean le Clerc: Lockean empiricism in textbook format (1692), pp. 70-88.

1. Budde, Johann Franz. 1703. Elementa Philosophiae Instrumentalis, Seu Institutionum Philosophiae Eclecticae. Tomus Primus. Halle.
   Reprint in: Gesammelte Schriften - Vol. I - Hildesheim, Georg Olms, 2006.
2. ———. 1703. Elementa Philosophiae Theoreticae Seu Institutionum Philosophiae Eclecticae. Tomus Secundus. Halle.
   Reprint in: Gesammelte Schriften - Vol. II - Hildesheim, Georg Olms, 2003.
3. ———. 1727. Isagoge Historico-Theologica Ad Theologiam Universam Singulasque Eius Partes. Leipzig.
   Reprint in the VIII volume of his Gesammelte Schriften, edited and with a preface by Leonhard Hell, Hildesheim: Georg Olms, 1999.

1. Fabbianelli, Faustino. 2003. Leibniz, Budde Et Wolff. Trois Modèles De Théodicée in Revue Philosophique de la France et de l'Étranger no. 128:293-396.
   The paper deals with the limitations of creatures, namely, more precisely the relationship between man and God amid a universe wanted by the latter. It studies the several attempts by Leibniz, Budde and then Wolff to reconcile human freedom and divine nature. Several axes of analysis are to be set in order to wander along the several patterns of those three authors, i.e. the one which traditionally opposed voluntarism to rationalism and should be contrasted as well as the one which opposes anthropology and theology.
2. Masi, Serenella. 1977. Eclettismo E Storia Della Filosofia in Johann Franz Budde in Memorie della Accademia delle Scienze di Torino:164-212.
   Classe di scienze morali, storiche e filologiche. Serie V. Vol. I.
3. Sparn, Walter. 2006. Einleitung in Elementa Philosophiae Instrumentalis, Seu Institutionum Philosophiae Eclecticae. Tomus Primus, I-LXII. Hildesheim: Gorg Olms.
   Johann Franz Budde, Gesammelte Schriften, Vol. I, Hildesheim: Georg Olms, 2006.
4. Wundt, Max. 1945. Die Deutsche Schulphilosophie Im Zeitalter Der Aufklärung. Tübingen: Mohr.
   On Budde see pp. 63-75.

Christian Wolff's Ontology: Existence as "Complement of Possibility"

INTRODUCTION: BEING AND EXISTENCE

Let us open Wolff's Ontology and read his Preface: "Prime Philosophy (namely, metaphysics) was first laden by the Scholastics with enviable praise, but, ever after the success of Cartesian philosophy, it fell into disrepute and has become a laughing stock to all." (10) What Wolff clearly sees then is that, since the time when Descartes "grew weary of metaphysics," there still may have been metaphysicians, but there has been no metaphysics. As a distinct science, metaphysics has simply ceased to be. And Kant himself was only echoing Wolff when he wrote in his Preface to the first edition of the Critique of Pure Reason: There was a time when metaphysics used to be called the queen of sciences ... Now, in our own century, it is quite fashionable to show contempt for it." Our own century here is the eighteenth century, which was the century of both Wolff and Kant.

When he made up his mind to put a stop to that technical decadence in the field of philosophy, Wolff was keenly conscious of carrying on the work of the great Scholastics. What they had done was not perfect, but that was the thing to do, and, since it could be done better, Wolff himself was going to do it all over again. Let us be as precise as possible. Wolff did not wish to be reproached with bringing back a Scholastic philosophy that was dead. In point of fact, that was not what he wanted to do. But he was claiming the right to retain at least Scholastic terminology, for all there was to be done about it was, keeping the same terms, to build up better definitions and more exactly determined propositions. (11)

This is what Wolff set about doing first with the term Being, and it is typical of his attitude that he can reach it only through the notion of possibility. "Being," Wolff says, "is what can exist and, consequently, that with which existence is not incompatible: Ens dicitur quod existere potest, consequenter cui existentia non repugnat. (12) In other words, what is possible is a being: Quod possible est, ens est. (13) Besides, Wolff adds, this is a metaphysical notion which is accepted by all, and which exactly tallies with common language. Being, "something", "possible;" here are so many words that are practically synonymous, and metaphysics does nothing more than bring their implicit meanings out in the open. True enough, what is commonly called "a being" is something that exists, but he who understands that a A is being because it exists will as easily understand that, if A exists, it is because it can exist.(14) Possibility then is the very root of existence, and this is why the possibles are commonly called beings. The proof of it is that we commonly speak of beings past or future, that is, of beings that no longer exist or that do not yet exist. In any case, their Being has nothing to do with actual existence; it is, though a merely possible being, yet a being.

In order to probe more deeply into the knowledge of Being, what we have to do is to inquire into the causes of its possibility. The first one is, of course, the one we have already mentioned, namely, the absence of inner contradiction; but this is not enough. In order to posit a being, one must ascribe to its notion such constituent parts as are not only compatible among themselves, but are its primary constituent parts. The primary constituents of a being are those which are neither determined by some element foreign to that being, nor determined by any one of the other constituent elements of the same being. If an element supposedly foreign to some being were determining with respect to any one of those elements which enter its constitution, then it would not be foreign to it; it would be one of its constituent elements. On the other hand, if some of the constituent elements of a being determine each other, then we must retain only the determining elements as constituent parts of that being.(15) In short, every being is made up of such elements as are both compatible and prime. Such elements shall be called the "essentials" of Being (em>essentialia), because they constitute the very essence. Hence this conclusion, whose full significance it is superfluous to stress: Essence is what is conceived of Being in the first place and, without it, being cannot be.(16) Thus, the essence of the equilateral triangle is made up of the number three and of the equality of its sides; again, the essence of virtue is made up of a habit (habitus) of the will and of the conformity with natural law of the acts which follow from that habit. Let any one of those conditions be altered, there is left neither equilateral triangle nor virtue; let them be all posited, then there is equilateral triangle and virtue. The presence of the "essentials" of the thing is therefore both necessary and sufficient to define its essence. Those "essentials" always entail certain properties which are inseparable from them and, since a thing never is without its "essentials," it is also inseparable from the thing. Such properties are called the "attributes" of Being. As to its "modes," they are such ulterior determinations which are neither determined by the essence nor contradictory with it. The attributes of a being are always given with it, but not its modes, which are what the Scholastics used to call "accidents".

