The (Other) Meaning of Life: Aristotle on being animate

Transcription

1 The (Other) Meaning of Life: Aristotle on being animate by Rich Cameron Department of Philosophy University of Colorado, Boulder Boulder, Colorado

2 Despite evolutionary biology's success explaining the genesis and constitution of living things, neither biology nor contemporary philosophy of biology has provided an adequate account of being animate. Quotation one on the handout adequately represents the contemporary state of the art concerning the nature of life: there is no agreed upon definition, and there is disagreement even over whether we ought to be seeking a definition. The reason usually given for thinking that life cannot be defined, that living things are materially continuous with nonliving things, need not keep us from offering a substantive definition of life. Just as we can define being bald despite the fact that this state is materially continuous with being hairy, life's material continuity with nonlife poses no insuperable barrier to an adequate definition of life. Further, there is substantive reason to be dissatisfied with contemporary naturalistic accounts of the life's nature. Representative here is Paul Churchland's definition (quotation two on the handout). x is alive = df x is a "semiclosed physical system that exploits the order it already possesses and the energy flux through it, in such a way as to maintain and/ or increase its internal order." 1 Churchland notes that on this definition, beehives, termite colonies, cities, the biosphere and candle flames are all living things. Despite these 1 Churchland (1988, 173). 1

3 counterintuitive consequences, however, Churchland endorses the definition as an adequate theoretical definition of life. 2 Problematically, however, the only reasons Churchland (or anyone else) gives for rejecting the more ambitious task of seeking a definition that is consistent with both our scientifically informed intuitions about life and contemporary evolutionary biology are (a) the continuity of life with nonlife and (b) history of failure at the more ambitious project. Neither of these is decisive, however; the first has already been dealt with, and the second may mean nothing more than that we need to keep looking. My goal in this paper is to provide an adequate, fully naturalistic account of the nature of life, an account that is consistent with both evolutionary biology and our scientifically informed intuitions concerning what it is to be alive. Perhaps surprisingly, the account I endorse is (for the most part) Aristotle's. This paper will, therefore, be devoted mainly to an exegesis of Aristotle's account of the nature of life. Defense of the account that results, and, in particular, defense of the claim that it meets the criteria of adequacy listed on the handout, will be deferred to the question period. 1 Locating Aristotle's account in the de Anima After his typical review of previous views on the soul in book i of the de Anima, Aristotle begins a 'fresh start' in book ii, moving quickly to provide a 2 Those who engage in the project of giving 'theoretical' definitions generally distinguish their task from that of 'conceptual analysis.' Conceptual analysis, on this view, seeks to capture the content of our concepts; theoretical definition seeks to reflect how things are in the world. There is no necessary tension between these two projects however; our concepts may (we hope) 2

4 number of definitions of the soul, each of which employs core concepts from his developed metaphysics. The soul must be a substance in the sense of the form of a natural body having life potentially within it. But substance is actuality, and thus soul is the actuality of a body as above characterized (DA ii.1 412a20; see also 412a27, 412b3, 412b10; ii.2 414a28; PA i.1 641a25-9; GA ii.4 738b27; Met. vii b14-31, vii a5, viii a35) Aristotle believes that he has given a satisfactory general definition, but moves on in de Anima ii.2 to investigate the matter from the point of view of what is more observable to us in order to make clear the cause of his definition (DA ii.2 413a11-20). From this point of view, it turns out that the soul is the starting point of (archê) and is defined by (horistai) powers that the soul has (DA ii.2 413b11-13). These powers are specified with reference to the fact that the soul is the cause of life. We resume our inquiry from a fresh starting-point by calling attention to the fact that what has soul in it differs from what has not in that the former displays life. Now this word has more than one sense, and provided any one alone of these is found in a thing we say that thing is living viz. thinking or perception or local movement and rest, or movement in the sense of nutrition, decay and growth. (DA ii.2 413a21-5) One might suppose that Aristotle here offers a "cluster" definition 3 of life such that: adequately reflect the state of things. For different naturalistic takes on this distinction, see Millikan (1989) and Neander (1991). 3 "Cluster" definitions of life are quite common in the contemporary literature. Mary Ann Warren (1997) expresses the idea behind such definitions well: "It should not surprise us that there is no single (or multiple) necessary and sufficient condition for the proper application of the ordinary concept of life... Basic practical concepts, such as that of life, develop through many generations of experience. Consequently, such concepts often lack the clarity and simplicity that are desirable in, for instance, mathematical or scientific theories... the complexity and the unclear boundaries of many of our ordinary concepts cannot readily be defined away, except that the cost of substituting a different concept for the original one" (26). Further, "I think it best to stay with a definition similar to Webster's, i.e. one that lists 3

