Heidegger and Plato: Toward Dialogue

Heidegger and the Platonic Concept of Truth

Heidegger’s philosophical training was based on the study of Aristotle, and his interpretation of the Platonic concept of truth was deeply influenced , as I shall argue, by his interpretation of the Aristotelian notion of truth. Accordingly, it is worth starting by outlining the main points of this interpretation, for it enables us to understand and better evaluate Heidegger ’s analogous discourse with regard to Plato.1 In his published works, Heidegger devotes only a few pages to the Aristotelian notion of truth—in Being and Time, Plato’s Doctrine of Truth, and Letter on Humanism. In Being and Time he expounds his conception of truth as “un-concealment,” as opposed to the traditional concept of truth as correspondence. He also denies that Aristotle indicated that truth originated in judgment and attributes to him instead the position that the disclosure originated in the “vision” of ideas that belongs to noêsis; this position , Heidegger claims, was developed by Aristotle in Metaphysics book 9, chapter 10 (BT, 225–26). In Plato’s Doctrine of Truth, on the contrary, Heidegger attributes to Aristotle an ambiguity in determining the essence of truth, given the fact that in Metaphysics 9.10—considered by Heidegger the place where Aristotelian thought on being reaches its apex—unconcealment is the fundamental trait of reality, although the conception of truth as correspondence is also present (“PDT,” 232). Finally, in Letter on Humanism, Heidegger attributes to Metaphysics 9.10 the doctrine that only in the act of apprehension (Vernehmen, noein) can man touch (thigein) being (“LH,” 332). The reason for this change in Heidegger’s position, from approval to criticism of the Aristotelian position, can be understood by examining what he claimed about this matter in some of his university lecture courses that were published posthumously. Heidegger and the Platonic Concept of Truth Enrico Berti 96 Particularly important among these is the course given at Marburg in the winter term 1925–26, namely Logic: The Question of Truth. Its first part is almost wholly devoted to the concept of truth in Aristotle and contains a translation with commentary of all the relative Aristotelian texts, among which the most important is Metaphysics 9.10. This volume, as several others that were published later, confirms what H.-G. Gadamer said in Padua in January 1979, namely, that Heidegger, prior to his famous Kehre, did nothing other than to comment Aristotle, almost giving the impression that he completely identified with him.2 In the course he gave at Marburg, however, Heidegger denies Heinrich Maier’s assertion that for Aristotle the judgment is the place of truth and therefore the fundamental concept of truth for Aristotle is the agreement between thought and reality (Maier 1896). Heidegger shows that for Aristotle the logos apophantikos is essentially a showing, a disclosure, and only secondarily a determining , that is, a predicating (GA 21, 127–35). Consequently, albeit recognizing the almost exclusive presence of truth as correspondence in De interpretatione, Metaphysics 4.7 and 6.4, Heidegger shows that in Metaphysics 9.10, alongside this concept, there is also present a further concept of truth as “un-concealment” which constitutes the peak of Aristotle’s account of fundamental ontology. In this regard, Heidegger (1) contests the position taken by Werner Jaeger (1912), who, following Schwegler and Christ, claims that Metaphysics 9.10 was totally extraneous to book 9 of the Metaphysics; and (2) supports Bonitz (praised for his greater intuition in having taken up the interpretations of Thomas Aquinas and Suarez), according to whom the chapter in question is an integral part of the book in which it is found. Heidegger goes on to criticize the position taken by Ross in his then very recent comment to Metaphysics, because he was not able to decide between the two previous interpretations, and observes that Jaeger himself (1923) is practically a convert to Bonitz’s opinion, for he admits that the chapter had been added by Aristotle himself (GA 21, 170–74). This interpretation of Metaphysics 9.10 was possible only by manipulating the Aristotelian text, under the influence of the Neoplatonic commentator known as pseudo-Alexander and of the aforementioned Hermann Bonitz. In chapter 10 of book 9 there is a particularly important passage, namely 1051b30–33, where Aristotle states: About the things, then, which are essences and exist in actuality, it is not possible to be in error, but only to think them or not to think them [ê noein ê mê]. Inquiry about their “what” takes the form...