Theory and History of Ontology

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  • "History Logic" and "Bibliographia" are my other websites. "Table of Contents" gives the list of the pages, for other indexes see the "Sitemap". "Modern Ontologists" contains a table with links to the pages on the most important philosophers of the 19th and 20th centuries who have written on ontology. The "Search" function can be used to find a particular author or subject.


Selected Bibliography on the History of the Theories of Non-Existent Objects


  1. "Le Problème Du Non-Être Dans La Philosophie Antique." 1990. Revue de Théologie et de Philosophie no. 122:297-432.

    Actes du Colloque de philosophie antique tenu à Geève les 2 et 3 novembre 1989 à la mémoire d'Henri Joly

  2. Adams, Marilyn McCord. 1977. "Ockham's Nominalism and Unreal Entities." Philosophical Review no. 76:144-176.

  3. Amerini, Fabrizio, and Rode, Christian. 2009. "Franciscus De Prato's Tractatus De Ente Rationis. A Critical Edition with a Historico-Philosophical Introduction." Archives d'Histoire Doctrinale et Littéraire du Moyen Age no. 76:261-312.

    "This paper provides a critical edition of Francis of Prato’s Treatise on Being of Reason ( Tractatus de ente rationis). It is prefaced by a historico-philosophical introduction. Francis’s Treatise is one of the first Italian reactions to the diffusion of William of Ockham’s philosophy of language and logic. Francis argues here against Ockham’s reduction of being of reason to acts of cognition, accounted for as items existing ‘subjectively’ (subiective) in the mind. By contrast, following Thomas Aquinas and Hervaeus Natalis, he proposes a relational and ‘objective’ account of being of reason."

  4. Ashworth, Earline Jennifer. 1977. "Chimeras and Imaginary Objects: A Study in the Post-Medieval Theory of Signification." Vivarium no. 15:57-79.

    Reprinted as chapter III in: Studies in Post-Medieval Semantics.

  5. Azanza, Ana. 1995. "La Polemica De Pedro De Atarrabia (M. 1347) Con Pedro Aureolo (M. 1322) Sobre La Intuicion Del No-Existente." Revista Espanola de Filosofia Medieval no. 2:71-78.

  6. Bakaoukas, Michael. 2003. Nothing Exists. A History of the Philosophy of Non-Being: Xlibris Corporation.

  7. Benoist, Jocelyn. 2001. Représentations Sans Objet. Aux Origines De La Phénoménologie Et De La Philosophie Analytique. Paris: Presses Universitaires de France.

  8. Berti, Enrico. 1983. "Quelques Remarques Sur La Conception Aristotélicienne De Non-Être." Revue de Philosophie Ancienne no. 2:115-142.

  9. ———. 1990. "Être Et Non-Être Chez Aristote: Contraires Ou Contradictoires?" Revue de Théologie et de Philosophie no. 122:365-374.

  10. Beuchot, Mauricio. 1987. Metafísica. La Ontologia Aristotélico-Tomista De Francisco De Araújo. Ciudad de Mexico: Universidad Nacional Autónoma de Mexico UNAM.

  11. Biard, Joël. 1985. "La Signification D'objets Imaginaires Dans Quelques Textes Anglais Du 14e Siècle (Guillaume De Heytesbury, Henry Hopton)." In The Rise of British Logic. Acts of the Sixth European Symposium of Medieval Logic and Semantics. Balliol College, Oxford, 19-24 June 1983, edited by Lewry, Patrick Osmund, 265-283. Toronto: Pontifical Institute of Medieval Studies.

  12. Blackwell, Daniel F. 1988. Non-Ontological Constructs. The Effects of Abaelard's Logical and Ethical Theories of His Theology: A Study in Meaning and Verification. Bern: Peter Lang.

  13. Boehner, Philotheus. 1948. " Notitita Intuitiva of Non-Existents According to Peter Aureoli, O.F.M. (1322)." Franciscan Studies no. 6:388-416.

  14. Bostock, David. 1984. "Plato on 'Is Not' ( Sophist 254-9)." Oxford Studies in Ancient Philosophy no. 2:89-119.

  15. Brunschwig, Jacques. 1990. "Sur Une Façon Stoicienne De Ne Pas Être." Revue de Théologie et de Philosophie no. 122:389-404.

  16. Cantens, Bernardo J. 2003. "Suárez on Beings of Reason: What Kinds of Beings ( Entia) Are Beings of Reason, and What Kind of Being ( Esse) Do They Have?" American Catholic Philosophical Quarterly no. 77:171-187.

