10

Critical Questions Raised by Heidegger’s Unpublished Seminars on Aristotle and the Future of the Aristotle/Heidegger Auseinandersetzung

THIS FINAL CHAPTER CANNOT BE, AND DOES NOT pretend to be, a critical evaluation of Heidegger’s seminars on Aristotle, both published and unpublished; that would require a second book. Instead, the first aim here is simply to outline what paths for future research are suggested by the seminars presented in the prior chapters. These paths concern both the thought of Aristotle and the thought of Heidegger. Therefore, I first outline both what Heidegger’s seminars might teach us positively about Aristotle and what their limitations might be in this regard. Secondly, I outline what the seminars might teach us about Heidegger’s own thought and where they might raise questions about it. Everything said here will certainly prove controversial, but the ultimate aim is precisely to use the seminars to provoke discussion that will further our understanding of both Aristotle and Heidegger. Since Heidegger’s own engagement with Aristotle went well beyond the seminars of the 1920s and might have included some rethinking and reevaluation of his earlier readings, the second major aim of the chapter is to briefly summarize the trajectory and content of Heidegger’s later readings and note where we might see a change or evolution in interpretation. This part of the chapter as well will serve only to open avenues for further investigation.

I. What Heidegger’s seminars have to teach us about Aristotle

The reconstruction and analysis of Heidegger’s unpublished seminars on Aristotle has shown them to make a number of positive contributions and challenges to scholarship on Aristotle. These can be summarized as follows:

• The inquiry in De Anima, identifiable neither with “biology” in the contemporary sense nor “philosophy of mind” nor “psychology,” is one that has been lost today and, given its evident importance, needs to be regained: an inquiry into the being of life, into what it means to be alive. This inquiry is in turn determinative for Aristotle’s conception of being as such.¹ As seen in the SS1921 seminar, Heidegger takes very seriously Aristotle’s claim at the start of De Anima that “the knowledge (γνῶσις) of the soul appears to contribute things of great importance toward all truth (πρὸς ἀλήθειαν ἅπασαν)” (402a4–6).

• The being of life is for Aristotle to be identified with a peculiar and unique kind of motion: one that preserves rather than alters or destroys what is moved. One of Heidegger’s most important discoveries in the SS1921 seminar is a type of becoming in which what becomes, rather than departing from itself, comes to itself. The crucial point he sees is that if living is a kind of motion, it is one radically different from the kind of alteration and becoming nonliving things undergo.

• Aristotle’s Physics has essentially nothing to do with what is called physics today because its goal is to understand the being of motion without which one cannot understand the nature of anything that exists by nature. The goal of Aristotle’s physics, in other words, is not to calculate the movement of inert masses for which movement is purely external, but to understand movement as something intrinsic to the being of everything that exists by nature. If Heidegger insists that Aristotle’s Physics is a work of ontology, it is again, as in the case of De Anima, to suggest that we have an inquiry here that is lost today, in this case falling outside of the modern opposition between physics and metaphysics. Jan Patočka’s important study on Aristotle (2011) can be seen as further developing this Heideggerian reading of the Physics and further emphasizing the contrast with modern physics.² He is, for example, very clearly following in Heidegger’s footsteps when he claims that “Aristotelian philosophy can therefore truly be understood as a philosophy of movement. Aristotle’s great philosophical intuition is ontological movement” (412). He explains the contrast with modern physics in noting that Aristotle’s goal is not to master and control movement, but to understand its nature and explain it; this is why he has no interest in what is the sole concern of modern physics: the “mathematization” of movement.³ The book by Heidegger’s student from the 1920s, Walter Bröcker, is also motivated by “the conviction that the question of movement is the fundamental question of philosophy” (1987, 5). Bröcker even writes that “the riddle of movement is the life’s breath of Aristotelian philosophy” (44) and that “movement is the fundamental problem of Aristotelian philosophy” (62). What Heidegger has thus made possible is finding in Aristotle’s Physics an ontology that has as its object both the being of movement and the movement of being.

• Being in the sense of the categories, and thus being in the sense of ousia as the primary category to which all the others refer, is only one sense of being from which one must distinguish, and to which one must not reduce, being in the sense of truth and being in the sense of dunamis and energeia/entelecheia. We have also seen Heidegger recognize in the seminars that, among these senses, it is the latter sense that is the primary sense, that, in brief, entelecheia, even more than ousia, is Aristotle’s fundamental ontological concept.

• This fundamental ontological concept is only obstructed by its later interpretation as “act” and “actuality.” Along the same lines, Heidegger recognizes that the notion of praxis is not limited for Aristotle to expressing these or those actions that we may or may not do, but says something about the very character of our being. If the unpublished seminars reveal Heidegger’s own difficulties with these fundamental concepts of praxis, energeia, and entelecheia, they encourage us to follow Heidegger in attempting to think these concepts anew, freed from the later conceptual encrustations that have completely obscured their original sense.

• The complementary concept of dunamis is also of central ontological importance. For Aristotle, to be is to be-capable-of. This is why every being, whatever it is specifically, whether a knife or a human being, has its being defined by a distinctive function (ergon) and why the activity in which it fully realizes its being must be understood as en-ergeia.