In a being so conceived, the "essentials" obviously are the very core of reality. Taken as non-contradictory, they ensure the possibility of Being. It is through its "essentials" that a being is Per essentialia ens possibile est. Now, since the essence of Being is one with its possibility, he who acknowledges the intrinsic possibility of a thing knows also its essence. We are saying "acknowledges," and rightly so, for it is possible to account for the attributes of Being from the "essentials" of that being, but there is no accounting for the fact that those "essentials" belong to it. Since they are prime, there is nothing above them from which they could be deduced. As to the modes, they cannot be deduced from their essence either. For, what makes up an essence accounts for the fact that such and such a mode may belong to a certain being; it does not account for the fact that such a mode actually does belong to it. The reason for the actual presence of modes in a given being must always be looked for outside that being. We call "external" those beings which constitute the sufficient reason for the actual presence, in a given being, of modes which cannot be sufficiently accounted for by its essence alone. The essence then is for any being the sufficient reason for the actual presence of its attributes and of the possible presence of its modes(17) Hence its nominal definition: "Essence is that which is conceived of a being in the first place, and in which is to be found the sufficient reason why all the rest either actually belongs to it or else may belong to it: Essentia definiri potest per id quod primum de ente concipitur et in quo ratio continetur sufficiens, cur caetera vel actu insint, vel finesse possint." (18)

The scrupulously exacting method which Wolff was using in his determination of Being was entirely his own, but the results achieved by that method had really nothing new. And Wolff himself was clearly aware of it.

In Christian Wolff we have a Leibniz purged of poetry, but also purged of some exaggerated conceptions, for example, the drowsy or slumbering monads, and the phenomenal character of space. All is built into an immense, systematic exposition, magnificent in its formal rigour and clarity, and building on, though also improving, the ontological, cosmological, and theological doctrines of the Aristotelian schoolmen and, in particular, of Suárez. (The improvements are possibly due to Platonizing influences, which modified the ingrained love of the individual instance so characteristic of the Aristotelians.) Christian Wolff expounded his systematization both in a German version (the Logic, Metaphysics, Ethics, Politics, Natural Theology, etc.), and also in a Latin version (a Logic (1728), an Ontology (1730), a Cosmology (1731), a Psychology (1732 and 1734), a Natural Theology (1736-7), and a Universal Practical Philosophy (1738-9)). There are also many political writings of interest. To this vast system, with its innumerable Epigonoi -- Bilfinger, Meier, Rüdiger, Baumgarten, Tetens, Crusius, and so on -- Kant made his great emendations, which have been exaggerated into the idealisms, and later the positivisms, by which the thought and even the public policy of Europe has been bemused. What is, however, amazing is the immense volume and solid merit of Wolff's works, and the almost total misunderstanding and neglect that has since enshrouded them, so that copies of Wolffian books are hardly to be found in libraries outside of Germany.

Wolff's Ontology begins (27) with the assertion of the two laws of contradiction and sufficient reason, both fundamental to the assertion that something is, or that it is not. The former requires that what is must be free from inner conflict, the latter that, if it does not, like a necessary being, have a reason for being in its own nature, it must depend on such a reason in something other than itself. The law of causation, as we ordinarily understand it, is for Wolff only a special form of the law of sufficient reason, pertinent to temporal, changeable things and their states (71). From these principles Wolff proceeds to the consideration of the metaphysical modalities, of which the most fundamental is the possible, the negation of the self-contradictory, or logically impossible. Everything actual, he holds, is by the law of contradiction possible, but he here embraces some invalid theorems, for instance, that a possible consequence can only have possible premisses. Obviously, modal logic is still insecure, though Wolff's treatment of apagogic proof in 98 is of some interest. From Wolffian principles it follows that the notion of an entity not wholly determinate is 'imaginary', and that the indeterminate is only what is for us determinable, and that it will have to be determined by a sufficient reason (111, 117). There is no room in Wolffianism, any more than in Leibnizianism, for radical alternativity: Kant, however, will diverge from this position under the influence of Crusius.

All this leads, however, to Wolff's treatment of what he calls an entity: an entity is defined as any thing which can exist, to which existence is not repugnant. Thus warmth in this stone is a something, an entity, since a stone certainly can be warm or a warm stone can exist. There does not need to be any actual stone-warmth for us to have an entity before us. An entity is, however, rightly called fictitious or imaginary, if it lacks existence, which does not, however, make it less of an entity. These near-Meinongian positions are of great contemporary interest, and form the spring-board for much of Kant's later criticisms of the ontological proof, which is Wolffian enough to treat 100 possible dollars as if they certainly vere something. Wolff goes on to draw the distinctions of essential features and attributes, on the one hand, which always must belong to an entity, and its modes, on the other hand, which are merely the characters that it can have and also can not have. Obviously, however, something must be added to possibility to raise it to full existence, and this Wolff is simply content to call the possibility-complement ( 174). It rather resembles the modal moment of Meinong. He proposes to deal with this possibility-complement separately in his discussions of different spheres, for example, theology, cosmology, and psychology, since the intrinsically sufficient reason which makes God an actual existent is not at all like the extrinsically sufficient reason which underlies existence in the cosmological sphere. It is deeply characteristic, and deeply interesting, that Wolff should make actuality a mere enrichment of the possible, not the latter an impoverished abstraction from the former. The efforts of Wittgenstein, Carnap, Ryle, Quine, and so on have shown the hopelessness of trying to elucidate the possible in terms of the actual: the traditional priority may well prove more successful. Both tendencies are of course manifest in Kant's treatments of possibility, the 'modern' in, for example, the Postulates of Empirical Thought, and the Wolffian in many 'transcendental' contexts. Individuation does not, for Wolff, represent a going beyond the possible. It merely occurs where we have the complete determination which the logico-ontological laws require, and there are, accordingly, imaginary and fictitious as well as real ones. The latter may be far more determinate than any characters in fiction, but they will still lack a final nuance of determination. There are, likewise, incompletely determinate specific and generic properties of individuals, all of which must rank among imaginary entities, though some, connected with actual instances, will obviously be less imaginary than others. Wolff has here developed points which Meinong was later to develop in his doctrine of complete and incomplete objects, and there are also many anticipations of the modern theory of possible worlds.