    "Beings of reason or non-existent objects have always been a source of mind-boggling paradoxes that have vexed philosophers and thinkers in the past and present. Consider Bertrand Russell's paradox: 'if A and B are not different, then the difference between A and B does not subsist. But how can a non-entity be the subject of a proposition?' Or Meinong's paradox: 'There are objects of which it is true that there are no such objects.' At the root of these troubling conundrums are two basic questions: What are beings of reason? What kind of existence do they have? Francisco Suárez was well aware that a solution to the metaphysical questions concerning the essential character of beings of reason and their ontological status would serve as the key to solving the puzzles and paradoxes just described. A solution to these metaphysical questions would also bring about an understanding of how we talk about beings of reason and other problems that they give rise to in the philosophy of language. In this paper, I present Suárez's view on the nature and ontological status of beings of reason and clarify some of the following questions: What kind of beings ( entia) are beings of reason? What kind of being ( esse) do beings of reason have? This latter concern is related to the following metaphysical issues: What are real beings? What is the nature and ontological status of possible beings? What is the distinction between real beings, actual beings, and possible beings?"

  17. Carson, Scott. 2000. "Aristotle on Existential Import and Non Referring Subjects." Synthese no. 124:343-360.

  18. Cartwright, Richard L. 1960. "Negative Existentials." Journal of Philosophy no. 57:629-639.

    Reprinted in: R. L. Cartwright, Philosophical Essays, Cambridge: MIT Press, 1987, pp. 21-31.

  19. Caston, Victor. 1999. "Something and Nothing: The Stoics on Concepts and Universals." Oxford Studies in Ancient Philosophy no. 17:145-213.

  20. Cocchiarella, Nino. 1982. "Meinong Reconstructed Versus Early Russell Reconstructed." Journal of Philosophical Logic no. 11:183-214.

  21. Coombs, Jeffrey S. 1994. "John Poinsot on How to Be, Know, and Love a Non-Existent Possible." American Catholic Philosophical Quarterly no. 68 (3):321-335.

  22. Couloubaritsis, Lambros. 1990. "La Logique Du Mythe Et La Question Du Non-Être." Revue de Théologie et de Philosophie no. 122:323-340.

  23. Cova, Luciano. 1976. "Francesco Di Meyronnes E Walter Catton Nella Controversia Scolastica Sulla 'Notitia Intuitiva De Re Non Existente'." Medioevo no. 2:227-252.

  24. Dancy, Russell M. 1991. Two Studies in the Early Academy. New York: State University of New York Press.

    Contents: Preface IX, Introduction XI-XII; Study I. Predication and immanence: Anaxagoras, Plato, Eudoxus, and Aristotle 3; Study II. Ancient non-beings: Speusippus and others 63; Notes 121; Bibliography 179; Index locorum 205; General index 215.

  25. Davis, Leo Donald. 1975. "The Intuitive Knowledge of Non-Existents and the Problem of Late Medieval Skepticism." New Scholasticism no. 49:410-430.

  26. Demonet, Marie-Lucie. 2002. "Les Êtres De Raison, Ou Les Modes D'être De La Littérature." In Res Et Verba in Der Renaissance. Proceedings of a Colloquium Held at Herzog August Bibliothek Wolfenbüttel in 1998, edited by Kessler, Eckhard and Maclean, Ian, 177-195. Wiesbaden: Harrassowitz Verlag.

  27. Doyle, John Patrick. 1994. "Poinsot on Knowability of Beings of Reason." American Catholic Philosophical Quarterly no. 68 (3):337-362.

  28. ———. 1995. "Another God, Chimerae, Goat-Stags, and Man-Lions: A Seventeenth-Century Debate About Impossible Objects." Review of Metaphysics no. 48 (4):771-808.

  29. Ebbesen, Sten, and Pinborg, Jan. 1982. "Thott 581 40, or De Ente Rationis." In English Logic in Italy: 14th and 15th Centuries, edited by Maierù, Alfonso, 111-146. Napoli: Bibliopolis.

  30. Fernández-Rodríguez, José Luis. 1972. El Ente De Razón En Francisco Araújo. Pamplona: Ediciones Universidad de Navarra.

  31. ———. 1994. "El "Ens Rationis", Un Caso De Objeto Puro." Anuario Filosófico no. 27:297-318.