• Aristotle’s definition of time as “the number of motion with respect to before and after” is far from exhausting what his texts have to tell us about the nature of time.⁴ Aristotle recognizes the distinctive temporality of what is neither always nor for the most part, that is, the “coincidental,” and therefore is capable of understanding time in opposition to “eternity.” Furthermore, Aristotle’s central ontological notion of energeia is characterized by a temporality distinct from that of motion and captured by what Heidegger calls in the SS1928 seminar “the peculiar perfect” of having seen in still seeing and still seeing in having seen. Finally, the hama that forms an essential part of the fundamental principle of non-contradiction expresses a temporality of human existence that must be distinguished from simply “being-in-time.” In these ways Heidegger’s seminars show (even against his own statements in other texts) that a study of time in Aristotle cannot and should not confine itself to his explicit definition of the time that characterizes the beings of nature.

• We misrepresent Aristotle’s ethics if, interpreting it from the perspective of modern subjectivity, we take it to be only about aims and values. Instead, Aristotle’s ethics is quite explicitly based on an interpretation of what it means to be human (see the “function” argument of NE I.7) and the “good” itself, as expressing the completeness of what has realized the tendency inherent in its being, is an ontological concept. Happiness is not a mere aim or goal, but that in which we human beings truly become what or rather who we are.

In at least these ways, Heidegger’s seminars on Aristotle require us, as they required his students, to read Aristotle again from the beginning, questioning and challenging traditional assumptions that have arguably blocked our access to what is most thought-provoking and philosophically rewarding in his texts.⁵ Indeed, one can summarize the positive contribution of Heidegger’s seminars in the way that Gadamer and others who experienced them first-hand did: they make Aristotle speak to us and challenge us as if he were a contemporary, though free of contemporary prejudices and assumptions. On the other hand, the seminars also dispel a common but erroneous assumption: that such a philosophically productive reading of Aristotle must do interpretative violence to his texts.⁶ Because the seminars considered here involve such close readings of Aristotle’s texts, they show us that such an approach can on the contrary exhibit utmost faithfulness to the text, making us see what is actually there in all its strangeness, unseen by supposedly more “objective,” historical-philological readings that are blinded by philosophical assumptions that, far from lacking, they simply leave unacknowledged and unquestioned. This is not to deny that Heidegger sometimes misreads a text and is guilty of hermeneutical violence. But let the interpreter of Aristotle who claims never to be guilty of such a thing cast the first stone.

II. How the seminars are challenged by Aristotle’s text

In thus defending the positive contribution the seminars make to our understanding of Aristotle, we must avoid falling into the error of thinking that Heidegger’s readings cannot and should not be criticized.⁷ If Heidegger appropriates Aristotle’s thought for his own philosophical aims, he still claims in the seminars to be interpreting Aristotle, not some product of his imagination, and he is focused on an understanding of Aristotle’s own words (even engaging in textual criticism when there is a question of what these words actually are). Heidegger’s readings therefore can and should be critically evaluated as readings of Aristotle; we should note where they fail or at least encounter serious limitations. Indeed, the seminars arguably contribute as much to our understanding of Aristotle when they fail as when they succeed. Here again I will simply summarize some of the limitations we have already noted in our analysis of the seminars.

• Heidegger only hints at the ontology of life suggested by De Anima. He quickly turns away from De Anima in focusing on human existence and never returns to it, not even when he later, in the 1929/30 Fundamental Concepts of Metaphysics course, tries to make up for the lack of an analysis of non-human life in Being and Time. Therefore, while he could be considered as ahead of his time in claiming already in 1921 that the “biological” perspective was the determinative one for Aristotle’s physics (and therefore for his ontology on Heidegger’s reading), he cannot himself be credited with what has come to be called the “biological turn” in the study of Aristotle.⁸

• That the focus of Heidegger’s reading shifts from De Anima to the Physics means that what is distinctive about the motion that characterizes living things as distinct from non-living natural things receives no further attention. Heidegger arguably does try of find this distinctive motion in the concepts of energeia and entelecheia, and the notion of “absolute motion” in the 1928 seminar can also be seen as an interpretation of it. But these notions are no longer identified with life as such but become appropriated for human Dasein.

• Heidegger’s treatment of the Physics as Aristotle’s central ontological text has the effect of ignoring Aristotle’s own insistence that it is not “first philosophy.”⁹ This insistence is important because it means that neither an understanding of being as being nor an understanding of the highest being is to be found in the Physics. Heidegger of course is aware that this is Aristotle’s view, but he himself insists on interpreting Aristotle’s “first philosophy” from the perspective of his physics rather than the other way around. After, for example, rejecting in the SS1921 seminar Natorp’s view that chapters 7–9 on becoming do not belong with the rest of Metaphysics Z, Heidegger can be seen as going to the other extreme in treating them as the central and most important chapters. There is for Heidegger ultimately no difference between the study of kinêsis and the study of ousia.

