Directory:Logic Museum/Every man is an animal
IS 'EVERY MAN IS AN ANIMAL' TRUE WHEN NO MAN EXISTS?
Introduction
On this page I am collecting together primary references on the medieval discussion on the question whether 'every man is an animal' is true, when no man exists. The question is closely connected with Terence Parsons' discussion of the O proposition in the Stanford Encyclopedia of Philosophy. Parsons claims that 'For most of the history of Aristotelian logic, logicians assumed that negative particular propositions [i.e. Latin propositions of the form quoddam A est B, standardly represented in English as 'some A is not B'] are vacuously true if their subjects are empty'. I am suspicious of this claim. There is pretty firm evidence that no logician before Abelard even considered the special case where the subject term is empty. There is ample evidence that post-scholastic traditional logicians (i.e. from the seventeenth to the late nineteenth century and later) did not hold the view that Parsons mentions. But there is almost no literature in the high scholastic period on the O proposition, and what references we do have are confusing.
However, it turns out there is an extensive literature on the question of whether the proposition 'Every man is an animal' is true when no man exists (Utrum haec sit vera, homo est animal nullo homine existente), which was a favourite subject of sophism-literature in the late thirteenth century. Alain de Libera (loc. cit), lists 36 texts devoted to this question, which I reproduce below, together with a number of additions of my own. If Parsons' claim is correct, and for most of the history of Aristotelian logic, logicians assumed that negative particular or O propositions are vacuously true if their subjects are empty, it follows they must have thought that universal affirmative propositions are vacuously false if their subjects are empty, since the A and the O propositions are contradictory. So the question hangs upon what the logicians of the high scholastic period thought about 'every man is an animal', when the subject is empty, i.e. no men exist.
The answer is fairly straightforward, and probably what you would expect: they were deeply divided on the subject. The problem is that certain universal propositions seem to be essentially or necessarily true. How could 'every man is an animal' or 'three and four are seven' possibly be false? It is contrary to the view of all philosophers, according to Francisco Suarez, writing at the very end of the scholastic period. Furthermore, great authorities of the Church such as Augustine and Anselm, had said that such propositions are perpetually and eternally true. Augustine says (IV On the Literal Exposition of Genesis, c. 7) 'Six is a perfect number, not because God completed all things in six days, but rather, conversely, the reason God completed things in six days, was because that number is perfect, which would be perfect even if those things did not exist'. Therefore, such propositions should be true, even when their subjects are empty.
However, Aristotelian doctrine, strictly interpreted, requires that such propositions be false when their subjects are empty. A proposition is only true, according to Aristotle, when the combination of terms in the proposition (e.g. 'man' with 'animal') corresponds to some existing combination in reality (e.g. man and animal. Now the proposition 'a man is an animal' is true when a man exists, because the predicate 'animal' belongs to the 'essence' of its subject, man. (An essence is a set of attributes which make that substance the kind of thing it is, thus any essential attribute is necessarily found in the substance to which it belongs). But Aristotle also holds that when the existence of anything ceases, its essence perishes also (ablata existentia, perit essentia).
So, by implication, the composition of things in that essence (man and animal) ceases to be a real composition when the man perishes. But when every man perishes, every combination of man and animal also perishes, therefore a proposition in which a predicate is essentially predicated of a thing is not necessarily or forever true. Aristotelian doctrine seems to imply something which is false and contrary to all philosophical opinion.
Quia si, ablata existentia, perit essentia, ergo propositiones illae in quibus praedicata essentialia de re praedicantur non sunt necessariae neque perpetuae veritatis; consequens autem est falsum et contra omnium philosophorum sententiam. [Suarez]
Opinions were divided on the subject, and the arguments on each side are diverse and interesting. The were some very curious views on the subject. Siger of Brabant thought the proposition would be false if there were no men, but as men necessarily exist, the proposition is necessarily true. (He thought that every man must have parents, from whom the essence of man is handed down through the ages, therefore men must always have existed – a false and heretical view, which was condemned in 1277). A number of philosophers, including Scotus, argued that by a syllogism based on opposite propositions, every animal is a substance, some man is not a substance, we derive 'some man is not an animal'. But Aristotle says (Prior Analytics II, 64b7-10) that the conclusion of such a proposition is not possible. Ergo its contradictory, namely 'every man is an animal' is necessary. Boethius of Dacia points out the obvious fallacy in this argument.