One cannot plunge directly into Wolffian natural theology, however, since it must be viewed within the closely knit context of a certain conception of philosophy and ontology. From Wolff's opening definition of philosophy as 'the science of possibles, in so far as they can be' or have an essential nature, it is evident that his is a system of possibility and essence in which the role of existence is a subordinate one. It is not a totally de-existentialized philosophy; it is one in which knowable and systematically exploitable being primarily means the possible essence and in which existence is admitted only by virtue of some correlation it has with this essence. What does not stand out so clearly is the reason why Wolff settled upon this essentialist viewpoint and yet never totally submerged the distinctive reality of existence.

Part of the explanation comes from Wolff's complex intellectual heritage. He was just as thoroughly familiar with the critical work of the skeptics and empiricists as with the rationalist tradition. The skeptical arguments convinced him of the impossibility of demonstratively defending our knowledge of the existing external world, either through a rationalist deduction or through an empiricist inference. Hence he concluded that it was too risky to base his philosophy upon the thesis of the reality of the material universe; his fundamental definitions remained deliberately neutral about the independent existence of a world corresponding with our ideas. This skeptically generated neutrality inclined him to focus upon the essential and the possible, without making any primary commitments about sensible existents. Nevertheless, the British scientists and philosophers also convinced him of the danger of entirely ignoring the existential aspect.

As a compromise, Wolff calls for a union in holy matrimony of three kinds of human knowledge: historical, philosophical, and mathematical. Historical knowledge means the empirical assurance, gained mainly through sense experience and experiments, that certain things exist or occur. Wolff hails it as the foundation of all philosophy and the constant guide of all inferential reasoning. Yet he wavers between saying that empirical knowledge assures us indubitably that certain things actually do exist and saying that it merely makes us reflectively aware of having the ideas of things that can exist or come to be. This ambiguity about the import of sense experience stems from his basic epistemological neutrality and leads him to depreciate its certainty. Experiential certainty concerns the bare fact (real or ideal) and does not extend to the sufficient reason for the fact. Hence philosophical certainty must be non-experiential in its own proper form. Every ounce of it (to use Wolff's own emphatic phrase) derives from the use of the mathematical method, which risks nothing on the real existent but concentrates upon the determinate quantity of possible objects and essential relations. This method enables philosophy to determine with perfect certainty the reasons why objects may come to be or why Being is possible. Hence philosophy is primarily a study of the internal essentialia, or essential components, and the external reasons, or causes of the possibility of these essential components. Existence is studied properly in philosophy only to the extent that it can be drawn out with certainty from the known essential structure.

Wolff never removes the radical dichotomy between empirical and mathematico-philosophical certainties, between knowledge of fact and of possible essence. Their matrimonial bond is not based upon some unifying doctrinal principle but rests solely upon Wolff's personal awareness of the need for both approaches. His desire to found philosophy on an existential basis in experience is blocked by the skeptical critique, and he is thereby forced to locate philosophical certainty in the possible essences and their sufficient reasons. And yet he is also unwilling to follow 'Leibniz in overcoming the distinction between truth's of fact and truths of essence by means of the principle of sufficient reason. Leibniz accords the primacy to this principle, since it expresses the dynamic law of quasi-autonomous essences, to which God must give a consent decree governing His creation of the existing world. For Wolff, however,,the essences are unequivocally grounded in the divine intellect and enjoy no quasi-independence. Hence the principle of sufficient reason can give essential connections or reasons for facts, but it cannot furnish any deductive certitude concerning the actual facts themselves or existential productions of the divine will, There is no objectively determining ground which shapes God's existential decisions and closes the gap in man's philosophical system. Hence the principle of sufficient reason must remain subordinate to the principle of contradiction, which provides an indubitable certainty, at least, about the internal consistency and possibility of the essential traits as such.

In conformity with this view of philosophy, Wolff then defines ontology as the science of Being, i.e., of that which can exist or that to which existence is not repugnant. In the main, it is the science of essence, namely, "that which is first of all conceived about Being, and in which is contained the sufficient reason why other aspects either actually belong to it or can belong to it." Ontology is a strict science precisely because it confines itself to a general study of Being as possible or essentially constituted -- the sphere where a mathematically rigorous certitude is obtainable. Existence figures in ontology either obliquely, as the complement of possibility, or negatively, as the furnisher of a norm of non-repugnance. As the directly known act of a thing, it does not come within the scope of ontology, which remains a nonexistential discipline. Because of the nonexistential character of ontology or general metaphysics, Wolff requires three special parts of metaphysics to determine the principles of the possibility of existence in the three main areas of Being. Cosmology studies the reasons of being in the contingent, material world; psychology deduces the soul as the sufficient reason for the existence of mental acts; natural theology demonstrates God as the ground of existence for His own attributes and modes, as well as for the existence of the world. Natural theology presupposes these other sciences. From ontology, it draws its general principles and orientation; from cosmology, a factual basis in the material world; from psychology, a basis in the soul and also some special insight into the spiritual perfections which help us to know God's nature.