• If Heidegger recognizes senses of being in Aristotle beyond that according to the categories and even gives priority to being in the sense of dunamis and energeia/entelecheia, we have also seen in the seminars a conflicting tendency to reduce Aristotle’s conception of being to ousia, and even more narrowly to the hupokeimenon, all in service of the overarching and unwavering thesis that the Greeks understood being as presence.¹⁰

• We have seen that Heidegger never does justice to Aristotle’s sharp distinction between energeia and kinêsis. His tendency instead is to treat energeia as simply a form of kinêsis (a “complete kinesis”), thus making kinêsis the central ontological concept. It might not seem to make an important difference whether one treats energeia as a perfect, complete kinêsis or treats kinêsis as an imperfect energeia. But it arguably makes a great difference, and while Aristotle’s view is explicitly the latter, Heidegger’s is clearly the former.¹¹ We have seen the same thing occur with Aristotle’s parallel and equally sharp distinction between praxis and poiêsis. Heidegger continually ignores and even negates this distinction, insisting on treating praxis as a kind of poiêsis, with the result that the latter becomes the fundamental ontological concept. This is what allows Heidegger to maintain that Aristotle interprets being as “being-produced.” Yet here too one could argue that praxis is the central concept of Aristotle’s ontology and that poiêsis is understood as simply a deficient praxis. Here the crucial text, as we have seen, is the latter half of Metaphysics IX.6, where Aristotle sharply distinguishes praxis and energeia from kinêsis and in a context in which the former, not the latter, are the fundamental ontological concepts. As we have also seen, while Heidegger deals with this text much more in the unpublished than in the published seminars, even there he mostly circles around it without ever providing a detailed and comprehensive interpretation. It is for this reason that Heidegger’s reading is also incapable of coming to terms with the “unmoved mover,” that is, with a living activity that is unmoved and excludes dunamis.¹²

• Heidegger’s reading can also be criticized for not respecting Aristotle’s distinction between phusis and poiêsis, assimilating the former to the latter and treating the latter as the primary phenomenon. That Aristotle repeatedly uses examples drawn from the realm of human “craft” (τέχνη) can be explained by the heuristic value of such examples and does not require us to conclude that Aristotle’s understanding of natural phenomena is drawn from them. To employ a principle often enunciated by Aristotle, that technê is what is better known to us does not imply that it comes first in the things themselves. On the contrary, one could easily make the case that Aristotle draws his fundamental ontological concepts, such as dunamis and energeia, from natural phenomena, and specifically the phenomenon of life, rather than from human production.¹³ The fundamental perspective, in other words, is biological, as Heidegger himself sees in SS1921 but quickly loses sight of.

• The lack of a sufficiently detailed reading of Metaphysics IX also prevents Heidegger from explaining how the ontological sense of dunamis relates to the other senses (or even deciding, as we have seen, where the distinction falls within Metaphysics IX itself). His habit of continuing to translate as “possibility” and “being-possible” may be a result of this. Also, if in practice he ends up not so much reversing the priority of energeia over dunamis in Aristotle as subordinating both to kinêsis, he does not defend such a move in any detail.¹⁴ This is presumably why he returns to Metaphysics IX during the 1930s, but there, as we will see, ignoring most of the book for a focus on the first three chapters.

• One of the most peculiar features of Heidegger’s reading of Aristotle is that, while it points to different senses of temporality in Aristotle, it does not pursue a detailed examination and discussion of any of them. The seminar on Physics II does not go much beyond asserting that Aristotle’s insight into temporality in the chapters on luck and chance was not equaled until Bergson. The seminar of SS1928 ends by noting the “peculiar perfect” that characterizes energeia as something requiring further thought. The WS1928/29 seminar postpones discussion of the hama in Aristotle’s formulation of the principle of non-contradiction and never returns to it. It is as if Heidegger’s reading of Aristotle reaches its limit with the question of time. There is in any case material here for many doctoral dissertations!

• If Heidegger retrieves the ontological dimension of Aristotle’s ethics, he does so at the price of neglecting altogether its determinate ethical content. This does not appear to be simply a matter of Heidegger never having had the time to address this ethical content. There is arguably a very un-Aristotelian opposition between the ontological and the ontical, the existential and the ethical, in Heidegger’s thought that prevents him from addressing this dimension of Aristotle.¹⁵ Indicative is his continued insistence that telos means “end” in the sense of “completion” and not “aim,” as if it could not mean both. If the highest good is that in the attainment of which we become fully what or who we are, it is also something we seek and aim at by acting in determinate ways. The same can be said of “politics”: while an ontological category to the extent that it expresses our being as a being-with-one-other, it also must discuss and, yes, evaluate different possible concrete ways of being with one another. It is one thing to note the ontological foundations of ethics and politics in Aristotle; it is another to “ontologize” ethics and politics, to act as if they are worthy of thought only as ontology, or to refuse to consider anything but their ontological dimensions. If ethics and metaphysics are arguably much more closely connected in Aristotle than they tend to be today (after all, the highest object of his metaphysics, that is, the divine thinking on thinking, is also the model for the good life), Aristotle insists on keeping them distinct as fields of inquiry with their own methodologies and standards of success. When one considers the diversity of fields of inquiry in Aristotle, and even within first philosophy itself the diversity of senses of being, there is something terribly reductive about Heidegger’s reading.

