Monday, February 7, 2011

Putnam on causation, intentionality, and Aristotle

For the last three centuries a certain metaphysical picture suggested by Newtonian or Galilean physics has been repeatedly confused with physics itself.  (More recently, metaphysical pictures suggested by biology and by computer science have been confused with those subjects themselves, in much the same way.)  Philosophers who love that picture do not have very much incentive to point out the confusion – if a philosophical picture is taken to be the picture endorsed by science, then attacks on the picture will seem to be attacks on science, and few philosophers will wish to be seen as enemies of science.

Hilary Putnam, Renewing Philosophy (p. 19)

I recall that, while in grad school, a fellow student and I once lamented that Hilary Putnam – who by the 1980s had abandoned the scientism and naturalistic reductionism that had characterized his early work – had gone soft philosophically.  I think this was a common attitude in those days.  What idiots we were.  In fact Putnam had become an even more serious, nuanced – and indeed rigorous – thinker than he already had been.  That is why he took the turn he did: He saw that the dogmas to which he had been committed (and to which so many contemporary academic philosophers still are committed) simply did not do justice to the facts, to the richness and complexity of the real world.

A central yet insufficiently appreciated element of Putnam’s critique of naturalism is his view that intentionality cannot be accounted for in causal terms, and that (the relevant notion of) causation itself cannot be accounted for in physicalistic terms.  (This is related to, but distinct from, his well-known “model-theoretic argument” against certain versions of realism.)  This is a theme that crops up over and over again in Putnam’s later work.  It is most fully developed in his 1992 book Renewing Philosophy – a volume filled with interesting things, and which anyone who wants to understand contemporary analytic philosophy should read.  Important relevant material is also to be found in his paper “Is the Causal Structure of the Physical Itself Something Physical?” (available in his collection Realism with a Human Face), his book The Many Faces of Realism, and his paper “Aristotle after Wittgenstein” (in his collection Words and Life). 

Causal theories of intentionality try to show that a neural state or process B will represent or stand for some object, event, or process A if B is caused by A in the right sort of way.  If a certain neural structure bears the right sort of causal relation to cats, for example, then it will represent cats.  The trick is to spell out what the “right” sort of causal relation involves, in a way that avoids certain well-known counterexamples.  (We looked at how Fred Dretske tries to accomplish this in an earlier post.)  Biological or “biosemantic” theories of intentionality are essentially a Darwinian riff on the causal approach, tracing the causal chains claimed to underlie intentionality beyond our immediate environment and back to the environment in which the brains of our ancestors were shaped by natural selection.

Putnam does not think either sort of theory can work.  Take the latter first.  Biosemantic theories claim that a neural state or process B will represent some object, event, or process A if B was selected for because of some advantage it provided vis-à-vis A.  So, consider the suggestion that a certain neural “data structure” evolved in dogs to facilitate their getting meat, and that this justifies us in attributing to them a concept or “proto-concept” of meat (Renewing Philosophy, pp. 27-33).  As Putnam points out, a dog will be satisfied and nourished whether it is given fresh meat, canned meat, or some textured vegetable protein that looks, smells, and tastes exactly like meat.  For that reason, there is no fact of the matter about whether its putative “proto-concept” represents any one of these in particular, and thus no sense to be made of the question of whether the dog has a true belief about what it is eating when it eats the vegetable protein rather than meat.  “Evolution didn’t ‘design’ dogs’ ideas to be true or false, it designed them to be successful or unsuccessful” (Renewing Philosophy, p. 31). 

But in that case, Putnam says, the suggestion that the dog really has a “proto-concept” of meat in the first place is groundless:

[T]he whole idea that a unique correspondence between the data structure and meat is involved in this bit of natural selection is an illusion, an artifact of the way we described the situation.  We could just as well have said that the data structure was selected for because its action normally signals the presence of something which has a certain smell and taste and appearance and is edible.  (Renewing Philosophy, p. 31)

In short, there is nothing in the situation described that entails that anything in the dog’s brain corresponds to meat specifically, and thus there is nothing in the situation that entails that the dog has a concept (or “proto-concept”) of meat.  The point is completely general, applying to any concept.  Natural selection favors survival value, not truth or falsity.  Hence you are not going to get truth or falsity from natural selection, and neither will you get from it the concepts that thoughts and statements – the sorts of things that are susceptible of being either true or false – presuppose.