5 x is alive = df x has at least one of the following powers: (a) thinking; (b) perception; (c) local movement and rest; (d) the movement of nutrition, growth, and decay. One problem 4 with attributing such a definition to Aristotle is that Aristotle does not typically offer disjunctive lists as definitions; his standard form of definition involves specification of genus and differentia. Further, such a definition would inherit the main problem associated faced by any cluster definition, the problem of the unity of the definition: Why are these powers on the list and others not? What do these abilities have in common that makes them, individually or in groups, sufficient for life? If we can answer the question, it appears that that answer ought to be our definition of life. If we cannot answer it, it would appear that the original cluster of properties provides little more than a set of heuristically useful correlates to being alive. We might try to find unity in Aristotle's cluster of properties through the insight that Aristotle believes that the powers of the soul are arranged hierarchically. The power of nutrition, Aristotle held, can be had without sensation or thought (as in plants), but the powers of thought and sensation cannot be had (at least in biological organisms) without the power of nutrition. 5 Perhaps, then, the original list of properties jumbles together some marks of life (sensation, thought, local movement) while the definition of life is in terms characteristic features that can serve as criteria of life, but that does not attempt to resolve in advance all possible uncertainties about what ought to count as a living thing" (30). 4 In what follows I am covering ground which is already well covered by Matthews (1992) and Shields (1999); I make no claims for originality in this portion of my brief introduction to Aristotle's account of life. 5 See DA 413a32-4, 413b4-13, 414a29-415a12; PN 454a11-454a18, 474b

6 of one member of the original list: the power of nutrition. As Aristotle says, "By life we mean self-nutrition and growth and decay" (DA ii.1 412a14). 6 Such a definition would appear to solve our problems by giving unity to our original cluster: having the nutritive soul explains a thing's being alive, but sense perception thought and local movement are marks or signs of life that are in some way connected to this power. This definition appears to fail as well, however, for two reasons. The first reason is that such a definition may be circular. After all, we need to discriminate between the taking on of nutrition that living things do and that done by an ordinary household sponge (when wiping up, say, spilt milk), but it is difficult to see how to do this without simply referring to the fact that the kind of taking in nutrition we have in mind is that which living things do. Further, Aristotle himself seems to define the nutritive power in terms of the capacity to absorb food (DA ii.4 416a20-1), but he also defines food in terms of its relation to the soul (DA ii.4 416b10-13; cf. GA 335a15-6). A problematic circularity, then, haunts this type of definition. Because the proposed Aristotelian definition in terms of the nutritive soul is at risk of circularity, we may hope that Aristotle does not endorse it. We have a strong reason to believe that he doesn't, thankfully, since Aristotle is unabashed in supposing god to be alive in virtue of god's possession of nous, but Aristotle's god is nonbiological and possesses no nutritive soul (Met. xii b26-30; see also OH a8; NE b20). Our intuitions about 6 See also 413b1-2, 415a24-5; PN 479a28-9; GA 741a1. 5

7 living, like Aristotle's, seem to allow that it is possible for there to be nonbiological life, and Aristotle's account acknowledges this possibility (as an actuality). This result seems only to increase our difficulties, however. For now we need to find some unity not merely within the list of biological powers Aristotle refers to in de Anima ii.2 413a21-5, but between those powers and whatever it is in virtue of which a being like God would be alive. Aristotle's account of life, if it is to be satisfactory in its own terms must apparently be 'weak' enough to avoid the circularity problem but 'strong' or 'rich' enough to meet conditions of adequacy concerning the unity of definitions that account not only for the actual but also the possible diversity of life. The problems we have thus far surveyed for 'simple solutions' to the problem of locating Aristotle's account of life are indicative of problems contemporary accounts suffer. Problems surrounding the unity and diversity of life and problems concerning the counterintuitive consequences of proposed definitions are extremely common. From this perspective, it is unsurprising that the 'simple' answers that suggest themselves in Aristotle's texts fail as definitions of life, and it is fortunate that Aristotle appears not to endorse such views. As we might expect, we must look more deeply if we are to discover either Aristotle's account or an adequate contemporary account of life. I turn now to discuss perhaps the most widely known interpretation of Aristotle on the nature of life, that of Gareth Matthews' "de Anima and the 6