III. What the seminars have to teach us about Heidegger

As the last point already suggests, limitations in Heidegger’s reading of Aristotle can also expose limitations in his own thought because of how Heidegger develops his own thought in constant dialogue with Aristotle. Therefore, the seminars can teach us as much about Heidegger as about Aristotle and, most importantly, encourage a critical reading of Heidegger.¹⁶ Let us first summarize the positive things we learn from the seminars about Heidegger’s own path.

• Arriving at an understanding of being that could be adequate to the being of life was a central motivation for Heidegger at the outset. It explains why the first Aristotelian text he turned to in his teaching was De Anima.

• The analysis of Dasein’s being as a being-possible is an appropriation and reinterpretation of the notion of dunamis, especially in the central role it plays in De Anima. When Heidegger claims in the SS1921 seminar that there is a notion of the “I” in Aristotle and that it is to be found in the concept of dunamis, he is foreshadowing his own analysis of the “self” of Dasein several years later.

• In line with the preceding point, Aristotle’s interpretation of the being of motion was of decisive importance for Heidegger’s analysis of the being of Dasein.¹⁷ Furthermore, the notion of energeia as “complete” motion was of decisive importance in Heidegger’s arrival at a conception of Dasein as “absolute motion.” In seeking a conception of being distinct from “being-present” that could do justice to our own way of being, Heidegger sought and found in Aristotle what he himself calls at one point a “pan-dynamism of being in general” (GA22, 170).

• The focus on productive activity (the context of the workshop, the example of the hammer, the central category of equipmentality) in Being and Time’s analysis of Dasein’s everyday being-in-the-world can be traced back to a reading of Aristotle that takes poiêsis rather than praxis as paradigmatic for the interpretation of our being.¹⁸ If “care” is an interpretation and appropriation of praxis, Heidegger does not follow Aristotle in sharply distinguishing it from poiêsis, at least not in our everyday being-in-the-world and being-with-one-another.¹⁹

• Heidegger’s ontological investigations were directed against a world-ontology, that is, an ontology that derives its conception of being from things encountered within the world and then transfers this conception to what does not have the character of a worldly object, in other words, human Dasein and the divine. While Heidegger saw such a world-ontology as ultimately going back to Aristotle, he also found in Aristotle the resources for overcoming it.

• If key concepts of Aristotle’s ethics become key existentials in Being and Time, this is through the filter of a “Lutherian,” or at least Christian, reinterpretation.²⁰ The key example is the famous interpretation of phronêsis as “Gewissen.” This is part of the very project just mentioned of overcoming a supposedly Greek world-ontology as handed down to us through medieval Scholasticism, a project that in two of the seminars presented here explicitly appeals to the Protestant reformation.

• Heidegger’s reflections on the temporality of Dasein were not simply a “destruction” of Aristotle’s analysis of time, but were inspired by Aristotle’s own insights into forms of temporality distinct from that of physical objects in motion. One could claim that what Heidegger in 1928 calls the “peculiar perfect” of praxis/energeia becomes authentic temporality in Being and Time²¹ and that Aristotle’s insight into the temporality of what is neither always nor for the most part in Physics II inspires the notion of the “Augenblick.”²² Heidegger can therefore, after Being and Time, find the temporality of Dasein in the hama that he sees as playing a key role in the principle of non-contradiction. The seminars, in short, show that Heidegger learned much more about time from Aristotle than his “destruction” of Aristotle’s definition of time in the Physics would suggest.

IV. Where the seminars express possible limitations and challenges to Heidegger’s own path of thinking

If we are interested in more than the history of philosophy, if, that is, we are interested in more than the development of Heidegger’s thought and the influences on it, if we seek to think with and beyond Heidegger, then the seminars prove invaluable in exposing possible limitations in Heidegger’s thought.

• The first and obvious one is Heidegger’s failure to develop the ontology of life that first drew him to Aristotle.²³ The closest he comes to this is in the 1929/30 course on The Basic Concepts of Metaphysics. But even there Heidegger acknowledges that his account of the organism is incomplete; what is lacking is nothing less than an account of the peculiar motion or motility (Bewegtheit) that characterizes life (GA29/30, 385–387).²⁴ One of the students we have seen present throughout these seminars of the 1920s was apparently sufficiently inspired by the problem of an ontology of life to pursue such an ontology himself. I am referring, of course, to Hans Jonas and his well-known study The Phenomenon of Life: Toward a Philosophical Biology (2001). The following claim can be read both as inspired by Heidegger’s seminars and as challenging Heidegger: “Thus the organic body signifies the latent crisis of every known ontology and the criterion of ‘any future one which will be able to come forth as a science’” (19).²⁵

• The only alternative to an ontology of presence Heidegger found in Aristotle is one that interprets the being of Dasein as a being-possible, a motion complete in its incompleteness, having no other “end” but “death.”²⁶ If Aristotle’s notion of activity can be equated neither with static presence nor with motion, it arguably represents a possible conception of being that Heidegger never acknowledged.²⁷ As we will also see in the later seminars, Heidegger tries to get beyond thinking of being as motion (Bewegung) by thinking of it instead as Bewegtheit, but the latter term obviously does not get beyond the perspective of motion.²⁸ In other words, Heidegger’s struggles with Aristotle’s texts in the seminars show theses texts to resist both a conception of being as presence and a “pan-dynamism of being” and to point to an understanding of being as “activity” that can be neither identified with motion nor understood from the perspective of motion.²⁹