Another argument was that the universal proposition is ambiguous between signifying a categorical proposition, in which one existing thing is predicated of another existing thing, and a conditional proposition of the form 'if x is A, x is B'. With no men existing, the former is false, but the latter is true. We find this view as early as the 1250's, defended by William of Sherwood. It is roundly denounced by William of Ockham. We find it again in Vincent Ferrar, and again in Francisico Suarez, and substantially the same view is held by Maritain and other neo-scholastic logicians. Another view, unsurprisingly held by Scotus, is that essence has a separate being, esse essentiae, and that in some sense it does not perish when all the individuals that possess it have perished.
The list of primary references is below. I have located many of these, and they will start to appear in the Logic Museum in the coming months (August-November 2007). There is very little secondary literature on the subject, but it is all the more interesting for that.
Philosophers and dates
Richard the Sophister (fl c 1230-40)
Boethius of Dacia (fl c. 1270-80)
Siger of Brabant (1240 – post 1282)
Simon of Faversham (1260-1306)
John Duns Scotus (1266 – 1308)
William of Ockham (1285 – 1347)
Paul of Venice (1369 - 1429)
Francisco Suarez (1548-1617)
Primary Sources
In approximate date order:
1225? Robert Bacon,Omnis homo de necessitate est animal; [in Syncategorema] ed. H.A.G. Braakhuis, in De 13de Eewse Tractaten &c 120-1, also 'English tracts &c', 162.
c. 1235 Ricardus Sophista, Omne coloratum est; ed. J. Pinborg, in Magister Abstractionum, Cahiers de l’Institut du Moyen Âge grec et latin, 18 (1976), 1-4.
c. 1235 Ricardus Sophista, Omnis homo de necessitate est animal; ed. ed. H.A.G. Braakhuis in 'English Tracts on Syncategorematic Terms &c', 161.
c. 1235 Ricardus Cornubiensis [= Richard the Sophist?], In Sent., ms. Oxford, Balliol 62, fol. 222C-223D; ed F. Pelster, in 'Roger Bacon's Compendium Studii theologiae und der Sentenzkommentar des Richardus Rufus …', 275-79.
Anon., Utrum haec sit vera 'Caesar est homo Caesare non existente, ms. London, B.L. Arundel 383, fol. 207vb; ed S. Ebbesen, in 'Stray Quaestiones and Sophismata in British and French Manuscripts', Cahiers de l'Institut du Moyen Age grec et latin, 57 (1988), p. 70-2.
Anon., Utrum haec sit vera, 'Homo est animal' homine non exsistente, ms. Cambridge, Peterhouse 152, fol. 49ra –vb; ed. A. Zimmermann, in 'Eine anonyme Quaestio: 'Utrum haec sit vera 'Homo est animal' homine non exsistente', Archiv fur Geschichte der Philosophie, 49 (1967), p. 184-8.
c. 1250 Anon., Omnis homo de necessitate est animal, ms. Paris, Nat. lat. 16135, fol. 11rb-12vb.[<a href = "selectionsnullohomine.htm#anon">extracts</a>]
Anon Omnis homo est, ms. ParisNat. lat. 16135, fol. 49vb-52vb.
Anon Omnis homo de necessitate est animal, ms. ParisNat. lat. 16135, fol. 52vb-62vb.
after 1250 Anon Omnis homo de necessitate est animal, ms. ParisNat. lat. 16135, fol. 99rb-103vb.