8 Meaning of Life". 7 I argue that Matthews' core insight is correct, but that his account fails as he has developed it. In the final section of the paper, I offer my positive development of the core insight. 2 Matthews on the Meaning of Life Matthews' interpretation of Aristotle on life takes its central motivation from reflection on the possibility of god's life. If the only (possible) living things were biological organisms, it might be plausible for us to give an account of life in terms of self-nutrition, the most basic and widely shared psychic function. 8 The problem created by (the possibility of) god's life is so drastic, however, that following Aristotle's methodological practice Matthews turns to "try a very different approach" (190). 9 Matthews' new beginning starts from the insight that Aristotelian organisms "naturally act so as to preserve their species" (190, citing DA a27-b2 text one on your handout). From this insight Matthews develops his account around the notion of a 'psychic' or species preserving power, a notion which is then employed in a definition of what it is to be alive. x is a psychic power =df there is a species s, such that, for x to be preserved, individual organisms that belong to s must, in general, exercise x (191). x is a psychic power for species s =df for s to be preserved individual organisms that belong to s must, in general, exercise x (191). 7 Matthews (1992). 8 Of course we would have to get over the circularity problem to make this solution work. Can we give a non-circular, informative, scientifically adequate definition of the power to take on nutrition which includes all and only living things (i.e. includes plants and animals but excludes (household) sponges)? Aristotle scholars would have the additional task of explaining away Aristotle's apparent commitment to the homonymy of life as well. 9 Unless otherwise specified, all page numbers in this section are from Matthews (1992). 7

9 x is alive =df there is a species s, and a psychic power p, such that x belongs to s, p is a psychic power for species s, and x can exercise p (191). Less formally, Matthews explains, "what it means to say that an organism is alive is that it can exercise at least one psychic power; that is, at least one of the powers that organisms of its species must, in general, be able to exercise for the species to survive" (191). Matthews believes that this account of life is Aristotle's, and that it avoids and solves a number of problems. It is claimed to avoid circularity, to solve the problem of explaining the special role nutrition plays in Aristotle's statements about life, and to make room for god's (nonbiological) life. Matthews believes that his account explains both why self-nutrition plays such a central role in Aristotle's discussions of life and explains a scholarly puzzle concerning why Aristotle claims that life is 'said in many ways' (DA ii.2 413a21, Top. vi a27). Among mortal living things the most basic species-preserving power is self-nutrition, and this accounts for its special place in Aristotle's account of life. "Still, what exactly having species-preserving, or psychic, powers amounts to varies from species to species. And in this way something like [the homonymy of life] is also true" (193). 10 Finally, Matthews believes that his account can handle (the possibility of) god's life despite the seemingly insuperable problem that his account is framed 10 I do not believe that Matthews solution to this scholarly puzzle is adequate given the richness of Aristotle's concept of homonymous definition. Elsewhere I defend a solution to this puzzle which locates a kind of homonymous definition in Aristotle similar to the determinable/determinate relation. Roughly, then, I claim that the correct solution to this problem is to view life (in Aristotle's eyes) as a determinable with different determinate ways of being alive satisfied by different orders of living things. Full exegesis and textual defense of these claims is beyond the scope of this paper, however. 8

10 in terms of the possession of species preserving powers and that Aristotle's god belongs to no species. "To preserve their species," according to Matthews, nonmortal beings such as god "need only preserve their existence by continuing to engage in whatever activity is essentially theirs" (193). Thus, Matthews offers us a gloss on his account that shows that and how it applies even in the case of a living and nonbiological god. 3 Two objections to Matthews' account In this section I offer two criticisms of Matthews' interpretation and diagnose the interpretation's failure. On my reading, Matthews' account suffers in that it is both too weak and too strong. My diagnosis of the problem is that Matthews' account goes wrong in straying from its motivating insight that living things act to preserve their species (contained in DA 415a27-b2 again text one on the handout). The solution to these problems is to respect Aristotle's intent in this passage more faithfully. To begin, recall that the central concept in Matthews' account of life is the concept of a psychic power. Here is his definition again: x is a psychic power for species s =df for s to be preserved individual organisms that belong to s must, in general, exercise x (191). The first problem for Matthews' account is that on his definition it turns out that the heart's ability to make thumping noises is a psychic power of creatures with hearts. 11 For creatures with hearts to be preserved it must in general be the case that their hearts exercise the power to make thumping noises (this is 11 See DA iii.9 432a-32b4. 9