• There is a certain obliteration of the notion of praxis in Heidegger’s thought. One can indeed see a radicalization of the notion of praxis in Heidegger’s account of Dasein’s authenticity, of its existing for the sake of itself. But if there is thus a version of the distinction between poiêsis and praxis in Heidegger’s thought, it is not, as it is in Aristotle, a distinction between production and activity.³⁰ The seminars indeed have shown Heidegger repeatedly passing over the distinction as it is made in Aristotle’s texts.

• Finally, much has been said about the absence of an ethics in Heidegger and his reading of Aristotle only draws more attention to this absence. What is said above in critique of Heidegger’s reduction of Aristotle’s ethics and politics to ontology applies to the parallel reduction in his own thought.

V. Heidegger’s later return to Aristotle: an endless challenge of interpretation and appropriation

1. The return to Metaphysics IX and Physics II in the 1930s

During the 1930s, in another seminar and in an essay, which counts as his first publication on Aristotle, Heidegger returned to some of the same texts he interpreted at length in the seminars of the 1920s. His reading, however, evolved in some significant ways that can be only indicated here.

If in the 1924/25 seminar Heidegger saw chapter 6 and its distinction between kinêsis and energeia as the turning point of Metaphysics IX and read the earlier chapters back through this chapter, in the SS1931 course Vom Wesen und Wirklichkeit der Kraft (GA33) Heidegger interprets the entire book through the first three chapters and thus from the perspective of dunamis and energeia “with respect to motion” (κατὰ κίνησιν). While he acknowledges that Aristotle’s aim is to move toward an understanding of dunamis and energeia that goes beyond their being spoken “with respect to motion” (1046a1–2; ἐπὶ πλέον), he insists, to the point of inventing Greek not in the text, that even this broader, ontological understanding is still “κατὰ κινήσεως,” that is, still an understanding within the perspective of motion (53).³¹ That motion should thus become the dominant perspective may be due to the interpretation of Dasein a few years earlier in the SS1928 course as absolute motion. In any case, the central chapter 6 with which we have seen Heidegger struggle in the seminars of the 1920s, rightly recognizing in it the linchpin of the account of being in the sense of dunamis and energeia and indeed the introduction of the ontological conception of these terms, simply drops out of his reading. If his reading does not get beyond the first three chapters of Book IX, it is not for lack of time, but with the conviction that everything essential is found there: if motion is the perspective within which dunamis and energeia even in the ontological sense must be understood, then their analysis relative to motion in the first three chapters already unlocks this broader understanding.³² Furthermore, one thing the neglect of chapter 6 makes possible is reading into the text, and into the concept of entelecheia/energeia in particular, a very reductive conception of being as presence-at-hand, so that Aristotle’s debate with the Megarians is said to concern the problem of how dunamis can be present-at-hand (see 170–171).

The reading of Physics II in the essay “Vom Wesen und Begriff der Φύσις: Aristoteles, Physik B, 1 (1939)” confines itself to chapter 1 of Book II. This essay follows the earlier seminars in claiming that “meta-physics is in a completely essential sense ‘physics’, that is, a knowledge of φύσις (ἐπιστήμη φυσική)” (WB, 311) and that “The Aristotelian ‘Physics’ is the hidden and therefore never adequately thought-through fundamental book of Western philosophy” (312). While therefore again taking being-moved (Bewegtsein) to be the “fundamental way of being” (Grundweise des Seins), Heidegger now affirms that this is not to identify being with motion (Bewegung), calling such an identification an “unGreek thought” and even an “unphilosophical one” (314). Yet Heidegger’s objection to this identification appears to be only that it identifies being with motion in an ontic sense; the whole thrust of his interpretation is to identify being with motion in an ontological sense, that is, what he calls “being-moved.” Thus, he translates morphê, the primary sense of both phusis and ousia, not as “Aussehen” (look), but as “Gestellung in das Aussehen” (setting into the look), a translation that allows him to characterize morphê itself as kinêsis (346, 357) as long as this term is translated as “Bewegtheit” rather than “Bewegung.” If Heidegger in this essay claims entelecheia to be “the fundamental word” (Grundwort) of Aristotle’s thought (352), this word, along with energeia, itself appears to be identified with Bewegtheit, which Heidegger distinguishes from Bewegung as “the essence from out of which motion and rest determine themselves [das Wesen, aus dem sich Bewegung und Ruhe bestimmen]” (354). While avoiding here any detailed interpretation of Metaphysics Θ.6 where Aristotle sharply distinguishes energeia from kinêsis, Heidegger cites the phrase used there to characterize the temporality of energeia, “simultaneously sees and has seen” (1048b23; ὁρᾳ ἅμα καὶ ἑώρακε), and interprets as follows: “The motion of looking around oneself and looking after is genuinely for the first time highest being-moved in the rest [Ruhigkeit] of (simple) seeing gathered within itself [Die Bewegung des Sichumsehens und Nachsehens ist eigentlich erst höchste Bewegtheit in der Ruhigkeit des in sich gesammelten (einfachen) Sehens]” (354). He can thus characterize entelecheia as “the essence of being-moved (that is, the being of what is moved)” (356), indeed as “the essence of κίνησις” (357). Finally, as already noted in chapter six, Heidegger in this essay, while still characterizing phusis as a “Sich-Herstellen,” insists that “Herstellen” is not “Machen” (359) and thereby seeks to do justice to the distinction between phusis and technê in a way that he failed to do in his earlier reading.³³ This modification or clarification still occurs, however, within the assumption that the Greeks understood being as presence, even if this understanding itself is now “verbalized” as a “presencing” in what is unconcealed (see 340) contrasted with “mere presence-at-hand” (342; die bloße Vorhandenheit).