AN OVERVIEW OF CHRISTIAN WOLFF'S PHILOSOPHIA PRIMA SIVE ONTOLOGIA

Wolff's Ontology is a long, systematic treatise of what had been generally called before him "metaphysics" or "first philosophy." The term 'ontology' to refer to this rather traditional discipline had antecedents before Wolff used it in the title of his book, however. In 1647 Clauvergius [Johannes Clauberg] published a treatise with the title Elementa philosophiae sive ontosophia in which he explicitly argued in favor of a more precise name for what was generally called "metaphysics." The primary reason behind the shift of terminology had to do with the object of study of the discipline, which Clauvergius identified with Being in general.(10) Wolff, following suit, titled his book Philosophia prima sive ontologia (1729), defining the subject of study as the science of Being in general, that is, of being insofar as it is being.(11)

The Ontology, in comparison with the extensive systematic metaphysical treatises of late Scholastics, is fairly short. It is divided into three sections: a section entitled "Prolegomena" and two parts. The Prolegomena deals with the nature of ontology and of the terms and notions with which it concerns itself. In the first of the two parts into which the rest of the treatise is divided, Wolff discusses the notion of Being in general and the properties that follow from it. In the second part, he is concerned with the various species of Being. The first part is divided in turn into three subsections, dealing respectively with the principles of ontology, the essence and existence of Being, and the general attributes of Being. After Wolff discusses identity and similarity in Chapter 1, he then deals with singular and universal Being in Chapter 2. Thus, the discussion of singularity, which for Wolff is equivalent to individuality, precedes the discussion of necessity, contingency, quantity, quality, relation, truth, perfections, and related notions.(12) It is also worthy of note that in the chapter devoted to individuality and universality, individuality is listed and discussed first.

The relative position that individuality occupies in relation to other fundamental metaphysical notions, including universality, indicates the importance that Wolff attached to it as well as its more fundamental and central role in the Ontology. Not that such importance and central role were something new. Throughout the Middle Ages there had been a progressive shift of emphasis from universality to individuality, which is clearly evident as early as the thirteenth century when Duns Scotus discussed universals in the context of individuals in the Opus oxoniense, contrary to what had been customary before him. This shift is most evident in Suárez's Disputationes metaphysicae, where individuality is given separate, prior, and more extensive treatment than all the other common properties of Being.

What is most significant and different structurally speaking about Wolff's Ontology, vis-à-vis the later Scholastic tradition, is something else, namely, the epistemic and methodological considerations that are contained in the beginning of the work. They are found in two places. In the Preface Wolff presents some general statements about his modus operandi, indicating among other things that his aim is to make clear notions that are only confusedly found in common as well as in previous philosophical discourse, and also pointing out that he intends to follow the rigorous mathematical method popular among other modern philosophers. In Section 1, he begins the discussion with an examination of the methodological principles that guide his investigation. The principles in question are the "principle of contradiction" and the "principle of sufficient reason." The methodological concerns expressed both in the Preface and in Section 1 are certainly an indication of the epistemic bent that Wolff gave to the Ontology and that do not seem to have affected the work of many late Scholastics. Suárez's Disputationes, for example, go directly from a discussion on the nature of metaphysics to the discussion of the common properties of Being and do not contain in the Preface the kind of procedural comments that characterize the Ontology. What distinguishes Wolff's Ontology, then, is that between the discussion of the nature of metaphysics and of the common properties of Being he adds a section on methodological principles and that he prefaces the whole work with a series of remarks on the same topic.

Thus, although the Ontology aims to be a work of metaphysics, from its very beginning we are confronted with epistemic and methodological considerations. Does this mean that its contents suffered from the epistemologism that characterize most other modern metaphysical works? I argue yes at least as far as individuation is concerned.

THE PRELIMINARY DISCOURSE ON THE PHILOSOPHY IN GENERAL (1728)

The Preliminary Discourse on Philosophy in General presents Wolff's master plan for the synthesis of knowledge. Written in 1728, it was intended to serve as the general introduction to his Latin survey of the branches of systematic philosophy, with subsequent volumes on logic, cosmology, empirical psychology, rational psychology, ontology, natural theology, and moral philosophy. Though in writing the Preliminary Discourse Wolff used many notions he intended to develop more fully in these later volumes, the book nevertheless is a basically self-contained discussion; in fact, this work contains Wolff's clearest presentation of his theory of the division and method of the sciences, and its main historical interest lies along these lines.

The overall outline of Wolff's theory is presented in Chapter One of the Preliminary Discourse. He defines history as knowledge of the facts pertaining to both the material world and the world of consciousness, and as such, history provides the empirical foundation of the sciences. But as Aristotle had pointed out centuries earlier, knowledge of the facts is one thing and knowledge of the reason of the facts is quite another thing. This latter constitutes the proper province of philosophy. His third major division of natural knowledge, namely, mathematics, which deals with our knowledge of the quantity of things, employs a method of extraordinary power which is applicable to philosophy; insofar as philosophy shares in the values of mathematical method, it attains to complete certitude. Thus Wolff recognizes the importance of both the empirical methods of historical knowledge and the rational methods of the mathematical sciences. And for him, philosophy is the common meeting ground of these two methods.

The definition of philosophy presented in Chapter Two is of considerable interest. As the science of the possibles insofar as they can be, philosophy must concern itself both with the intelligibility of the world of the possibles and also with the reasons why certain of these possibles become actual. The former is governed by the Principle of Contradiction while the latter is controlled by the Principle of Sufficient Reason. What this means in brief is that for something to be possible it must be internally consistent. The criterion for determining this mutual consistency and intelligibility of the component elements of a possible is the Principle of Contradiction. However, this principle alone does not explain the fact that some possibles are actual while others are not; the mere internal consistency of a possible does not confer actuality upon it. A full understanding of the actual must go beyond the Principle of Contradiction to include an explanation of why this possible rather than another is actual. This further explanation is what is demanded by the Principle of Sufficient Reason. Furthermore, existence is understood by Wolff to be the final complement in the order of possibility." As a result, all philosophical problems for Wolff deal with the constitution and ordering of possibilities or essences. The two great principles are adequate to govern all of these essentialistic relationships, and the door is thus opened for the casting of the entire philosophical enterprise into the formal, deductive pattern outlined in Chapter Four.

Both the order of demonstration within each individual science and the proper subordination of the various sciences to each other are determined by the demands of one continuous deductive sequence. Wolff explains these relationships in great detail in Chapters Three and Four. The individual parts of philosophy are distinguished exclusively on the basis of subject matter or material object divisions, as is clear from the summary on the following page, and each branch of philosophy is carefully located in its proper place of subordination to the more basic disciplines. Further, according to Wolff, the methods of deductive logic apply universally to all these disciplines.

