Consider the notion of “purpose.” Coyne seems to think that all talk of purpose entails a conscious rational agent like us, but that is, conceptually speaking, just sloppy. Where purpose is concerned -- a better term would be “teleology” or (better still because unassociated with irrelevant pop-theology baggage) the Scholastic’s term “finality” -- there are, as I have pointed out many times (e.g. here), at least five kinds, with each of the last four progressively more unlike the sort we know from introspection. Hence we can distinguish:What are we to make of this? Can the single concept 'purpose', 'teleology', or 'finality' span such a vast range of phenomena described in (1) to (5)? I struggle with this. As, in a way, does Feser. For as we move from (1) to (5) the concept seems to come under increasing stress, as evidenced by the frequency of the quotation marks. One question I'd like to ask is this. If everything has purpose(s), how do purposes interact? Is my 1-purpose in going to the fridge somehow a sum or composition of the 5-purposes of my molecules? Is this panpsychism? This query is analogous to the query directed to the Aristotelian theory of forms: How, if at all, is the form of a thing related to the forms of its parts? Again, it would seem that we should say that the 5-purposes of molecules are trivially satisfied. They are never thwarted. But my 1-purpose in going to the fridge is easily thwarted. How does it come about that some purposes can be thwarted? Then again, perhaps the 5-purposes of molecules can be thwarted. Maybe what happens in nature is the outcome of an argy-bargy of competing purposes among the molecules. Perhaps a theory of composition for purposes could answer this question?
1. The sorts of purposes we know from our own plans and actions. In this case the end that is pursued is conceptualized. When you order a steak, you conceptualize it as steak (as opposed, say, to vegetable protein processed to look and taste like steak), you express this concept linguistically by using the word “steak,” and so forth.
2. The sorts of purposes non-rational animals exhibit. A dog, for example, exhibits a kind of purpose or goal-directedness when it excitedly makes its way over to the steak you’ve dropped on the floor. Such a purpose is certainly conscious -- the dog will see the meat and imagine the appearance and taste of past bits of meat it has had, and it will also feel an urge to eat the meat -- but it is not conceptualized. The dog doesn’t think of the meat as meat (as opposed to as textured vegetable protein), it doesn’t describe it using an abstract term like “meat,” etc.
3. The sorts of “purposes” plants exhibit. A plant will grow “toward” the light, roots will “seek” water, an acorn “points to” the oak into which it will grow, etc. These “purposes” are not only not conceptualized, but they are totally unconscious. A plant will not only not think of the water it “seeks” as water (as a human being would), but it will not feel thirst or anything else as it “seeks” it (as an animal would).
4. The “goal-directedness” of complex inorganic processes. David Oderberg offers the water cycle and the rock cycle as examples of a kind of inorganic “goal-directedness” insofar as there is an objective (rather than merely interest-relative) fact of the matter about whether certain occurrences are parts of these causal processes. For instance, the formation of magma may both cause certain local birds to migrate and lead to the formation of igneous rock, but causing birds to migrate is no part of the rock cycle while the formation of igneous rock is part of it. That each stage of the process “points” to certain further stages in a way it does not “point” to other things it may incidentally cause reflects an extremely rudimentary sort of teleology. It is a kind of teleology or “directedness” that involves neither conceptualization of the end sought (as human purposes do), nor conscious awareness of the end (as animal purposes do), nor the flourishing of a living system (as the “purposes” of plants do).
5. Finally there is a kind of absolute bare minimum of “directedness” exhibited in even the simplest inorganic causal regularities. As Aquinas argued, if A regularly generates some specific effect or range of effects B (rather than C, or D, or no effect at all), there is no way to make this intelligible unless we suppose that A is inherently “directed toward” or “points to” the generation of B (rather than to C, or D, or no effect at all). Suppose all higher level causal regularities -- not only the water and rock cycles, but even simpler phenomena like the way the phosphorus in the head of a match generates flame and heat when the match is truck, or the way ice cools down room-temperature water surrounding it -- were entirely reducible to causation at the micro-structural level. Still, we would have absolutely basic causal regularities -- the fact that some micro-structural phenomenon A regularly generates a range of outcomes B -- that is intelligible only if we suppose that A inherently points to B. Or so the traditional Aristotelian view goes, anyway. Here we lack in A not only conceptualization, consciousness, and life, but also complexity of the sort in view in teleology of Type 4. There is just the bare “pointing to” or “directedness toward” B which would exist even if the causal transaction were not part of some larger structure.