2. Heidegger’s return to Aristotle toward the end of the war and after the teaching ban in a series of seminars on the Physics and Metaphysics in 1944 and 1950/52³⁴

In SS1944, Heidegger gave a seminar focusing on the first three chapters of Metaphysics Γ. While Heidegger here describes the principle of non-contradiction as the center of Book Γ and the most puzzling in Western philosophy (394–395), he never gets to it in the seminar, as he does in that of 1928/29. His reading of the initial chapters is intent on showing the ambiguity of the phrase “being insofar as being” (ὄν ᾗ ὄν) between the nominal and the verbal senses of the participle, as well as between the meaning of “beings in general” and the meaning of “what most corresponds to the concept of being” (the highest being). The goal is to demonstrate the origin of metaphysics in the failure to think the difference between beings and being and thus the failure to raise the question of being. The seminar then turns to the initial chapters of Book Z, noting there again the ambiguity in the question “what is ousia” between “what things count as ousia” and “what is ousia itself.” As in earlier seminars, Heidegger’s attempt to reconcile his thesis that being is understood as presence with Aristotle’s rejection of the identification of ousia with the hupokeimenon yields no clear results. In general, the seminar seems an attempt to bring the Aristotelian texts discussed earlier in line with the narrative of a “history of metaphysics” Heidegger had developed since the 1930s.

After both the war and the lifting of the teaching ban, Heidegger teaches a seminar in WS1950/51 titled “On Causality.” This seminar, like that on the fundamental principles and the problem of categories in 1928/29, brings Kant and Aristotle together. It begins with reflection on the “transcendental” in Kant as an inquiry into the possibility of objects and thus, Heidegger insists, as an inquiry into the objecthood of objects, into the being of beings: ontology, not epistemology. Kant’s transcendental is an interpretation of Aristotle’s “being insofar as being” (481; ὄν ᾗ ὄν). Turning again to Physics II, Heidegger finds there the insight that “motion belongs to presencing itself [zum Anwesen selbst de Bewegung gehört]” (484). This is what allows him to affirm once again that the Physics is “the grounding text of Western metaphysics [das Grundbuch der abendländischen Metaphysik]” (477). Here again Heidegger can be seen as suppressing the distinction between physics and first philosophy as well as Aristotle’s qualification that perhaps even of the things that exist “by nature” (φύσει) only some are in movement (185a12–13; ἢ πάντα ἢ ἔνια). When Heidegger addresses this qualification in the present seminar (probably forced to do so by the participants),³⁵ he claims that if things not in motion are being alluded to here, they can only be things at rest, where rest can be understood only from the perspective of motion. Therefore, he maintains that “the ἔνια contains no limitation of the ontological generality of the proposition” (489). This ontological universality of motion is also affirmed when Heidegger, in a kind of repetition of the 1928 seminar, dismisses as “a crazy thing” Kant’s claim that motion does not belong to the a priori, but can be known only through experience: “Factically, motion is constantly present in the Critique of Pure Reason and the individual categories cannot be thought at all without motion, but significantly Kant did not actually see this” (491). Turning to Aristotle’s account of motion, Heidegger notes that the Greek understanding of motion was fundamentally different from the modern (493) and again insists that “things being moved” (κινούμενα) is an ontological predicate. Nature is not the ontic cause of some particular motion, but the cause of motion as such (500). When he turns to the four causes, Heidegger claims again, as he did in 1923/24, that they are all won from poiêsis, but now with the important qualification introduced in the 1939 essay: “Ποίησις not as ‘making’ in the sense of fabricating [Anfertigen], but in the completely broad sense of ‘bringing forth’” (502).