    " Abstract. This article tries to show that the ens rationis is nothing else but one of the most relevant cases of the pure object. To reach this conclusion, the different position regarding the pure object as those of Meinong, Hartmann Millán-Puelles and the Schoolmen are examined."

  32. ———. 1997. "La Etiología Del Ente De Razón." Philosophica no. 19-20:109-120.

  33. ———. 1997. "Tipología Del Ente De Razón." Anuario Filosófico no. 30:361-379.

  34. Gilson, Etienne. 1952. Being and Some Philosophers. Toronto: Pontifical Institute of Mediaeval Studies.

  35. González, Angel Luis. 1994. "Lo Meramente Posible." Anuario Filosófico no. 27:345-364.

    "Abstract. The merely possible is a sort of pure object, framed in the background of the general chart of the unreal feasibly non-existent, and defined by the uncontradictoriety and the fitness for to exist. In this paper are studied, according to Millán-Puelles, some objections and controversies about that concept. It is enphasized the theory of Leibniz concerning to the exigentia existentiae of the possible. And, also, the speculative importance of that notion in order to Absolute's attributes and the metaphysic concept of creation." p. 345

  36. Grossmann, Reinhardt. 1969. "Non-Existent Objects: Recent Work on Brentano and Meinong." American Catholic Philosophical Quarterly no. 6:17-32.

  37. ———. 1974. "Meinong's Doctrine of the "Aussersein" of the Pure Object." Nous no. 8:67-82.

  38. ———. 1984. "Nonexistent Objects Versus Definite Descriptions." Australasian Journal of Philosophy no. 62 (4):363-377.

    "Some years ago, I published an article about Meinong's theory of objects. (1) I listed there four main theses of Meinong's view:

    (1) The golden mountain (and other nonexistents) has no being at all.

    (2) Nevertheless, it is a constituent of the fact that the golden mountain does not exist.

    (3) Furthermore, it has such ordinary properties as being made from gold.

    (4) Existence is not a constituent of any object.

    And I argued in that paper that only thesis (1) is true. In particular, I insisted that (3), which I consider to be the most characteristic feature of Meinong's view, is false.

    Since then, there have been quite a few discussions of Meinong's view. I would like, in response to some of these works, to reiterate my earlier criticism of Meinong. My purpose is threefold. Firstly, I would like to state once more my own view, which is a version of Russell's theory of definite descriptions, as clearly as possible. Secondly, I shall defend my past contention that the golden mountain is not golden against some recent objections. And thirdly and most importantly, I want to describe the dialectic of the philosophical problem as I perceive it. It seems to me to be an exasperating shortcoming of the discussion that most participants do not clearly state the basic options and their reasons for preferring some to others."

    (1) Meinong's Doctrine of the Aussersein of the Pure Object', Noüs, 8 (1974, pp. 67-81. See also my Meinong (Routledge and Kegan Paul, London, 1974).

  39. Habib, Nicholas. 1985. "A Medieval Perspective on the Meaningfulness of Fictitious Terms: A Study of John Buridan." Franciscan Studies no. 45:73-82.

  40. Hintikka, Jaakko. 1966. "Studies in the Logic of Existence and Necessity. I: Existence." Monist no. 50:55-76.

  41. ———. 1984. "Are the Nonexistent Objects? Why Not: But Where Are They?" Synthese:451-458.

  42. Hunter, Daniel. 1981. "Reference and Meinongian Objects." Grazer Philosophische Studien no. 14:23-36.

  43. Jacquette, Dale. 1982. "Meinong's Theory of Defective Objects." Grazer Philosophische Studien no. 15:1-19.

  44. ———. 1989. "Mally's Heresy and the Logic of Meinong Object Theory." History and Philosophy of Logic no. 10:1-14.

  45. Jadacki, Jacek Juliusz. 2003. "On What Seems Not to Be." In From the Viewpoint of the Lvov-Warsaw School, 19-27. Amsterdam: Rodopi.

  46. John, of St.Thomas (John Poinsot). 1949. "Entia Rationis and Second Intentions." New Scholasticism no. 23:395-413.

    Translated from Latin by John J. Glanville. Donald G. Hollenhorst and Yves R. Simon

  47. Kelley, Francis. 1978. "Some Observations on the 'Fictum' Theory in Ockham and Its Relation to Hervaeus Natalis." Franciscan Studies no. 38:260-282.

  48. Klima, Gyula. 1993. "The Changing Role of Entia Rationis in Mediaeval Semantics and Ontology: A Comparative Study with a Reconstruction." Synthese no. 96:25-58.