Anon., Sor est Sor mortuus, ms. ParisNat. lat. 16135, fol. 107va-108rb.
c 1250 Nicholas of Paris, Syncategoremata, Braakhuis De 13de Eewse Tractaten over Syncategorematische Termen, II: Uitgave van Nicolaas van Parij's Sincategoreumata, Meppel, 1979.
c. 1250 William of Sherwood, Introductiones in Logicam; ed. Ch. H. Lohr, P. Kunze & B. Mussler, in 'William of Sherwood, Introductiones in Logicam, Critical Text, Traditio, 39 (1983), 222-99.
c. 1250 William of Sherwood, Syncategoremata; ed. J.R.O'Donnell, C.S.B., in 'The Syncategoremata of William of Sherwood', Medieval Studies, 3 (1941), 46-93.
c. 1250 Robert Kilwardby, Omnis homo de necessitate est animal; ed. S. Ebbesen & J. Pinborg, in 'Studies in the Logical Writings attributed to Boethius of Dacia', Cahiers de l’Institut du Moyen Âge grec et latin, 3 (1970), 37-40 [<a href = "selectionsnullohomine.htm#kilwardby ">extracts</a>].
c. 1250 Robert Kilwardby, Omnis Phoenix est; ed. H.A.G. Braakhuis, in 'Kilwardby versus Bacon? The Contribution to the Discussion on Univocal Signification of Beings and Non-Beings Found in a Sophisma attributed to Rober Kilwardby', in Medieval Semantics and Metaphysics. Studies dedicated to L.M. De Rijk, PhD on the Occasion of his 60th birthday, ed. E.P. Bos, (Artistarium, Supplementa 2), Nijmegen, Ingenium Publishers, 1985, 126-142 [extracts].
? 1250 Robert Kilwardby (pseudo), In Priscianum Maiorem; ed K.M. Fredborg, N.J. Green-Pedersen, L. Nielsen & J. Pinborg, Cahiers de l’Institut du Moyen Âge grec et latin, 15 (1975), 1-143.
c. 1250 Roger Bacon, Summulae dialectices I-II; ed. A. de Libera, in 'Les Summulae dialectices de Roger Bacon. I-II, De Termino. De Enuntiatione' AHDLMA, 53 (1986), 139-289.
c. 1250 Roger Bacon, Summulae dialectices III; ed. A. de Libera, in 'Les Summulae dialectices de Roger Bacon. III, De argumentatione' AHDLMA, 54 (1987), 171-278.
1260 Roger Bacon, De Signis; ed. K.M. Fredborg, L. Nielsen & J. Pinborg, in 'An Unedited Part of Roger Bacon's Opus Maius: De Signis', Traditio, 34 (1978), 75-136.
1265 Peter of Cornwall, Omnis homo est; ed S. Ebbesen, in 'Talking about what is no more …' Cahiers de l’Institut du Moyen Âge grec et latin, 55 1987), 139-54.
c. 1265 Siger of Brabant, Omnis homo de necessitate est animal; ed. B. Bazan, in Siger de Brabant. Ecrits de logique, de morale et de physique. Edition critique, (Philosophes medievaux, 14) Louvain, Publications universitaires-Paris, Beatrice-Nauwelaerts, 1974, 43-52.
c. 1265 Siger of Brabant, Quaestio Utrum haec sit vera: 'Homo est animal', nullo homine existente; ed. B. Bazan, op. cit., 53-9.
c. 1265 Siger of Brabant, Quaestiones logicales; ed. B. Bazan, op. cit., 60-66.
c. 1265 Siger of Brabant, 'Utrum nomen idem significet et univoce re existente et non existente', in Quaestiones in Metaphysicam; ed. Graiff, Questions sur la Metaphysique, Louvain 1948, 224-9
c. 1270. Boethius of Dacia, Omnis homo de necessitate est animal; ed M.Grabmann, in Die sophismataliteratur des 12 und 13 Jahrhunderts mit Textausgabe eines Sophisma des Boethius von Dacien, BeitrGPhThMa, 36 / 1 (1940) pp. 77-95
c. 1270. Boethius of Dacia, Quaestiones super libros Topicorum II q. 1-5 (Paris, Nat. lat. 16297, fol. 114r, abreviation de Godefried de Fontaines); ed J. Pinborg, in 'Bezeichnung in der Logik des XIII. Jahrhunderts', Miscellanea mediaevalia, 8 (1971), p. 258-9.
c. 1280 Henry of Ghent, Omnis homo de necessitate est animal [in Syncategoremata]; ed. H.A.G. Braakhuis, in De 13de Eewse Tractaten over Syncategorematische Termen, Inleidende Studie, Meppel, 1979, 368 [also in 'English Tracts on Syncategorematic Terms from Robert Bacon to Walter Burley', in English Logic and Semantics from the End of the 12th century to the Time of Ockham and Burleigh. Acts of the 4th European Symposium on Medieval Logic and Semantics. LeidenNijmegen, 23-7 April 1979, ed. H.A.G. Braakhuis, & al. (Artistarium Supplementa, 1), Nimegue, Ingenium Publishers, 1981, 165].