11 true because when hearts perform their function, circulating blood, they inevitably make thumping noises). If too many hearts cease to exercise the power to make thumping noises, the species will not be preserved. But surely the heart's ability to make thumping noises is not a psychic power it is instead an accidental concomitant of a psychic power. The example I've just given is framed in modern terms 12 that foreshadow my approach to this problem's solution. It is important to note, however, that despite the modern trappings of my example, Aristotle clearly draws the same distinction in his own terms. Thus, with Aristotle we must distinguish between the definitory powers of the nutritive soul and the inevitable concomitants of those powers (such as the production of useless residues and eventual death and disintegration 13 ). The Aristotelian credentials of this distinction are safe. Thus, generalizing from this case, my first conclusion is that Matthews' account fails because it cannot distinguish psychic powers (i.e. pumping blood, the activity of the nutritive soul) from the accidental concomitants of psychic powers (i.e. producing thumping noises, producing useless residues). Another, related, failure may be illustrated with a different example. I begin by noting that in order to save his definition from circularity Matthews must intend us to understand 'organism' in the definition not to mean 'biological entity' but to mean, more generally, 'thing.' 12 I believe the example originates with Carl Hempel. 13 See PA iv.2 677a12-31, cf. GA i. 725a4-6. See also Phys. ii.2 194a30-3, OH ii.6 288b15-18, Met. vi b8-10, PN 465a14-5; PA 670a30. 10

12 x is a psychic power for species s =df for s to be preserved individual organisms [i.e. things] that belong to s must, in general, exercise x (191). Once we see this, we can see immediately that the account is far too liberal. In order for sounds to preserve themselves in echo chambers they must, in general, exercise their power to bounce off of walls. In order for radioactive isotopes to remain the isotopes they are, they must decay at a given rate (when the cease to do this, they have become a different isotope). 14 Examples, may be multiplied indefinitely, but generalizing from these cases we may note that for any continuing subject there will be some list of powers such that subjects of that kind must exercise those powers to continue in existence. Further, any such power may play the role of a 'psychic power' in Matthews' account of life. Matthews' account of life is too liberal, I conclude, since its central concept (if understood in a non-circular fashion) applies to all continuing subjects and not simply to living things. If Matthews' account isn't circular, then it is far too broad. 15 As confirmation that this problem genuinely arises for Matthews' account, note that the fault I've just illustrated explains Matthews' own extension of his account to cover god's life. The prima facie problem Matthews' account faced in god's case was that while god is alive, it is the member of no species while Matthews' account is framed in terms of species preserving powers. How does Matthews solve the problem? By extending his account along exactly the lines 14 I owe this example to Robert Pasnau. 15 It may be objected that none of the counterexamples I raise truly 'exercises' the powers I've listed. The problem with this attempted solution, however, is that it appears to reintroduce the 11

13 marked out in my second line of criticism. He takes it that god is alive just in case god exercises powers necessary for it to remain in existence. But this condition is not satisfied uniquely by god. Instead, as I argued in the previous paragraph, it will be satisfied by any continuing subject whether that subject is alive of not. I conclude that something has gone terribly wrong with Matthews' account. To summarize, the account is too weak in two ways. First, it fails to distinguish between psychic powers and the accidental concomitants of psychic powers. Second, on one interpretation it falls into the circularity problem (if 'organism' is understood to restrict the account to biological organisms). Further, the account is too strong. If we read the account such that it avoids the circularity problem (if 'organism' in the definition is understood to mean nothing more than 'thing'), then the account is far too liberal since on this reading all continuing subjects have the 'psychic powers' definitive of life. My diagnosis of these problems is that Matthews lost the thread of his motivating insight very early on. Matthews took his start from Aristotle's comment that (again, text one on the handout):... for any living thing that has reached its normal development and which is unmutilated, and whose mode of generation is not spontaneous, the most natural act is the production of another like itself, an animal producing an animal, a plant a plant, in order that [hina], as far as its nature allows, it may partake in the eternal and divine. That is the goal towards which all things strive, that for the sake of which [ekeinou heneka] they do whatsoever their nature renders possible [hosa prattei kata phusin]. (415a27-b2) problem of circularity into the account. Which things 'exercise' powers in the appropriate way, after all? Living things. I owe this objection to comments by C. Shields. 12