    "In this paper I want to argue for two theses concerning entia rationis. My first thesis is that entia rationis, in what I would call the via antiqua (1) sense, are objects of thought and signification, required by a certain kind of semantics, but undesirable as objects simpliciter in ontology. My second thesis is that this systematic role of entia rationis in the via antiqua tradition of mediaeval thought was simply eliminated by the advent of Ockhamist semantics, which opened the way towards a radical reinterpretation of the concept of entia rationis and towards a new research programme for ontology.

    In the next section of this paper, therefore, I start my discussion with a case study of the systematic role played by entia rationis in the Philosophy of St. Thomas Aquinas, a typical representative of the via antiqua tradition, occasionally drawing parallels with and taking illustrations from the works of other mediaeval thinkers, too. (2) In the third section I give a systematic account of all kinds of entia rationis against the background of a comprehensive semantic theory constructed in the spirit of the via antiqua tradition. In the fourth section I describe the ways William Ockham's approach changed this semantic background, and examine how these changes influenced the concept of entia rationis. In the concluding section of the paper I present a simple formal reconstruction of what I take to be Ockham's basic innovations in semantics, and discuss briefly the new ontological programme it initiated."

    (1) One of course has to be very cautious when applying such an expression so much involved in scholarly debate. In the rest of this paper I want to use it in a very restricted, technical sense, referring to a particular way of constructing semantic theory, sharply distinguishable from Ockham's and his followers' way (both to be described later). What

    I think may justify such a usage is the clear connection of these ways of doing semantics with the manners in which broader philosophical, theological, and methodological issues were treated in the two great trends getting separated later in mediaeval thought. Indeed, this paper may perhaps serve as a modest contribution to the characterisation of the two viae from the point of view of the connections between semantics and ontology. As to the debates concerning the proper characterisation of via antiqua vs. via moderna, see, e.g., Moore (1989).

    (2) To be sure, by presenting Aquinas's views as representative of what I call 'via antiqua semantics' I do not want to deny the immense variety of semantic views in mediaeval philosophy even before Ockham. I take Aquinas's views as typical, however, as contrasted with Ockham's, precisely in those of their features that rendered the via antiqua framework unacceptable for Ockham.

  49. Kobusch, Theo. 1996. "Ens Inquantum Ens Und Ens Rationis. Ein Aristotelisches Problem in Der Philosophie Des Duns Scotus Und Wilhelm Ockham." In Aristotle in Britain During the Middle Ages, edited by Marenbon, John, 157-175. Turnhout: Brepols.

    Proceedings of the International conference at Cambridge 8-11 April 1994 organized by the Société Internationale pour l'Étude de la Philosophie Médiévale

  50. Kraus, Oskar. 1929. "Gegen Entia Rationis, Sogennante Irreale Oder Ideale Gegenstände." Philosophische Hefte no. 2:257-273.

  51. Lambertini, Roberto. 1989. "Resurgant Entia Rationis. Matthaeus De Augubio on the Object of Logic." Cahiers de l'Institut du Moyen-Âge Grec et Latin no. 59:3-60.

  52. Landini, Gregory. 1990. "How to Russell Another Meinongian: A Russellian Theory of Fictional Objects Versus Zalta's Theory of Abstract Objects." Grazer Philosophische Studien no. 37:93-122.

  53. Lehrer, Keith. 1987. "Beyond Impressions and Ideas: Hume Versus Reid." Monist no. 70:383-397.

  54. Letoublon, François. 1990. "La Notion De Non-Être Dans L'histoire De La Languq Grecque Archaique." Revue de Théologie et de Philosophie no. 122:313-322.

  55. Libera, Alain de. 1997. "Subsistance Et Existence: Porphyre Et Meinong." Revue de Métaphysique et de Morale:167-192.

  56. ———. 2002. La Référence Vide.Théories De La Proposition. Paris: Presses Universitaires de France.

  57. Lombardo, Mario Gaetano. 1995. La Forma Che Dà L'essere Alle Cose. Enti Di Ragione E Bene Trascendentale in Suárez, Leibniz, Kant. Milano: Istituto Propaganda Libraria.

  58. Mally, Ernst. 1989. "On the Objects Independence from Thought." Man and World no. 22:215-231.

    Translation and Commentary by Dale Jacquette

  59. Mares, Edwin D. 1997. "Who's Afraid of Impossible Worlds?" Notre Dame Journal of Formal Logic no. 38 (4):516-526.

  60. McGrade, Arthur S. 1985. "Plenty of Nothing: Ockham's Commitment to Real Possibles." Franciscan Studies no. 45:145-156.