The following summer, SS1951, Heidegger gave another seminar on Aristotle, this one on Physics B.1, Γ.1–3, thus returning to texts already studied often in preceding seminars. As we see, the central importance of the Physics for Heidegger persists from the 1920s to the 1950s and here in 1951 he again characterizes this text as “the watershed in the fluvial land of Western thinking” (206). But we also have here a repetition of the central thesis of the 1924/25 seminar on medieval ontology when Heidegger immediately adds that therefore “the whole of Western philosophy is in a certain sense a ‘naturalism’” and that this has hindered the meditation on the essence of history, not to mention theology. We also see repeated here the old thesis that Aristotle interprets phusis and praxis (human Dasein) from the perspective of poiêsis, but Heidegger again adds, as he has been since 1939, that poiêsis is to be understood broadly as “Herstellung” in the sense of “bringing-forth” (Hervorbringung). Heidegger also appears to want to identify phusis with ousia, so as to conclude from the characterization of the beings that are by nature (φύσει ὄντα) as all (Aristotle’s qualification “or some” is again ignored) being in motion, that what needs to be shown is “to what extent being-in-motion [In-Bewegung-Sein] is being in the genuine sense” (529). It is the paradox (for the Greek mind) of motion belonging to presence (Anwesenheit) that leads Aristotle, according to Heidegger, to the question of how beings (ὄντα) are to be understood if they are in movement (κινούμενα): a question that results in the decisive step of interpreting being as energeia (534).

Arguably the most important moment in this seminar, as representing at least a significant shift from the interpretation of the 1920s, though one we have seen already underway since the 1939 essay, is Heidegger’s clarification, presumably in response to a misunderstanding on the part of the participants, that he is not suggesting that Aristotle understood ousia as kinêsis or kinêsis as ousia (541–542). Aristotle identifies ousia instead with energeia, Heidegger explains, and the essence of the latter is “the ἔργον which has nothing to do with motion and power” (542). Heidegger even goes so far as to describe energeia as “a static concept [ein statischer Begriff]” (542). This goes very much against the tendency we have seen in the seminars of the 1920s to “dynamize” the notion of energeia and weaken or even deny its difference from kinêsis.³⁶ Yet this change might be in service of the thesis already defended in the 1920s, namely, that the Greeks understood being as “being-present-at-hand.” Thus, when Heidegger turns to the four senses of being in Aristotle (which, he notes, is a problem never discussed as such in Aristotle’s surviving texts), he interprets both being in the sense of the categories and “accidental” being as presupposing an understanding of the hupokeimenon (549), concluding, “Again the same fundamental understanding of being lies at the basis” (549). Heidegger then repeats the surprising thesis we found in the seminar of 1924/25 on medieval ontology: as he there claimed that the Greeks identified the ousia of the stool with its simply being finished at hand (fertig vorhanden) and that they considered its use for sitting as something outside of its ousia and therefore “accidental,” so here he claims that on the basis of their understanding of being the Greeks could see the standing-in-shadow of the house as only inessential, whereas on a different understanding of the house as thing rather than as “product” (Hergestelltes), whether it stands in shadow or not would not be a matter of indifference (549–550). But Heidegger goes even further, suggesting that also the other two senses of being presuppose an understanding of being as hupokeimenon: what is in dunamis and energeia are the “beings in motion” (ὄντα κινούμενα) that are in and of the hupokeimenon; being as being-true or unconcealed belongs to what lies before in its lying before. Heidegger makes the aim of his reading fully explicit: “I seek only to get you to see that in all four ways [of being] the ὑποκείμενον remains determinative” (550). Heidegger’s position here appears much more extreme than it is in any of the 1920s seminars. Even when he notes that phusis has the character of aitia or cause, Heidegger concludes that it has this character as “what lies before” (551; ὑποκεῖσθαι).³⁷ All of Aristotle’s senses of being are reduced to this “static” sense of what “lies before” and thus is present-at-hand.