TWIN PILLARS OF PHILOSOPHY: THE PRINCIPLE OF CONTRADICTION AND SUFFICIENT REASON

Wolff's explicit presentation of the Principle of Sufficient Reason occurs at the beginning of his Ontologia. (44) His approach to this Principle and the Principle of Contradiction is not by way of the notion of Being and a deduction therefrom, although a cursory glance at the arrangement of his text might lead one to think so, especially after familiarity with later manuals which follow this development. Rather, Wolff makes these "twin pillars of philosophy” more intuitional than deductive; they are the given of the rationalistic mind generating its own data and starting points.(45)

Systematically, the Principle of Sufficient Reason is preceded by the Principle of Contradiction, and Wolff places the foundation of this latter in an obvious experience of mental life: While we are judging something to be, it is impossible at the same time to judge it not to be(46) From this conscious experience of the nature of our minds, we concede without need of proof the proposition enunciated in general terms as the Principle of Contradiction: It cannot happen that one and the same thing be and at the same time not be. Or, another form of the same: If A is B, it is false that the same A is not B.(47)

To demonstrate the fecundity of this basic axiom, Wolff explores its logical implications and leaves little doubt that the principle for him is a purely formal one, a kind of aliquid to which subsequent concepts in his system may be tied. If it were not a true principle, he argues, then the same predicate could and could not pertain to the same subject under the same determinations, and the same proposition could be both false and true at the same time.(48) Besides "contradiction is simultaneity in affirming and denying,"(49) it is contained in two propositions, of which "one takes away what the other posits.

The important point is that the process of building concepts and working out demonstrations is insured by this principle against logical failure. Negatively, it is important to note that while this treatment is placed under ontology and the subject of Being in general, yet with no systematic reference to or involvement of existential judgment or sensation, it is not possible to denote this principle as anything more than logical.

Proceeding next to the Principle of Sufficient Reason, Wolff does not make any detailed reference to the question of its relation to the Principle of Contradiction. To anyone following through within the system itself, the question of whether it reduces to the Principle of Contradiction is answered by the fact that the latter is the one systematically prior, and this priority makes reduction possible.(50)

Clearly, the dual sovereignty granted these principles by Leibniz no longer holds. Leibniz had located the relation between the Principle of Contradiction and the Principle of Sufficient Reason in the realm of the rational through his distinction between necessary and contingent truths. Wolff unified that realm of the rational around the Principle of Contradiction.(51) Again we can note the lack of existential reference in the fact that this realm remained distinct from that of the singular concrete sensible data of experience. Under the influence of Locke and the rise of empirical science, Wolff and his successors heightened the reality of this latter realm and deepened the realization and the value of its experience. But the systematic failure to incorporate it into an existential union with the realm of the rational will continue to haunt modern philosophy.

Unity in the order of essence, however, is impressively systematic. The possible as the non-contradictory, we shall see, gives to the Principle of Contradiction a primacy which it can share with no other. The ratio or reason whereby things are understood is ultimately explicable in terms of the opposition between "nothing" and "something," the latter being the systematic coherence of clear and distinct ideas whose right to, and precise determination of, a place in the system ultimately depends on the Principle of Contradiction. The Non-Contradictory is "something".(52)

This application of the primacy of essence to a theory of method grants priority to the Principle of Contradiction over the Principle of Sufficient Reason, and to the Principle of Sufficient Reason over causality. In other words, when Wolff has defined philosophy in terms of possibles rather than causes, he must use ratio instead of causa to describe the object of the metaphysical search, and it is one of the inevitabilities of such a system that "reasons grow more rational and logical; causes, more empirical and real."(53) The deductive method of mathematics becomes the unique method of philosophy, and here-and-now existential reference is obtained by "common sense" joined sometimes with a pious use of Sacred Scripture.

By Sufficient Reason, Wolff meant whatever explains why something is; it is "that whence it is understood why anything is."(54) He gives two examples: The three sides of the triangle, or rather, its three-sidedness is sufficient reason for the three angles because this suffices for us to understand the triangle as having three angles.(55) In the order of motivation and action he further instances the case of a man rising to his feet out of respect for some person who has just entered the room. From the fact of this entry, plus the reverence due the newcomer, it can be understood why the man in the room rises to his feet and hence a sufficient reason for the action is assigned.

In keeping with his methodology of building notions and demonstrations from previously established concepts, it is now necessary to define the meaning of "nothing" and "something" as involved in the notion of "sufficient reason." This is very simply managed in terms of the basic building block itself, the notion or concept. We call that "nothing" to which no notion corresponds. And "something" is that to which some notion can be attributed or corresponds. (56) pp. 35-38

EXISTENCE IS A MODE OF FINITE BEINGS

Because the Being of Wolff's metaphysics is possible being, existence is not one of its essential determinants. In fact, Wolff defines existence as "The complement of possibility. And existence is also called Actuality." (44) Because existence is neither an essential of Being nor an attribute inseparable from it, existence must be regarded as a mode. Hence it will depend upon a cause outside the being which possesses it. Therefore, as Gilson observes, in the philosophy of Christian Wolff, "the sufficient reason for the actual existence of any finite being is never to be found in that being itself; it always is to be found in another one." (45)

All this is necessary for a proper understanding of Wolff's definition of substance as a subject which is modifiable and perdurable. Because substance in Wolff's ontology is a possible being, it can be readily seen why Wolff calls it a subject which is modifiable rather than modified. The Being of Wolff's metaphysics is possible being, not actual or existent being. Modes are characteristics or determinations of existent Being, consequently while a substance is conceived as capable of having modes (capax aliorum), these accidental determinations are never actually possessed by it in its ontological or possible existence.

Baumgarten's basic argument for the existence of a special faculty of sensitive cognition leads back to the core of his metaphysics. To be aware of the material perfection of the world from a finite point of view is, he held, possible only in a sensitive way that is not overwhelmed by abstractive concepts of the intellect. For Baumgarten, beauty is the observable phenomenon representing this material perfection, and the finite created mind is able to gain consciousness of it because of its original disposition to represent the reality and order of the world by clear but confused perceptions. Baumgarten elaborates a set of conditions for the 'art of thinking beautifully' (ars pulchre cogitandi ). He hereby relies on the doctrines of 'special metaphysics': cosmology, psychology, and the discipline yielding the ultimate ground of the relation between these, namely natural theology.