Let me say that I accept entirely Ed's 1-purposes, though I don't appreciate the emphasis he is making in his paragraph (1) above. I would want to say that a purpose P in performing action A is a reason for A, in the sense that one believes that in some context C, P follows from A. A suggestive notation might be C,A ⊢ P. A purpose P for an object O is a reason for its existence: C, ∃O ⊢ P, in an abuse of notation. There is much that needs to be clarified here. We are clearly in the realm of the rational planning of our actions in order to achieve our ends. The key idea is the notion of logical sufficiency. Also, that a purpose is a cognitive entity, a thought, something that can participate in an inference, rather than a spatio-temporal entity or property. It's difficult to see how to extend this idea to other domains. I think Ed's 2, 3, 4, and 5-purposes must be metaphorical usages, and the metaphor is increasingly stretched as we go down the list. I suggest that the sense of directedness or of finality that Ed finds is the sense in which the premises of an inference lead to its conclusion. The spatial metaphors here are striking. Let's consider his example of a match. Suppose we have internalised our experience of matches into a general proposition: striking a match produces a flame. So producing a flame might be our purpose or our end in striking a match. Without any further explanatory resources at our disposal we might be tempted to account for the regularity expressed by the general proposition by means of a purpose or end or directedness towards producing a flame that is inherent in striking a match. This might be seen as a vestige of animism. The difficulties with it are immediately apparent. Is the directedness inherent in the match or in its striking? As I understand it, the Aristotelian view is that these 'qualities' are inherent in the objects. Certainly, causation is seen as a relation between objects. How then does the striking come into it? The problem is that the resources available in a explanation of this kind---ordinary objects, or even ordinary objects equipped with directednesses---are too coarse-grained. A nice demonstration of this is Ed's ice-cube example. Granted that the ice-cube at minus five degrees Celsius, say, will cool liquid water at twenty degrees. But it will also warm liquid CO2, say, at minus sixty Celsius.
For as I have also pointed out many times (e.g., once again, here) there are several possible views one could take about purported teleology or finality of any or all of the five sorts just described:My view is closest to (E). 1-purposes exist, though they are cognitive entities. 2, 3, 4, and 5-purposes do not.
A. One could hold that one or more of the kinds of teleology described above really do exist but that it is in no way inherent in the natural world, but rather imposed on it from outside by God in something like the way the purposes of an artifact are imposed on natural materials by us. Just as the metal bits that make up a watch in no way have any time-telling function inherent in them but derive it entirely from the watchmaker and users of the watch, so too is the world utterly devoid of teleology except insofar as God imparts purposes to it. This “extrinsic” view of teleology is essentially the view represented by William Paley’s “design argument.”
B. One could hold instead that teleology of one or more of the kinds described above really does exist and is inherent in the natural world rather than in any way imposed from outside. Someone who takes this view might hold (for example) that an acorn really does have an inherent and irreducible “directedness” toward becoming an oak, or that in general efficient causes really are inherently “directed toward” or “point to” their effects, and that this just follows from their natures rather than from any external, divine directing activity. Why does an acorn “point toward” becoming an oak? Not, on this view, because God so directs it, but just because that is part of what it is to be an acorn. This ”intrinsic” view of teleology is the one usually attributed to Aristotle (who, though he affirmed the existence of a divine Unmoved Mover, did not do so on teleological grounds, as least as usually interpreted).
C. One could hold that teleology of one or more of the kinds described above really does exist and has its proximal ground in the natures of things but its distal ground in divine directing activity. On this view (to stick with the acorn example -- an example nothing rides on, by the way, but is just an illustration) the acorn “points to” becoming an oak by its very nature, and this nature is something that can be known whether or not one affirms the existence of God. To that extent this view agrees with View B. But a complete explanation of things and their natures would, on this View C, require recourse to a divine sustaining cause. This is the view represented by Aquinas’s Fifth Way, which (as I have noted many times) has nothing whatsoever to do either with Paley’s feeble “design argument” or with the arguments of recent “Intelligent Design” theorists. (I have expounded and defended Aquinas’s Fifth Way in several places, such as in my book Aquinas and in greatest detail in a recent Nova et Vetera article.)
D. One could hold that one or more of the kinds of teleology described above are in some sense real but only insofar as they are entirely reducible to non-teleological phenomena. To speak of something’s “pointing to” or being “directed toward” some end is on this view “really” just a shorthand for some description that makes no reference whatsoever to teleology or finality.
E. Finally, one could hold that none of the sorts of teleology described above exists in any sense, not even when understood in a reductionist way. They are entirely illusory.