14 In this passage Aristotle asserts the teleological character of life. The most natural act for any living thing is its action for the sake of participation in the eternal and divine. 16 However, Matthews loses sight of this fact early on in his analysis as is clear from the fact that his analysis contains no teleological concepts or elements. Instead, teleology is analyzed out of Matthews' account in favor of necessary conditions. A sufficient condition for being alive, on Matthews' account, is the possession of a capacity to exercise one on a list of powers which are jointly necessary for kind preservation. 17 Nothing in Matthews' account specifies that the power possessed must be exercised for the sake of kind preservation. This fact explains the account's failure to distinguish psychic powers (the exercise of the nutritive soul) from accidental concomitants of psychic powers (the production of resides or death). The problem that besets Matthews' account in this regard is well known in the literature on biological teleology (i.e., the problem of distinguishing functions from the accidental concomitants of functions Hempel first raised the problem), and its solution is considered by contemporary philosophers of biology a necessary condition on the adequacy of an account of teleology. In addition, the elimination of teleological 16 It is important to note that this commitment to teleology is not as extravagant as it may sound. Aristotle makes clear elsewhere that this comes to no more than the claim that organisms have reproductive ends. See Politics i a I have switched from Matthews' loaded language of preserving species of 'organisms' to speaking more generally of 'kind preservation' to avoid problems associated with unconsciously limiting our attention in evaluating the definition to the kind we are trying to define: living things. 13

15 elements from Matthews' final account also explains why it is possible to extend the account to non-teleological entities which are plainly not alive such as sounds and radioactive isotopes. Such entities (indeed any continuing subject) will 'exercise' powers necessary for their preservation; none will do so for the sake of their preservation. 4 Aristotle on being animate I claim that we avoid the problems that afflict Matthews' account by taking the teleological aspect of de Anima ii.4 much more seriously. I argue that Aristotle defines life in terms of the possession of teleological directedness, and (further) that this definition of life satisfies the criteria of adequacy listed on the handout. Below I will briefly defend the claim that the definition provides the correct interpretation of Aristotle on being alive, leaving the question of whether the account satisfies the criteria of adequacy for discussion. In what follows, I argue first that Aristotle holds life and teleology to be coextensive. I then argue for the stronger thesis that Aristotle defines life teleologically. Finally, I conclude by noting that Aristotle explicitly draws the distinction necessary to head off the most obvious sorts of counterexamples to the original definition. Aristotle held that being teleologically directed is necessary and sufficient for being alive. That being alive is sufficient for teleological directedness is made clear in Aristotle's treatment of the movements of the heavens. In Aristotle's view, once we recognize the heavens to be living beings we must recognize that despite their uniform shape they have functional distinctions which set off their 'right' and 'left' sides (OH ii.2 285a28-31). Further, being 14

16 alive is, in the same context, treated as a necessary condition for being teleologically directed. We can understand the movements of the heavens to be goal directed only if we recognize them as being alive (OH ii a19-292b24). As additional support for the coextensiveness of life and teleology in Aristotle, note Aristotle's claims that we cannot suppose something to have nonteleological desire (orechis) (DA iii a15), 18 but that it is also impossible to conceive of anything with such an orechis not to be alive (EE i a27): orechis is teleological, and sufficient for life. 19 Further evidence comes from the fact that health and disease are coextensive with living (PN 436a18, Rhet. i a30), and these are teleological concepts (HA x.1 633b16-20, and Rhet. i b3-6 with NE ii a15-7 and EE ii a38). Further, we must understand a thing to be alive in order to understand it as having a good of its own (NE viii b30; see also GA ii.5 741a19, Phys. ii.6 197b7). These considerations yield strong positive reason to suppose that Aristotle considered life and teleology to be coextensive It is important to note that Aristotle frequently uses mentalistic sounding terms such as 'desire' to describe processes which he finds to occur in beings which have, on his view, no minds. The teleological use of 'desire' is broader than its use as a psychological notion used in explaining behavior mentalistically. 19 The references, quoted above, from DA ii.4 415a27-b2, b15-20 and MA 6 700b15-6 all constitute additional support for the claim that life is sufficient for teleological directedness. 20 The argument in the main text contains only the positive textual case for believing that Aristotle defined life teleologically; it does not directly respond to arguments to the effect that the scope of teleology is much broader. I argue elsewhere that the most promising interpretations on which Aristotle's teleological commitments extend beyond living things fail. 21 The necessity claim may be doubted given that artifacts possess ends but are not alive; I deal with this objection below. 15