In his account of metaphysics Baumgarten in general follows Wolff. The first main part is 'ontology' or 'general metaphysics'. This sets out the 'predicates of Being'. Baumgarten interprets the principle of contradiction in a way which yields the basic ontological concept 'something' or simply 'thing' (ens): what is not 'A and not-A', i.e. 'nothing' (nihil ), is 'something' (non-nihil). The universal connection of all things is governed by the principle of ratio and rationatum: whatsoever B exist, is founded in something other A, and at the same time there is something other C which is founded in B. The further universal predicates are unum, ordo, verum, and perfectum, traditionally called the 'transcendental' predicates of Being.

Baumgarten's ontology manifests much sophistication. Yet there are profound difficulties which cannot be ignored. How, for example, can the universal predicates be compatible with each member of such disjunctive predicates as: necessary/contingent; changeable/unchangeable; real/unreal; singular/universal; total/partial; finite/infinite; simple/composed; substance/accidence? The universal and disjunctive predicates constitute the internal determination of the ens qua ens. They differ altogether from such external (or 'relative') predicates as: similar and diverse, simultaneous, successive, cause and caused, etc. The ontological predicates then furnish the basic material for most of the arguments of special metaphysics. In two points Baumgarten proves especially his independence from Wolff: in his doctrine of monads as immaterial, inextended substances; and in his doctrine of pre-established harmony in the absence of influxus physicus.

He herewith reinstitutes the genuine ideas of Leibniz, more than any other of the Wolffians.

1. Baumgarten, Alexander Gottlieb. 1739. Metaphysica. Halle.
   Reprint of the Seventh edition (1779): Hildesheim, Georg Olms, 1969.
   English translation by Courtney D. Fugate and John Hymers: Metaphysics. A Critical Translation with Kant's Elucidations, Selected Notes, and Related Materials, New York: Bloomsbury Academic, 2013.
2. ———. 1770. Philosophia Generalis. Edidit Cum Dissertatione Prooemiali De Dubitatione Et Certitudine Johann Christian Foerster Halle.
   Reprint: Hildesheim, Georg Olms, 1968.
3. ———. 1998. Die Vorreden Zur Metaphysik. Frankfurt: Klostermann.
   Introduction to the First (1739), Second (1742) and Third (1749) editions of the Metaphysica edited, translated in German and annotated by Ursula Niggli.

1. Casula, Mario. 1973, La Metafisica Di A. G. Baumgarten Milano: Mursia.
2. ———. 1979. A. G. Baumgarten Entre G. W. Leibniz Et Chr. Wolff in Archives de Philosophie no. 42:547-574.
   Historically Wolff recedes from Leibniz while Baumgarten, coming nearer to Leibniz, recedes from Wolff. If they are compared on two major issues: monadology and pre-established harmony, together with the principle of sufficient reason, concept of substance as force, concept of individual substance, it appears (as in our work on Baumgarten's metaphysics) that Baumgarten is more Leibnizian than Wolff. His metaphysics is the first Leibnizian-Wolffian philosophy; he assumes and develops, with the methodology of Wolff, the philosophy of Leibniz.
3. Pimpinella, Pietro. 2001. Cognitio Intuitiva in Wolff E Baumgarten in Vernunfkritik Und Aufklärung. Studien Zur Philosophie Kants Und Seines Jahrunderts. Norbert Hinske Zum Siebzigsten Geburstag, edited by Oberhausen, Michael, Delfosse, Heinrich and Pozzo, Riccardo, 265-294. Stuttgart: Frommann-Holzboog.
4. Tonelli, Giorgio. 1975. Casula on Baumgarten's Metaphysics in Kantstudien no. 66:242-243.
   Review of Mario Casula (1973).

Crusius, in his Entwurf der Nothwendigen Vernunftwahrheiten (Sketch of Necessary Rational Truths; Leipzig, 1745), divided metaphysics into ontology, theology, cosmology, and pneumatology, in explicit opposition to Wolff's ordering of the metaphysical sciences.

Ontology begins, not with first principles, but with the notion of a thing in general, directly connected with the notion of a "really given thing'. Only after introducing these notions did Crusius discuss essence, existence, and causality. Crusius regarded existence as indefinable and as a primary notion arising from sensation.

In his discussion of causality, Crusius expounded a principle of determining reason, his version of Gottfried Wilhelm Leibniz's principle of sufficient reason. Crusius held, against Wolff, that a sufficient reason suffices only for free actions insofar as they are free. Rational truths and natural events not depending on free causes need a more cogent foundation, a determining reason. This principle does not derive from the principle of identity, but rather from what we must conceive or what we cannot conceive as united or separate, and thus from a new case of the principle of cogitabilitas. Crusius, aiming at a sharper distinction between mechanism and free actions, held that the real nature of causality is unknown and that our knowledge of causal connections is based on the constant conjunction of two events in experience. This, of course, cleared the path for the members of his school to accept the Humean critique of the causal connection.

Crusius's ontology reveals a general characteristic of his metaphysics. His was not a monolithic system beginning with a single principle and deducing from it all subsequent notions and propositions, as was Wolff's. Rather, it was founded both on several independent principles and on a multitude of elementary notions that could be defined only by an appeal to reality (by their concrete representation)--notions such as existence, space, time, and force; or, in psychology, the particular powers of the soul, some mental faculties, and pleasure and pain. Through Hoffman Crusius derived this view from Locke's doctrine of simple ideas, but he supposed that the number of elementary notions (which he once called categories) could be infinite.