[??] John of Dacia, Summa Grammatica, 'quaestio Utrum ad corruptionem rei vox cadit a sua significatione'; ed A. Otto, (Corpus philosophorum Danicorum Medii Aevi, I/ 1-2), Haunie, 1955, 183-5.
[??] Jean Le Page, Omnis homo de necessitate est animal [in Syncategoremata] ed. H.A.G. Braakhuis ibid 237-40.
1292 Roger Bacon, Compendium Studii Theologiae; ed. Th. S. Maloney, (Studien und Texte zur Geistesgechichte des Mittelalters, 20), Leiden-Koln, 1988.
c. 1295 Simon of Faversham, Quaestiones super Analytica Priora, I, q.56; ed. S. Ebbesen, in 'Talking about what is no more', 158-160.
c. 1295 Simon of Faversham, Quaestiones novae super libro Elenchorum, q. 24.; Utrum haec sit vera 'Caesar est mortuus'; ed S. Ebbesen & al., in Simon of Faversham, Quaestiones super libro Elenchorum (Studies and Texts, 60), Toronto, Pontifical Institute of Medieval Studies, 1984, 161-4.
c. 1295 – John Duns Scotus – In Perihermaneias I
c. 1300 Radulphus Brito, Quaestiones super Analytica Posteriora I, q. 38; ed Ebbesen ibid.
c. 1300 Radulphus Brito, Quaestiones super libr. De interpr., q.4: Utrum vox significet idem re existente et non existente; ed. J. Pinborg, in 'Bezeichnung', 278-81.
c. 1300 Radulphus Brito, Quaestiones super libr. Top. II, q.6: Utrum terminus communis distribuat aequaliter et unica ratione pro suppositis praesentibus, praeteritatis et futuris; ed J. Pinborg, in 'Bezeichnung', 274-75 (extracts).
? 1306 Richard de Clive, Quaestiones Metaphysicae, quaestio Utrum terminus communis significet idem re existente et non existente; ed S. Ebbesen, in 'Talking about what is no more …' 155-7.
1325 William of Ockham II 4 of Summa Logicae.
? 1410 Paul of Venice Logica Magna II.3
1597 Francisco Suarez, Utrum Essentia Creata sit Separabilis a sua Substantia, in Disputationes Metaphysicae, D XXXI, Sectio xii, ed. Vives
Secondary Sources
- Bazan, B., 'La Theorie de la Signification chez Siger de Brabant', in Progress in Linguistic Historiography: Papers from the International Conference on the History of the Language Sciences, Ottawa, August 1978, ed. Konrad Koerner, Amsterdam, Benjamins.
- Ebbesen, S., and Pinborg, J., 'Studies in the Logical Writings attributed to Boethius of Dacia', Cahiers de l'Institut
- du Moyen Age Grec et Latin, University of Copenhagen, 1970
- Henry, D.P. That Most Subtle Question, Manchester 1984. (esp. ch. 5 'Disputed Questions').
- De Libera, Alain 'Roger Bacon et la référence vide. Sur quelques antécédents médiévaux du paradoxe de Meinong', Lectionum varietates, Hommage à Paul Vignaux (1904-1987) (Etudes de philosophie médiévale, LXV), Ed . J. Jolivet, Z. Kaluza, A. de Libera, Paris, Vrin, 1991, p. 85-120.
- Perler, Dominic, Duns Scotus on Signification
- Putallaz, F. And Imbach, R.(1977) Profession Philosophe, Siger de Brabant, Paris: Editions du Cerf.
- Van Steenberghen, F., (1977), Maitre Siger de Brabant, Paris: Publications Universitaires, Louvain, Vander-Oyez S.A