Indeed, the very idea that the evolutionary processes under discussion have anything to do with explaining the origin of intentionality in the first place is an illusion.  After all, gazelles’ legs were favored by natural selection because they allowed gazelles to run fast and thereby to escape predators.  But no one suggests that this shows that a gazelle’s leg has the concept of running fast, or the thought that now would be a good time to run.  As Putnam writes:

Isn’t it with dogs as with gazelles?  Dogs which tended to eat meat rather than vegetables when both were available produced more offspring (gazelles which ran faster than lions escaped the lions and were thus able to produce more offspring).  Just as we aren’t tempted to say that gazelles have a proto-concept of running fast, so dogs don’t have a proto-concept of meat…  The “reference” we get out of this bit of hypothetical natural selection will be just the reference we put in our choice of a description.  Evolution won’t give you more intentionality than you pack into it.  (Renewing Philosophy, pp. 32-22)

In other words, in order to make the evolution of certain neural structures relevant to the explanation of intentionality, a “biosemantics” theorist has to presuppose that such neural structures “represent” the external world in a way that the gazelle’s leg structure (say) does not; he is reading intentionality into the biological facts, not deriving it from them.

Causal theories also subtly presuppose what they are purporting to explain.  Criticizing Jerry Fodor’s version of the causal theory, Putnam notes that in everyday claims about causation, we typically distinguish between “contributory causes” or “background conditions,” on the one hand, and “the cause” of an event on the other.  For example, if we say that a stuck valve caused a certain pressure cooker to explode, we are treating the stuck valve differently than the way we treat (say) the lack of holes in the vessel of the pressure cooker, even though the latter also played a role in the explosion.  The lack of holes we treat as a contributory cause or background condition; the stuck valve we treat as “the cause,” as being of special significance.  Putnam observes:

Yet, in the physics of the explosion, the role played by the stuck valve is exactly the same as the role of [the lack of holes]: the absence of either would have permitted the steam to escape, bringing down the pressure and averting the explosion. (The Many Faces of Realism, pp. 37-38)

For in fundamental physics, at least, one usually ignores the distinction between contributory causes and “the cause”, and tries to provide a formalism which shows how all of the factors interact to produce the final result.  (Renewing Philosophy, p. 50)

Though it has no unique significance to the physics of the situation, we treat the stuck valve as special, Putnam says, because of our interests.  We take it that

the valve ‘should have’ let the steam escape – that is its ‘function’, what it was designed to do.  On the other hand, the surface element [present where a hole might otherwise have been] was not doing anything ‘wrong’ in preventing the steam from escaping; containing the steam is the ‘function’ of the surface of which [this element] is a part.  So when we ask ‘Why did the explosion take place?’, knowing what we know and having the interests we do have, our ‘explanation space’ consists of the alternatives:

(1) Explosion taking place

(2) Everything functioning as it should

What we want to know, in other words, is why 1 is what happened as opposed to 2.  We are simply not interested in why 1 is what happened as opposed to such alternatives as:

(3) The surface element … is missing, and no explosion takes place. (The Many Faces of Realism, p. 38)

Now, insofar as the distinction between “the cause” and contributing or background conditions is in this way “interest-relative” and “context-sensitive,” it presupposes the existence of our powers of representation or intentionality, for

being interested in something involves, albeit in a slightly hidden way, the notion of “aboutness”, that is, the central intentional notion.  To be interested in something, in this sense, you have to be able to think about it – you have to be able to refer to it, in thought or in language.  (Renewing Philosophy, p. 50)

The reason this is significant is that the aim of a causal theory is to explain intentionality or representation in purely physical terms – terms that make no reference to concepts other than those recognized by physical science.  Yet given their actual examples, causal theorists in fact help themselves to a “notion of things ‘causing’ other things [which] is not a notion… simply handed to us by physics” (Renewing Philosophy, p. 50) – namely, the everyday notion that presupposes the interest-relative distinction between “the cause” and contributing or background conditions.  That is to say, they make reference to ordinary objects – cats, the valves on pressure cookers, and the like – in a way that gives them a causal significance they do not have in the sorts of explanations physics offers.  Nor is it easy to see how these theorists can avoid doing this, given that their aim is precisely to explain how we can represent such everyday objects in thought and language.  But in doing it they are subtly presupposing the existence of intentionality – the very phenomenon they are supposed to be explaining.

The bottom line, as Putnam puts it in “Is the Causal Structure of the Physical Itself Something Physical?”, is that “Nature, or ’physical reality’ in the post-Newtonian understanding of the physical, has no semantic preferences” (p. 83, emphasis mine).  There is nothing in the physical facts so conceived that can determine why any particular causal chain “can be singled out as ‘the’ relation between signs and their referents” (p. 89).  On the Aristotelian conception of nature championed by the medieval Scholastics, material substances and processes were inherently “directed towards” certain ends or “final causes” beyond themselves, given their “essences” or “substantial forms.”  A kind of meaning was built into the material world from top to bottom.  But the early modern philosophers and scientists defined themselves against this essentialist and teleological view of nature, embracing a “mechanistic” picture of the world as devoid of any inherent formal or final causes – a picture contemporary naturalists take for granted.