1. Crusius, Christian August. 1964. Die Philosophische Hauptwerke. Hildesheim: Georg Olms.
   The main philosophical works, edited by Giorgio Tonelli in 4 volumes.
2. ———. 1964. Entwurf Der Nothwendigen Vernunft-Wahrheiten, Wiefern Sie Den Zufällligen Entgegen Gesetzt Werden. Hildesheim: Georg Olms.
   Vol. 2: Sketch of the necessary truths of reason, insofar as they are opposed to contingent truths. Reprint of the edition published at Leipzig in 1775, (948 pages) [The metaphysical work].
3. ———. 1965. Weg Zur Gewissheit Und Zuverlässigkeit Der Menschlichen Erkenntnis. Hildesheim: Georg Olms.
   Vol. 3: The Way to the Certainty and Dependability of Human Knowledge. Reprint of the edition published at Leipzig in 1747, (1132 pages) [The logical work].
4. ———. 1969. Anweisung Vernunftig Zu Leben: Darinnen Nach Erklarung Der Natur Des Menschlichen Willens Die Naturlichen Pflichten Und Allgemeinen Klugsheitslehren Im Richtigen Zusammenhange Vorgetragen Werden. Hildesheim: Goerg Olms.
   Vol. 1: Guide to rational living. Reprint of the edition published at Leipzig in 1744, with an introduction by Giorgio Tonelli (LXIV, 886 pages) [The ethical work].
5. ———. 1987. Kleinere Philosophische Schriften. Hildesheim: Georg Olms.
   Vol. 4.1: Minor philosophical writings. Reprint of the edition published at Leipzig in 1749, (Edited by Sonia Carboncini and Reinhard Finster, with an introduction by Sonia Carboncini, XXXVI, 695 pages).

1. Beck, Lewis White. 1969. Early German Philosophy. Kant and His Predecessors. Cambridge: Belknap Press.
   Chapter XVI: On the Threshold of the Critical Philosophy. Crusius pp. 394-402.
2. Carboncini, Sonia. 1986. Christian August Crusius Und Die Leibniz-Wolffsche Philosophie in Beiträge Zur Wirkungs- Und Rezeptionsgeschichte Von Gottfried Wilhelm Leibniz, edited by Heinekamp, Albert, 110-125. Stuttgart: Franz Steiner.
   Studia Leibnitiana vol. 26.
3. Fabbianelli, Faustino. 2004. Christian August Crusius: I Presupposti Metafisici in Rivista di Storia della Filosofia no. 59:737-744.
4. Heimsoeth, Heinz. 1956. "Metaphysik Und Kritik Bei Chr. A. Crusius. Ein Beitrag Zur Ontologischen Vorgeschichte Der Kritik Der Reinen Vernunft Im 18. Jahrhundert." In Studien Zur Philosophie Immanuel Kants. Metaphysische Ursprünge Und Ontologische Grundlagen, 125-188. Köln: Kölner Universitätsverlag.
   Originally published in 1926.
5. Koriako, Darius. 1999. "Crusius Über Unmöglichkeit Einer Letztbegründung Der Logik." Studia Leibnitiana.Zeitschrift für Geschichte der Philosophie und der Wissenschaften no. 31:99-108.
   "In this paper we examine some passages of a logical treatise by Christian August Crusius. It seems that Crusius anticipated what might be called the circle of deduction, first discussed by Lewis Carroll.
   The question now emerges: why was it possible for Crusius to have deeper logical insights than his contemporaries, given that he was not a brilliant logician? The answer here proposed traces these insights back to his very peculiar philosophical premisses, which have been important for Kant's development in his early career."
6. Krieger, Martin. 1993. Geist, Welt Und Gott Bei Christian August Crusius. Erkenntnistheoretisch-Psychologische Perspektiven Im Kontrast Zum Wolffschen System. Würzburg: Königshausen & Neumann.
7. Tonelli, Giorgio. 1967. "Crusius, Christian August." In The Encyclopedia of Philosophy, edited by Paul, Edwards, Vol. 2, 268-271. New York: Macmillan.
   Vol. 2.

A. Simple concepts. Simple, or fundamental, concepts (Grundbegriffe) are a subclass of empirical concepts (Erfahrungsbegriffe) and must be found by the Lockean method of collecting and inspecting (Musterung) examples. But whereas empirical concepts may be erroneous (i.e., may have no object corresponding to them) and give only a mere delusory appearance of things, the fundamental concepts are derived from the experience of the sensu interno and must be granted even by the skeptic (the solipsist, der Egoist) who denies the existence of everything except himself and his experience.(45) The simple concepts can only be ostensively defined, not nominally. They can appear as predicates in a judgment whose subject is a complex empirical concept; but in this case the subject can be analyzed into simple concepts, and the original judgment will thereby be resolved into tautologies ("white is white"), simple negative propositions like Locke's intuited disagreements of ideas ("white is not black"), or relational propositions (such as "space has length, breadth, and height" or "motion has velocity and direction") .(46)

B. Combinations of simple concepts. Our knowledge of such propositions is a priori, for though experience is necessary if we are to have the concepts, we do not have to experience their combinations to see the truth of the propositions.(47) The various sciences are based upon some of the simple concepts (for example, geometry on that of space, chronometry on that of time, phoronomy on space and time, "agathology" on the concept of good), and Lambert builds up large and elaborate tables showing what simple concepts are involved in each of the branches of science and philosophy.(48)

But while Lambert is clear in his theory of simple concepts, his theory of their combination is no more satisfactory than that of Crusius. Lambert uses a weaker form of Crusius' criterion of what can or cannot be thought together, calling it the criterion of "thinkability" (Gedenkbarkeit). But while thinkability is a test for a concept, something stronger is needed as a test for judgment; "not to be thought apart," or "must be thought together" as Crusius would say, are needed. This criterion of thinkability, or inseparability, applies to propositions whose predicate is included in the subject, as Leibniz thought; but obviously it will not work for that reason on propositions connecting simple subjects and predicates. Lambert sometimes appeals to the law of contradiction, which in turn is based upon the incredibility (nicht-glauben-lassen) of contradictions(49) and sometimes to the mere possibility of thinking a combination of ideas under maxim that "cogitabile is equal to possibile."(50) But if Gedenkbarkeit is too weak a test, the law of contradiction is too stringent, and Lambert must rightly confess that the "fons possibilitatis duos ideas combinandi has not been fully discovered."(51) It was to remain hidden until Kant clearly distinguished the synthetic a priori from the analytic; and to explain the kind of combinations Lambert and Crusius were concerned with required the whole labor of the Critique of Pure Reason.