1. Now that means that of the approaches to teleology or finality described above, the materialist is committed to either View D or View E. But View D really collapses into View E. For attempts to reduce teleological notions to non-teleological notions are notoriously problematic. To take a stock example, suppose it is claimed that such-and-such a neural structure in frogs serves the function or purpose of allowing them to catch flies (insofar as it underlies frogs’ behavior of snapping their tongues at flies). And suppose it is claimed that this teleological description can be translated without remainder into a description that makes use of no teleological notions. For instance, it might be held that to say that the neural structure in question serves that function is just shorthand for saying that it causes frogs to snap their tongues at flies; or perhaps that it is shorthand for saying that the structure was hardwired into frogs by natural selection because it caused them to snap their tongues at flies. The trouble is that the same neural structure will cause a frog to snap its tongue at lots of other things too -- at BB’s, black spots projected onto a screen, etc. -- yet it would be false to say that the function of the structure in question is the disjunctive one of getting frogs to eat either flies or BBs or spots on a screen, etc. Of course, someone might respond: “But that’s because the reason the neural structure gets frogs to snap their tongues, and the reason it was favored by natural selection, was in order to get them to eat flies, not to eat BB’s or spots on a screen!” But that’s just the point. To say that “the reason” the structure exists is “in order to” get frogs to do that, specifically, is to bring teleological notions back into the analysis, when the whole point was to get rid of them.Ed is being a little careless here. The underlined sentence conflates two reasons:
a. Why the neural structure gets frogs to snap their tongues, andThe explanation for (a) is in terms of the physiology of frogs---how the neural structure processes retinal images of small dark objects and stimulates the muscles of the tongue. The explanation for (b) is the usual Darwinian one---the differential reproduction of frogs equipped with such neural structures and refinements thereof, compared to those without. One can explain this without resort to 'in order to'. I'm afraid Ed is putting up an all-to-familiar anti-Darwinian straw-man.
b. Why the neural structure was favoured by evolution.
2. This sort of problem -- known by philosophers as the “disjunction problem” -- illustrates the impossibility of trying to reduce teleological descriptions to non-teleological ones. Such purported reductions invariably either simply fail to capture the teleological notions, or they smuggle them in again through the back door and thus don’t really reduce them after all. Hence, as naturalists as otherwise different as John Searle and Alex Rosenberg have acknowledged, a consistent materialist has at the end of the day to deny that teleology really exists at all. That is to say, he has to opt for what I have labeled View E.I fail to see the relevance of the disjunction problem. This is supposed to show that there can be no unique function or purpose for a physiological structure. Under my interpretation of 'purpose' this is obvious. One would not expect there to be a unique P such that C,∃O ⊢ P. But this has no impact at all on the Darwinian argument. Among the things in the frog's environment that trigger tongue snapping are flies, and the benefits of snapping at nutritious flies outweigh, in terms of reproductive success, the downsides of snapping at possibly-noxious fly-like things. This account need not mention functions or purposes. Isn't Jerry Fodor's attack on Darwinism just this misapplication of the disjunction problem? Ed has not shown that Darwinism must be formulated in teleological terms, nor does this argument rule out my modified (E) view.
3. Now this is where an insuperable problem for materialism comes in. If you take View E, then you have to say that teleology, purpose, “directedness” or “pointing toward” of any kind is an illusion. But illusions are themselves instances of “directedness” or “pointing toward.” In particular they are instances of intentionality, where intentionality is what the “directedness” or “pointing toward” that is definitive of teleology in general looks like in the case of mental states (thoughts, perceptions, volitions, and the like) in particular. This is why the intentionality of the mental has notoriously been difficult for the materialist to account for. For materialism maintains that there is no irreducible “directedness” in the world, yet intentionality just is a kind of “directedness.” A thought or perception is about or directed at a state of affairs (whether real or illusory), a volition is about or directed at a certain outcome (whether actually realizable or not), and so forth.Ed now assimilates intentionality to purpose, via what amounts to a pun on 'directedness'. The sense of directedness in intentionality is not the sense of entailment that I claim for purposiveness. The directedness of intentional states is a quasi-relation between thoughts and objects. The directedness of purposiveness, or so I claim, is the entailment relation between thoughts. So a denial of purposiveness in the material realm need not rule out the intentionality of the mental realm, even if the former provides the material substrate of the latter. The difficulty for materialism of accounting for intentionality is not due to the lack of purposiveness in the material realm.
4. As materialists like Alex Rosenberg and Paul Churchland see, this is why a consistent materialist really has to be an eliminativist and deny the reality of intentionality altogether. The problem is that this simply cannot coherently be done. To be sure, the eliminativist can avoid saying blatantly self-contradictory things like “I believe there are no beliefs,” but that doesn’t solve the basic problem. For he will inevitably have to make use of a notion like “illusion,” “error,” “falsehood,” or the like even just to express what it is he is denying the existence of, and these notions are thoroughly intentional (in the sense of being instances of intentionality). For one to be in thrall to an “illusion” or an “error” just is to be in a state with meaning, with directedness on to a certain content, and so forth. In short, to dismiss the “directedness” or “pointing toward” characteristic of teleology and intentionality as an illusion is incoherent, since illusions are themselves instances of the very phenomenon whose existence is being denied. We saw in a recent series of posts how Rosenberg tries to solve this incoherence problem -- in an attempt that is, to his credit, more serious than that of other eliminativists -- but fails utterly.I wouldn't want to deny intentionality, though I don't think it's all it's cracked up to be. It's not at all clear to me that intentionality is captured through this notion of 'directedness'. It's only through his conflation of the apparent directedness of intentionality with the hypothetical directedness of teleology that Ed thinks that the denier of teleology must deny intentionality. And that's down to a rather bad pun.
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