In the following semester of WS1951/52, Heidegger pursues his reading of Physics Γ but also turns his attention to Metaphysics Θ.10.³⁸ Heidegger again clarifies that he does not wish to interpret ousia as kinêsis, but rather to see it precisely as ousia with a view to kinêsis (558). In other words—and this is the crucial point—motion remains Heidegger’s horizon for the interpretation of ousia. Ernst Tugendhat significantly interrupts the protocol at this point to ask an important question that can also be asked of Heidegger’s reading in the 1920s: if the principle of motion is the perspective from which natural things and artefacts are distinguished, how can it be taken to be an essential determination of natural things only? (559). There is an attempt at an answer in the following class: phusis, Heidegger suggests, is still being understood in its original broad meaning as identical with being (εἶναι), even as it is restricted to a particular region of beings (562). Here we have a problem that has always dogged Heidegger’s reading of the Physics: how can he read it as an interpretation of being (and thus as a work of ontology) while acknowledging that Aristotle restricts it to a particular region of beings? Heidegger’s following reading of Physics Γ focuses on Aristotle’s appeal to being in the sense of the categories and being in the sense of dunamis and energeia in his account of motion. Heidegger does not, however, discuss the latter notions through a reading of Aristotle’s texts, but rather indirectly by way of Descartes and Kant, with the following justification: “Now, we are no longer Greeks, that is, we can carry out their thinking only in contrast to our own way of thinking. It is therefore necessary first to secure these questions for ourselves from our perspective” (575; also 585, 632, and 636). Yet in turning to Metaphysics Θ.10, Heidegger claims that an understanding of its relation to chapters 1–9 is obstructed by the modern interpretation of dunamis and energeia as possibility (Möglichkeit) and reality (Wirklichkeit) and of alêtheia as the truth of a proposition (594–595). While Heidegger again avoids any discussion of the argument of Metaphysics Θ as a whole, he makes clear how he understands the key terms at issue there. He assumes again a static interpretation of both energeia as being-in-the-end (Im-Ende-Sein), being-in-the-work (Im-Werke-Sein), and of entelecheia as “the pure presence of something completed in itself and so persisting in itself” (595; die reine Anwesenheit eines in sich Vollendeten und so in sich Bestehenden). Heidegger believes that this interpretation explains why chapter 10, which addresses being in the sense of truth, is to be found in Book Θ, which is as a whole dedicated to being in the sense of dunamis and energeia: that which is present [das Anwesende] can “presence” (an-wesen), that is, can be in energeia and entelecheia as Heidegger interprets these terms, only in an open or undisclosed region: the “un-hidden” (ἀ-ληθές).³⁹ What little attention there is to Aristotle’s account of energeia in Metaphysics Θ consists of making much of the identification of energeia with “the obtaining of the thing” (τὸ ὑπάρχειν τὸ πρᾶγμα), or, as Heidegger would have it, the being-present-at-hand of a thing (1048a26–32). The determination to reduce all senses of being to being in the sense of hupokeimenon is once again evident. Indeed, Heidegger ends the seminar with a static account of motion itself. Motion is characterized as what is at any given moment (jeweilig) present between a coming and going (605). Strangely (or not), the account of Physics Γ here contains no detailed discussion of Aristotle’s actual definition of motion in this book; Heidegger does cite it at one point, but only to state that this purely conceptual understanding is no understanding at all (636); and according to one protocol, his allusion to the definition only emphasizes motion’s “being completed” as entelecheia.⁴⁰ In accordance with this characterization of motion, Heidegger insists that Aristotle identifies time with the “now”: “Therefore the ‘was’ and the ‘will be’ do not belong to time. Χρόνος [time] means νῦν [now]” (648). A little later he clarifies the sense of time here as “the present time [die gegenwärtige Zeit],” “time in the sense of whiling from . . . to . . . [die Zeit im Sinn des Währenden von . . . bis . . .]” (649). What then of that “peculiar perfect” of “sees and simultaneously has seen”? What of the “dynamic” time of that which, being neither always nor for the most part, just “happens”? The account of Aristotle’s conception of time appears here as reductive as the account of his conception of being.

This is the last of Heidegger’s seminars devoted to Aristotle, at least that we currently have or are aware of. Given what the present book owes to the seminar transcripts written and/or preserved by Helene Weiss during the 1920s, it is fitting to note that in this last Aristotle seminar of WS1951/52 Heidegger recommends the Aristotle book of his former student as “the only book that provides something proper [Ordentliches] regarding the Physics of Aristotle and perhaps Aristotle in general” (609). Weiss is thus involved with Heidegger’s reading of Aristotle from beginning to end. Yet what Heidegger owed his student is hardly compensated by the rather condescending compliment that she provided something “Ordentliches.” Weiss was certainly capable of doing more than replicating neatly the teaching of the master: we have seen her challenge Heidegger in her own notes on the 1928/29 seminar and she published a number of articles that, if showing the influence of Heidegger, also go beyond him in the topics they address. Unfortunately, Weiss did not have the opportunity to go further as she died at around the same time that Heidegger was recommending her book. Was this a coincidence or had Heidegger heard of her death and intended his comment as a memorial?

The goal of the present chapter is to suggest ways in which we ourselves might question Heidegger’s reading, both as a reading of Aristotle and as an expression of his own thought, and thereby make it philosophically fruitful. Though I have also indicated what we can learn from the unpublished seminars, we should let them more provoke than teach us. We are not in the position of students imbibing the words of the master, but in the position of inheritors coming to terms with what has been bequeathed to us.

That we should question Heidegger’s reading is, I believe, what Heidegger himself would expect. Despite the seemingly dogmatic statements and reductive interpretations found in the last seminars as in earlier ones, Heidegger recognizes that even in Metaphysics Θ the fundamental concepts of dunamis and energeia “remain questionable [fragwürdig] for Aristotle.” And far from claiming to know better, Heidegger at one point, faced with the task of interpreting Physics 200b26ff., where Aristotle introduces being in the sense of dunamis and entelecheia with the end of defining motion, observes, “We are in poor shape here [armselig]. We are supposed to treat of a matter we do not at all understand. Or do you understand what ἐντελέχεια means? I don’t” (617). It is in precisely this spirit that we should ourselves study both Aristotle and Heidegger’s seminars. The fact that even the later seminars briefly addressed here, far from being conclusive, respond to Aristotle’s texts with fundamental questions that are left open shows that Heidegger’s Auseinandersetzung with Aristotle was never finished, even after a total of around sixteen courses and seminars (depending on how one counts them) over the span of three decades dedicated wholly or mostly to the interpretation of Aristotle’s texts. I hope this book has shown that it is in our interest to continue this Auseinandersetzung, not only for the better understanding of both Aristotle and Heidegger it makes possible, but also for a better understanding of our own philosophical task today.