17 Evidence that Aristotle endorses the stronger claim that life is defined teleologically comes from the application of a principle of kind individuation to the case of life. Aristotle commits himself to a metaphysical principle of kind individuation that we may call 22 the functional determination thesis. This view is paradigmatically stated in the following passage (text three on your handout): What a thing is is always defined by its function ((h)apanta d' estin (h)ôrismena tô(i) ergô(i)): a thing really is itself when it can perform its function. (Meteor. iv a10-11) 23 This principle would, if applicable to the case at hand, resolve the issue of whether life was defined by or merely associated with teleological commitment. We may, then, ask whether Aristotle applied this metaphysical principle to the case of living beings. It is clear that he does. As evidence, I cite Aristotle's broadly attested commitment to the claim that living beings' last state (in the normative sense, not merely in the sense that the last point in a series is an end see Met. v b24-9) is their nature, form, and end. Thus, [T]he end is developed last ((h)ustaton gar ginetai to telos), and the peculiar character of the species is the end of the generation in each individual. (GA ii.3 736b3-4. See also Phys. ii.7 198b5-9; IA 2 704b15-6, 8 708a10; Met. v b20; Phys. vii.3 246a10-15) Further, Aristotle applies this thesis to the lives of plants, animals, and men in the famous function argument in Nichomachean Ethics i.7. [I]n general, for all things that have a function (ergon ti) or activity (praxis), the good and the 'well' is thought to reside in the function, so would it seem to be for man, if he has a function.... What then can this be? Life (to zên) seems to be common even to plants, but we are seeking what is peculiar to man. Let us exclude, therefore, the life of nutrition and growth. Next there would be a life of perception, but it also seems to be common 22 Following Shields (1999). 23 See also EE iii b23; OH ii a8, ii b21-2; Pol. i a23; DA ii.4 416b23. 16

18 even to the horse, the ox, and every animal. There remains, then, an active life of the element that has a rational principle. (NE i b26-7, 1097b a4) Life is here identified as a function common to all living things. Specific functions for particular types of living things are specified by reference to the most complete activities of beings of the same type. As a final support for this definitional thesis we may note that Aristotle identifies the life of a living thing with its essence. That it [i.e., the soul] is substance (ousia) is clear; for in everything the substance ((h)ê ousia) is identical with the cause of its being (to aition tou einai), and here, in the case of living things, their being is to live (to de zên... to einai estin), and of their being and their living the soul in them is the cause or source. (DA ii.4 415b12-4) The essence of a living creature is its life, and it is the essence that we specify in the definition of a thing. 24 This is identified with the final cause of living beings at de Anima ii.4 415b15-20 and Generation of Animals i.1 715a4-8. I conclude, then, that Aristotle defines being alive in terms of the possession of teleological directedness. The core notion of being animate, then, can be expressed in the following definition. (D4 on your handout). x is alive =df x possesses teleological directedness. This account captures the core insight appealed to in Matthews' account of life, but avoids the problems associated with his account by explicitly emphasizing the teleological character of life. No reductive strategy is here employed on Aristotle's notion of teleology, as I believe is appropriate to Aristotle's own views. Whatever we initially think about the plausibility of sui generis teleology from a modern naturalistic standpoint, this robust and nonreductive definition 24 See APo. ii.10 93b29-30; Top. i.4 101b20-2, i.5 101b31, i.8 103b9-10, vii.3 153a15-22, vii.5 154a31; Met. viii a