  61. Millán-Puelles, Antonio. 1996. The Theory of the Pure Object. Heidelberg: Universitätsverlag C. Winter.

    Original Spanish edition: Teoría el objeto puro, Coleccíon Cuestiones Fundamentales (Madrid: Ediciones RIALP, 1990). Translated and edited by Jorge García-Gómez

  62. Murault, André de. 1990. "L'être Du Non-Être En Perspective Aristotelicienne." Revue de Théologie et de Philosophie no. 122:375-388.

  63. Novotný, Daniel D. 2006. "Prolegomena to a Study of Beings of Reason in Post-Suarezian Scholasticism, 1600-1650." Studia Neoaristotelica no. 3:117-141.

    "In 1597 Francisco Suárez published a comprehensive treatise on beings of reason (entia rationis) as part of his Disputationes metaphysicae. Subsequent scholastic philosophers vigorously debated various aspects of Suárez's theory. The aim of this paper is to identify some of the most controversial points of these debates, as they developed in the first half of the seventeenth century. In particular, I focus on the intension and the extension of 'ens rationis', its division (into negations, privations and relations of reason) and its causes. Additionally, I will discuss how Suárez's views sparked a number of debates within the classical view, debates which ultimately led to the emergence of various alternative theories, especially among the Jesuits. These non-classical views radically revise the previous classical conception of beings of reason."

  64. ———. 2013. Ens Rationis from Suárez to Caramuel. A Study in Scholasticism of the Baroque Era. New York: Fordham University Press.

    "Beings of reason are impossible intentional objects, such as blindness and square-circle. The first part of this book is structured around a close reading of Suarez's main text on the subject, namely Disputation 54. The second part centers on texts on this topic by other outstanding philosophers of the time, such as the Spanish Jesuit Pedro Hurtado de Mendoza (1578-1641), the Italian Franciscan Bartolomeo Mastri (1602-73), and the Spanish-Bohemian-Luxembourgian polymath Juan Caramuel de Lobkowitz (1606-82)."

  65. O'Brien, Denis. 1999. "La Matière Chez Plotin: Son Origine, Sa Nature." Phronesis no. 44:45-71.

  66. O'Meara, Dominic. 1990. "La Question De L'être Et Du Non-Être Des Objets Mathématiques Chez Plotin Et Jamblique." Revue de Théologie et de Philosophie no. 122:405-416.

  67. Perszyk, Kenneth J. 1993. Nonexistent Objects: Meinong and Contemporary Philosophy. Dordrecht: Kluwer Academic Publishers.

  68. Philippe, Marie-Dominique. 1975. "Originalité De "L'ens Rationis" Dans La Philosophie De Saint Thomas." Angelicum no. 52 (1):91-124.

    "Si Aristote a eu le mérite de distinguer avec beaucoup de netteté l'art de la logique de la philosophie elle-même, considérant cet art comme un organon, un instrument de la pensée, saint Thomas, commentateur d'Aristote, continue son effort; et dans une perspective critique il précise que si la philosophie regarde l'ens naturae, l'ens extra animam, la logique, elle, considère l'ens rationis, ce qui ne peut naître que dans notre connaissance intellectuelle (1).

    Examinons ici les principaux textes où saint Thomas expose sa pensée sur ce point, pour essayer d'en saisir toute la signification et, à partir de là, mieux comprendre le réalisme de sa métaphysique. Car si l'ens naturae ne se définit pas par l'ens rationis - c'est plutôt l'inverse qui a lieu, puisque l'ens per se est l'ens extra animam, il peut cependant être mieux manifesté, pour nous, grâce à l'ens rationis. Il y a là quelque chose d'analogue à ce qui a lieu entre f'ens naturae et l'ens artificiale (qui peut, lui aussi, être appelé ens rationis en un sens élargi): l'ens artificiale se définit en fonction de l'ens naturae, et non l'inverse; mais la comparaison des deux nous aide à mieux saisir ce qu'est l'ens naturae au sens fondamental et premier." p. 91

    (1) Cf. Comm. Mét., IV, 4, n. 574.

    (2) Comm. Mét., VII, 1, n. 1245.

  69. Priest, Graham. 1997. "Sylvan's Box: A Short Story and Ten Morals." Notre Dame Journal of Formal Logic no. 38 (4):573-582.