Yet, as Putnam argues, causal theorists of intentionality, though officially committed to the anti-Scholastic, anti-Aristotelian revolution of the early moderns, are also implicitly beholden to “a notion according to which what is normal, what is an explanation, what is a bringer-about, is all in the essence of things in themselves”; and they are thereby beholden, in effect, to “a medieval notion of causation” (p. 88, emphasis added).  For the idea that there is an “intrinsic distinction” between the cause of an event and mere background conditions “has much more to do with medieval (and Aristotelian) notions of ‘efficient causation’ than with post-Newtonian ones” (The Many Faces of Realism, p. 26).  It presupposes an “Aristotelian conception of form” – of “self-identifying structures” which objectively demarcate the ordinary objects of our experience from each other in a way they are not demarcated by modern physics (“Aristotle after Wittgenstein,” pp. 68-69).  And if we implicitly affirm such notions in the course of giving a causal account of intentionality, “then we abandon materialism without admitting that we are abandoning it” for in that case we “project into physical systems properties… that cannot be properties of matter ‘in itself,’” at least not given the post-Newtonian conception of matter to which materialists are committed (“Causal Structure,” p. 90).

Here, and in the quote with which I began this post, Putnam might sound a bit like the author of The Last Superstition (minus the polemics and right-wing politics, anyway).  Indeed, Putnam allows that the considerations he raises are “grist for the mill of a possible latter-day Aristotelian metaphysics,” and that an Aristotelian might naturally respond “I told you so.  You cannot do without the notion of form” (“Aristotle after Wittgenstein,” p. 69).  As I have noted many times (e.g. here), materialists constantly help themselves to concepts to which they are not entitled given their basic assumptions about the nature of matter, but which make perfect sense on a broadly Aristotelian or Scholastic set of assumptions.  They don’t see this because most of them know, if anything, only caricatures of Aristotelianism and Scholasticism.  Nor, given the ideological interests noted by Putnam, do they have much incentive to try to see beyond the caricatures.

Putnam, a better informed and non-ideological philosopher, does see what is going on.  But he does not himself go in a neo-Aristotelian direction, opting for pragmatism instead.  I’ll address his reasons in a future post.  (Meanwhile, our pal Bill Vallicella has recently posted on Putnam’s argument himself.  Take a look.)


  1. So a thorough-going naturalist would be forced to describe the world wholly in these terms: "and then this molecule moved closer to those ones over there, and entered into a chemical bond, and then the bond was broken when struck by an ion..." There would never, never be a reason for looking at the macro level of say the cell, much less a full organism, because there is nothing that distinguishes any clumps of molecules from non-clumps other than mere location, and location has no meaning. To call an animal a "thing" is to designate meaning to its skin that separates "it" from the stuff on the other side of the skin, and this presumes intentionality for the skin. To call a tree a tree means to recognize an organic unit, which implies intentionality that cannot be found in merely stating the arrangements of the molecules in a temporary spatial clumping, it presumes there is meaning to the clumps of leaves that makes them different from the clump of molecules of caterpillar on the leaves. You would have no basis to note the clumps as distinct unless there was something intentional about them.

  2. Exactly.

    And he still miles to go before escaping his original mistakes.

    "In fact Putnam had become an even more serious, nuanced – and indeed rigorous – thinker than he already had been."

  3. Thanks for the excellent post, Ed.

    What introductory Putnam would you recommend an undergrad with a so-so familiarity with contemporary analytic philosophy? Thanks.

  4. Maybe I'm a bit OT here, but I'd really like to hear/read your conversion story someday.

    If I am not wrong you used to be an atheist (or at least a non-Christian), and the study of philosophy brought you to the faith. (if I am wrong I apologize)

    I think that would be a very interesting tale!

  5. Anon,

    I think Renewing Philosophy is definitely the one to start with.


    I'll think about it.

  6. I started with Philosophy of Logic. Short but good. Putnam is a giant.

    Ed -- what are your thoughts on Kripke's argument against materialism, as presented in Identity and Necessity?

    Cheers, -- D.

  7. Just a quibble that bolsters Putnam:
    Common sense says that the fire beneath the boiler, or rather the heat it has been putting in recently, was the Cause of the explosion,
    but the stuck valve was Responsible.

    In fact the most immediate cause of the explosion is the sudden pressure release allowing the water's internal energy to cause the phase change. If the boiling is fast enough, the consequent high vapor pressure leads to a shock wave, which properly constitutes the explosion.

