A Reconsideration of the Identity and Inherence Theories of the Copula

A Reconsideration of the Identity and Inherence Theories of the Copula JOHN MALCOLM SCHOLARS CONCERNEDWITHMEDIEVALLOGIChave recently made much of a distinction between two alleged theories as to the logical function of the copula: the identity theory and the inherence theory. Ernest Moody claims that up to the fourteenth century the copula was analyzed in terms of the inherence theory, whereas the identity theory of the copula was "adopted by practically all of the logicians of the fourteenth century.'" L. M. De Rijk uses the distinction in his account of Abelard, asserting that Abelard embraced, in turn, these two different theories of the copula. In Logica Modernorum De Rijk writes: "In the days of Peter Abailard the controversy ab6ut the meaning of the copula in an affirmative proposition was still eagerly discussed. We find in Abailard two theories. In his Logica Ingredientibus he turns out to be an adherent to the inherence theory .... However, in his Dialectica the author transferred the pith of the matter to the identity theory. ''2 This interpretation is repeated by Pinborg in his Logik und Semantik im Mittelalter. 3Pinborg, in fact, makes the distinction a veritable leitmotiv throughout his study.' My thesis will be that the identity-inherence dichotomy has been applied much too broadly and uncritically, for it does not hold for cases of accidental predication. I shall first try to get an adequate formulation of the two theories and shall then contrast them with what I shall call the normal theory of accidental predication. I then turn to Abelard and maintain that he does not go from an inherence theory in the Logica lngredientibus5to an identity theory in the Dialectica but, rather, holds to the normal theory in both works. After this I shall examine Ockham and his followers and shall conclude that they are not, as is usually supposed, identity theorists. The question remains whether there are any bona fide inherence theorists. I shall suggest that the attempts to consider Aquinas and Ferrer to be such are inconclusive, but I shall not, in contrast with the alleged identity theorists, give a conclusive rebuttal of this possibility. Finally, I shall indicate that the true scope of the controversy ' Truth and Consequence in Mediaeval Logic (Amsterdam: North-Holland, 1953), p. 36. J 2 vols. (Assen: Van Gorcum, 1967), 2, pt. 1:105 (hereafter cited as LM): cf. Peter Abelard, Dialectica, ed.: De Rijk, 2nd ed. (Assen: Van Gorcum, 1970), p. xlii, secs. 6.34, 6.44. 3(Stuttgart-Bad Cannstatt: Frommann-Holzboog, J972), p. 53. ' See, e.g., pp. 53, 65, 88, 98, 136. The Logica Ingredientibus is contained in Peter Abaelards Philosophische Schriften, ed. B. Geyer, in Beitrdge zur Geschichte tier Philosophie und Theologie des Mittelalters 21 (MUnster: Aschendorffschen Verlagsbuchhandlung, 1919-33). [3831 384 HISTORY OF PHILOSOPHY between identity and inherence should be limited to essential predication. Since the crucial case for my thesis is the predication of accidents, I shall devote my attention to the time-honored paradigm statement "Socrates is white." Before I begin, let me briefly discuss the cofinection of the present topic to one that is of considerably wider immediate interest to philosophers, that of the nature of universals. In considering the relation of the inherence and identity theories to realism and nominalism ! shall anticipate my analyses of these theories and borrow (from p. 386 below) the principle that the identity theory denies the inherence of a predicate form in a subject while the inherence theory asserts the existence of such a form. Given this distinction, we may infer that the identity theory and realism are clearly incompatible. If there is no predicate form inhering in the subject, then there is no such universal nature. The inherence theory is, however, consistent with both realism and nominalism. If the inhering form is universal, we have realism; if particular , nominalism (or conceptualism). We may conclude that the only theory consistent with realism is that of inherence, but it does not imply it, for we need the additional assumption that the inhering form is universal. The Identity Theory De Rijk defines the identity theory as follows: "This theory holds the copula of an affirmative proposition to state that the subject-term and the...