19 of life avoids the problems associated with reductive accounts and sets us on the right track, I claim, for a fully acceptable account of life. (See again the criteria of adequacy on your handout.) Nevertheless, the account as developed thus far is open to obvious counterexamples, for artifacts have purposes but are not alive. Such counterexamples can be overcome, however if Aristotle distinguishes between possessing ends intrinsically (as living things do) and having them derivatively (as artifacts do). I will now argue that Aristotle does draw this distinction. The distinction between intrinsic and derived ends appears in the following extended passage. (This is text 7 on your handout.) But the prior (to proteron) is already [said] in many ways. [E.g.] [i] that for the sake of which a thing is and [ii] the thing which is for its sake are different and the latter [, ii,] is prior in coming to be, but the former [, i,] prior in being (ousia(i)). Further, that which is for the sake of an end has two divisions, first, [ii'] that whence motion is, and second [ii''] that which is used by that for the sake of which. I mean, first, [ii'] something that generates, and second, [ii''] the organ or tool used for the thing generated.... So there are three things: first, [i] the end or that for the sake of which; second, [ii'] the things for the end the source of motion and generation (for what is productive or generative is, as itself, relative to (pros) what it makes or generates); third, [ii''] the useful or those which the end uses. Thus, first some part which contains the source of motion [ii'] must come to be..., next after this the whole and end [i] [comes to be], and third and last the organic parts serving this [i.e., the end] for certain uses [ii'']. (GA ii.6 742a21-36, with omission. My translation, following Peck) This passage claims that both the generative principle, [ii'], and the organs of living beings, [ii''], are posterior in being to the being or form that is the end of generation and whose ends regulate the activity of the organs. Now, the being of an organ is determined by its function, by what it is for (GA i.2 716a23-5). Generation of Animals ii.6, then, states that organs derive their being ( = their ends) from the form; the teleology of organs is derived teleology. The teleological function that defines the organs and generative principle is 18

20 posterior in being, that is, that it derives its end from the prior ends of the mature form. This commitment is confirmed by Aristotle's well known claim that the body and its parts exist for the sake of the soul (DA ii.1 415b17-18, PA i.5 645b15-20, PA i.1 642a12-4; see GA ii b21-2), but that the soul does not likewise exist for the sake of the body (see PA iv b14). The body's parts, defined functionally (GA i.2 716a23-5), are defined in terms of their contribution to the intrinsic well-being of the whole whose ends they serve. But, as we saw in Generation of Animals ii.6 (text seven), the whole is prior in being to the parts and does not derive its ends or goods from any prior ends. This distinction between intrinsic and derived ends is further confirmed by Aristotle's well known commitment to the claim that body parts such as eyes and hands are only homonymously (or equivocally) 'eyes' or 'hands' once the organism of which they are parts has died: the parts are defined by their functions, and their function depends for its existence on the life of the organism to which they belong. 25 I claim, then, that we have Aristotelian license to draw the distinction necessary to adequately handle the problem artifactual ends pose for the original Aristotelian definition of life in terms of the possession of teleological directedness. Aristotle holds that certain things with purposes derive the being or essence of their ends from the being or essence from other, nonderivative ends. Thus, D5 on your handout, 19

21 x is alive = df x possesses intrinsic teleological directedness. expresses Aristotle's notion of what it is to be alive. This account of life in terms of the possession of intrinsic teleological directedness solves the interpretive problems any such account must solve. It avoids the problem of circularity, it provides unity to the diversity of marks of life, it accounts for god's life (for god has ends, see NE i a15 & Met. ii.1 993b21), and it accounts for Aristotle's contention that different things live in different ways (this is so, roughly, since the ends of different kinds of living things will be different). I conclude, therefore, that this is indeed Aristotle's account of life. I hold, more strongly, that this account of life satisfies the criteria of adequacy listed on your handout, but the full argument for that stronger philosophical thesis is beyond the scope of the present paper. Thank you. 25 See Meteor. iv a10-15; DA i.1 412b17-24; Pol. i a20-5; PA i.1 640b30-641a6; GA ii.1 734b25-7; Int a

22 Bibliography Churchland, Paul M Matter and Consciousness. Revised Edition ed. Cambridge: A Bradford Book: The MIT Press. Matthews, Gareth B De Anima and the Meaning of Life. In Essays on Aristotle's De Anima, edited by M. C. N. A. O. Rorty. New York: Oxford University Press. pp Reprinted in Boden, Margaret A., ed The Philosophy of Artificial Life. New York: Oxford University Press. pp Millikan, Ruth G In Defense of Proper Functions. Philosophy of Science 56: Reprinted in Allen, Colin, Marc Bekoff, and George Lauder, eds Nature's Purposes: Analyses of Function and Design in Biology: The MIT Press. pp Neander, Karen Functions as Selected Effects: The Conceptual Analyst's Defence. Philosophy of Science 58: Reprinted in Allen, Colin, Marc Bekoff, and George Lauder, eds Nature's Purposes: Analyses of Function and Design in Biology: The MIT Press. Shields, Christopher Order in Multiplicity: Homonymy in the Philosophy of Aristotle. Oxford: Clarendon Press. Warren, Mary Anne Moral Status: Obligations to Persons and Other Living Things. Oxford: Clarendon Press. 21