The total system of all the simple concepts and their permissible combinations constitutes what Lambert calls the realm of truth.(52) It is equally the object of logic (i.e., the science of reason, Vernunftlehre) and ontology, which is therefore completely a priori, since it deals with objects only insofar as they are possible. Still, Lambert does not wish the realm of truth to be defined solely in formal terms as a set of non-contradictory propositions having simple concepts as their subjects. He speaks rather of a harmony(53) reigning in the realm of truth. Harmony is what later in the history of philosophy will be called "coherence." Each proposition in the system is not only consistent with all the others, but harmonizes with it in some more intimate fashion, supporting and being supported by all the others. Every erroneous proposition can be discovered by a stepwise process (Schritt für Schritt, as Lambert liked to say) of testing it against each of the others; but since every proposition is ultimately reducible to simple concepts which are always logically true, every error contains some truth which we are to discover by analysis. The most harmonious system is, by definition, the logically true system: wholly unified, with no contingencies, and completely comprehensive. Any lacuna is a warning, and any dissonance a sign of error.(54)

1. Lambert, Johann Heinrich. 1764. Neues Organon. Leipzig.
   Anastatic reprint by H.-W. Arndt in Philosophische Schriften voll. 1-2.
   Italian translation by Raffaele Ciafardone: Nuovo organo, Bari: Laterza 1977.
   English translation of selected passages in: Eric Watkins, Kant's Critique of Pure Reason, Background Source Materials, Cambridge, Cambridge University Press, 2009, pp. 257-274.
   The work is divide in four parts: I. Dianoiology, the laws of thought; II. Alethiology, the doctrine of truth; III. Semiotic, the doctrine of signs; 4. Phenomenology, the doctrine of appearances.
2. ———. 1771. Anlage Zur Architektonik Oder Theorie Des Einfachen Und Ersten in Der Philosophischen Und Mathematischen Erkenntniss. Riga.
   Anastatic reprint by H.-W. Arndt in Philosophische Schriften voll. 3-4.
   Italian translation by Raffaele Ciafardone: Disegno dell'architettonica, o teoria del semplice e del primo nella conoscenza filosofica e nella conoscenza matematica, Napoli: Ortothes, 2012.
3. ———. 1915. Abhandlung Vom Criterium Veritatis (1761) in Kant-Studien no. 36:7-64.
   First postumhous edition by Karl Bopp; partial English translation in: Eric Watkins, Kant's Critique of Pure rason, Background Source Materials, Cambridge, Cambridge University Press, 2009, pp.233-257.
4. ———. 1918. Über Die Methode, Die Metaphysik, Theologie Und Moral Richtiger Zu Beweisen (1762) in Kant-Studien no. 42:1-36.
   First postumhous edition by Karl Bopp.
5. ———. 1965. Philosophische Schriften. Hildesheim: Georg Olms.
   Anastatic reprint of the editions Leipzig, 1764 (v. I-II); Riga, 1771 (v. III-IV); Berlin 1782-87 (v. VI-VII, IX) by Hans-Werner Arndt; v. X: Entwürfe und Rezensionen aus dem Nachlaß (in three tomes, with an Introduction by A. Emmel and A. Spree, edited by Lothar Kreimendahl, 2008.

1. Colloque International Et Interdisciplinaire Jean-Henri Lambert, Mulhouse, 26-30 Septembre 1977. 1979. Paris: Ophrys.
2. Basso, Paola. 1999. Filosofia E Geometria. Lambert Interprete Di Euclide. Firenze: La Nuova Italia.
3. Bokhove, Niels W. 1991. 'Phänomenologie': Ursprung Und Hintergrund Des Terminus Im 18. Jahrhundert, University of Utrecht.
   Distributed by Scientia Verlag (Aalen), 1992.
   Review by Ignacio Angelelli, Review of Metaphysics, 47 (1993) pp. 360-62.
   The Third Part is dedicated to the "Development of the term 'phenomenology' in the Eighteenth century" through the detailed study of four authors: Friedrich Christoph Oetinger (1702-1782), Lambert (pp. 191-231), Kant, and John Robison (1739-1805).
4. Ciafardone, Raffaele. 1975. J. H. Lambert E La Fondazione Scientifica Della Filosofia. Urbino: Argalia.
5. Debru, Claude. 1977. Analyse Et Représentation. De La Méthodologie À La Théorie De L'espace: Kant Et Lambert. Paris: Vrin.
6. Laywine, Alison. 2010. Kant and Lambert on Geometrical Postulates in the Reform of Metaphysics in Discourse on a New Method. Reinvigorating the Marriage of History and Philosophy of Science, edited by May, Domski and Michael, Dickson, 113-133. Chicago: Open Court.
7. Preite, Maria dello. 1979. L'immagine Scientifica Del Mondo Di Johann Heinrich Lambert. Razionalità Ed Esperienza. Bari: Dedalo.
8. Schiewer Gesine, Lenoire. 1996. Cognitio Symbolica. Lamberts Semiotische Wissenschaft Und Ihre Diskussion Bei Herder, Jean-Paul Und Novalis. Tübingen: Niemeyer.
9. Todesco, Fabio. 1987. Riforma Della Metafisica E Sapere Scientifico. Saggio Su J. H. Lambert (1728-1777). Milano: Franco Angeli.
   Bibliografia lambertiana (1944-1987): pp. 257-326.
10. Wolters, Gereon. 1980. Basis Und Deduktion. Studien Zur Entstehung Und Bedeutung Der Theorie Der Axiomatischen Methode Bei J. H. Lambert (1728-1777). Berlin: Walter de Gruyter.
11. ———. 1985. Some Pragmatic Aspects of the Methodology of Johann Heinrich Lambert in Change and Progress in Modern Science. Papers Related to and Arising from the Fourth International Conference on History and Philosophy of Science, Blacksburg, Virginia, November 1982, edited by Pitt, Joseph C., 133-170. Dordrecht: Reidel.

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