    Causality is thought to be direct, immediate, and discernible, while Responsibility can be more indirect, since it also includes the actions and results of everybody who designed and built the boiler, all the way back to the iron mines and gas wells. Responsibility would also have to include all the design properties of the boiler and its constituent materials, including how it would behave in an infinity of possible situations. Causality's penumbra spreads far.

    A hole is only one of a multitude of defects that could prevent an explosion, such as lack of insulation or a burner that can't stay on long enough. You can imagine an infinite number of lacks that allowed the explosion, but we know the stuck valve is different. It has a non-infinitesimal probability of being stuck closed. As a strategic single-point failure this particular lack turns out to be the most frequent 'cause' of every boiler explosion that ever happened, even though all were actually caused by their fires. We call a bad valve the 'cause' because when you fix it the fire won't be able to cause another explosion. A bullet puncturing the tank badly enough for it to suddenly rupture would be a different direct cause than from the fire, one requiring Kevlar rather than a relief valve.

    This exercise of our common-sense concept of causality shows that engineering concepts are an intrinsic part of it. Engineering is of course 100% intentionality, so trying to derive intentionality from causality is definitely cart-before-the-horse folly.

  8. Dr Feser,

    What would you reccomend to someone (me) interested in learning how a neo-thomist theory of science would work?

    I have read your books Philosophy of Mind and Aquinas. I'm currently doing a PhD in Science so of course know very little about the philosophy of science! (other than that picked up by general interest in theology and philosophy).

    I plan to read TLS soon, but is there anyone else you recommend?

  9. Chariots,

    You might want to take a look at "The Modeling of Nature" by William A. Wallace which provides a nice synthesis of Aritotelian Philosophy of Nature with the modern emperiometric scientific approach.


  10. I have not yet read this post, so I am just making a general that just truck me, since this post seems apt enough.

    I'm listening to Doc Feser's interview with Turek and I realized I sometimes feel bad for Ed.

    I mean, I don't know how many times I've seen it happen on this blog alone (not to mention my own blog and various ther venues I occasionally visit): the mechanist (post-/anti-Aristotelian) comes in swinging saying form and finality adds nothing to science, our knowledge of the world, etc. Then, after a series of patient and enlightened responses and repartees, the critic concedes, "Well, if THAT'S what you mean by finality and formality, well, yeah, of course I accept that. That's how science works. But that doesn't mean Thomistotelian metaphysics is right." Cue, as they say, a facepalm.

    The Chinese have a saying (which is almost a tautology, I know): "見山不是山而見山又是山 (Seeing the mountain is not the mountain, yet the mountain seen is the mountain)。" That's the melancholy I feel at this moment: critics concede that the mountain of formal-finality is evident yet deny that's not "really" what Aristhomism is getting at. It's just GOT to be more arcane and 'medieval'.

    Anybody feel me?

  11. Codgitator: absolutely! I'd classify this sort of response into three main types: the misosophists refuse to acknowledge that the concepts are valid at all. You can point out that at best they're saying something similar in different words, but they still insist that the philosophy is simply useless and/or wrong. They are in one way the most frustrating since anyone who hates philosophy is, almost by definition, a lost cause. On the other hand, they are also the most easily seen through by anyone who does not hate philosophy.

    Then there are those who are willing to concede that, all right, once you get past all the obsolete terminology that philosophers persist in employing (because they don't know enough science, you see), then yes, there are some relevant ideas in there (already covered by science, of course), but you can't expect anyone to take the whole thing seriously nowadays with all that superstitious metaphysical baggage along for the ride.

    And finally there are those who are actually willing to learn and will accept that the ancients and mediaevals were actually onto something. Then they will promptly suggest that philosophers adopt a more modern approach, since it comes down to the same thing really, and any specific devotion to the thought and language of Aristotle/Aquinas/etc. is just being a reactionary stick-in-the-mud. (The worst part being that this group includes a lot of professional philosophers, alas!)

  12. Putnam in the 60s & 70s was a Maoist -- and yes that is sickening.

    Putnam never made the flip from Frege & Carnap to Wittgenstein & Kuhn, so ultimately his work still sucks, though it is technically admirable and it moves from far worse to far better -- and helps some understand just a bit why the far worse is problemtic.

  13. Would Putnam's criticism apply to someone who was a conceptual role theorist? I would have thought that such a person could accept that content is context-relative, but would regard each person's holistic conceptual network as determining the meaning for that person. Doesn't this not make content context-relative to that person’s conceptual network, yet nevertheless naturalized? Am I missing something?