  70. Przelecki, Marian. 1981. "On What There Is Not." Diaectics and Humanism no. 8:123-129.

  71. Putallaz, François-Xavier. 1983. "Autour De La Connaissance Intuitive Des Non-Existants Chez Ockham." Freiburger Zeitschrift für Philosophie und Theologie no. 30:447-467.

  72. Rapaport, William J. 1985. "Terence Parsons' "Nonexistent Objects"." Nous no. 19:255-271.

  73. ———. 1986. "Non-Existent Objects and Epistemological Ontology." Grazer Philosophische Studien no. 25/26:61-95.

    "This essay examines the role of non-existent objects in "epistemological ontology" - the study of the entities that make thinking possible. An earlier revision of Meinong's Theory of Objects is reviewed, Meinong's notions of Quasisein and Aussersein are discussed, and a theory of Meinongian objects as "combinatorially possible" entities is presented."

  74. Raspa, Venanzio. 1996. "Su Ciò Che Non Esiste. Da Bolzano a Meinong: Un Excursus Nella Filosofia Austriaca." Studi Urbinati no. 67:115-201.

  75. Read, Stephen. 1977. "The Objective Being of Ockham's Ficta." Philosophical Quarterly no. 27:14-31.

  76. Rode, Christian. 2001. "Sein Oder Nichtsein. Hervaeus Natalis Und Wilhelm Von Ockham Über Das Ens Rations." In Umbrüche: Historische Wendepunkte Der Philosophie Von Der Antike Bis Zur Neuzeit, edited by Kahnert, Klaus and Mojsisch, Burkhard, 77-98. Amsterdam: B. R. Grüner.

  77. ———. 2004. Franciscus De Prato. Facetten Seiner Philosophie Im Blick Auf Hervaeus Natalis Und Wilhelm Von Ockham. Stuttgart: Franz Steiner.

  78. Roncaglia, Gino. 1994. " Utrum Impossibile Sit Significabile: Buridano, Marsilio Di Ighen E La Chimera." In Filosofia E Teologia Nel Trecento. Studi in Ricordo Di Eugenio Randi, edited by Bianchi, Luca, 259-282. Louvain-la-Neuve: Fédération Internationale des Instituts d'Études Médiévales.

  79. ———. 1995. "Smiglecius on " Entia Rationis"." Vivarium no. 33:27-49.

  80. Rosenkrantz, Gary. 1990. "Reference, Intentionality and Nonexistent Entities." Philosophical Studies no. 58:183-195.

  81. Rovira, Rogelio. 2000. "La Quidddades Paradójicas. Sobre La Contribución De Antonio Millán-Puelles a La Doctrina Clasica Del Ente De Razón." Pensamiento no. 56:265-284.

  82. Schmidt, Robert. 1963. "The Translation of Terms Like Ens Rationis." Modern Schoolman no. 41:73-75.

  83. Sillitti, Giovanna. 1980. Tragelaphos. Storia Di Una Metafora E Di Un Problema. Napoli: Bibliopolis.

  84. Tachau, Katherine. 2001. "Peter Aureol on Intentions and the Intuitive Cognition of Non-Existents." Cahiers de l'Institut du Moyen-Âge Grec et Latin no. 44:122-150.

  85. Tweedale, Martin. 1967. "Abailard and Non-Things." Journal of the History of Philosohy no. 5:329-342.

  86. Vela Utrilla, Juan F. 1948. "El Ente De Razón En Suàrez." Pensamiento no. 4:271-303.

  87. Vossenkühl, Wilhelm. 1985. "Ockham and the Cognition of Non-Existants." Franciscan Studies no. 45:33-46.

  88. Wells, Norman J. 1983. "Francisco Araujo, Op, on the Eternal Truths." In Graceful Reason. Essays in Ancient and Medieval Philosophy Presented to Joseph Owens, Cssr on the Occasion of His Seventy-Fifth Birthday and the Fiftieth Anniversary of His Ordination, edited by Gerson, Lloyd, 401-417. Toronto: Pontifical Institute of Mediaeval Studies.

  89. Wettstein, Howard. 1984. "Did the Greeks Really Worship Zeus?" Synthese no. 60:439-450.

  90. Willing, Anthony. 1985. "Buridan and Ockham: The Logic of Knowing." Franciscan Studies no. 45:47-56.

  91. Wippel, John F. 1981. "The Reality of Nonexistent Possibles According to Thomas Aquinas, Henry of Ghent, and Gdofrey of Fontanes." Review of Metaphysics no. 34:729-758.