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Thứ Sáu, 29 tháng 6, 2012

As I noted in a recent post, the Spring 2012 issue of Theoretical and Applied Ethics contains a symposium on Ethics, Atheism, and Religion, with a lead essay by atheist philosopher Colin McGinn.  I wrote one of the responses to McGinn’s piece, and one of the other contributors, Steve Fuller, wrote an essay with the title “Defending Theism as if Science Mattered: Against Both McGinn and Feser.”  What follows is a reply to Fuller.  (Readers who have not already done so are advised to read McGinn's essay, mine, and Fuller’s before proceeding.  They're all fairly brief.)

Fuller contra McGinn

My piece was very critical of McGinn, and as the title of his contribution indicates, Fuller is critical of McGinn as well.  But our criticisms are significantly different, and in fact I would take issue with some of what Fuller has to say against McGinn.  In particular, Fuller seems to think that McGinn’s “belief… in the ultimate efficacy and significance of scientific inquiry” is one that “presuppose[s] the existence of God, specifically, the monotheistic deity of the Abrahamic tradition,” whether McGinn realizes this or not.  Fuller also indicates that he thinks that “from a strictly Darwinian standpoint” the value we place in science “is very puzzling.”  In the absence of “a belief… that we are created ‘in the image and likeness of God,” Fuller says, “it is not at all clear why we should continue to hold science in such high esteem.”

He is not much more explicit than that and I would not want to put words in his mouth, but it would seem that what Fuller is claiming is that a high degree of confidence in science is justifiable only if we suppose that both the order of the universe and the reliability of our cognitive faculties are guaranteed by a divine intelligent designer.  (I interpret him as taking this position both on the basis of what he says in this essay and because Fuller has been associated with the “Intelligent Design” movement.)

If this is Fuller’s argument, then in my view it is much too quick.  I agree that neither the order of the universe nor the reliability of our cognitive faculties are intelligible given the conception of the material world associated with naturalism.  But from the falsity of this conception, the truth of theism does not automatically follow.  For suppose that (as I have argued in several places) the Aristotelian teleological and essentialist conception of the material world is correct.  Then the immediateexplanation both of the order that exists in the natural world and of the reliability of our cognitive processes is to be found in the natures of material substances themselves -- in particular, in their substantial forms and in the teleology or directedness toward an end that is immanent to them given their substantial forms.  

Does this inherently teleological and essentialist natural order itself require an explanation in terms of a divine cause?  I certainly think so (and have argued for that conclusion too in several places).  But that claim requires further argumentation.  For the Aristotelian-Thomistic (A-T) tradition -- in contrast to the “design argument” associated with Paley -- we cannot go directly from the existence of order in the world to a divine intelligence; an intermediate step is required.  And the reason is that A-T is opposed to the whole picture of the universe as a kind of artifact and God as a cosmic artificer, at least insofar as this picture implies that there are no inherent essences or teleology in nature.  The time-telling function of a watch is not in any way inherent to the parts of a watch but derives entirely from its maker; hence if you know that something is a watch, it follows directly that there must be some intelligence that put that function into it.  But the teleological features of natural substances are inherent to them; that’s what makes them natural (in the A-T sense of the “natural”).  Hence it makes no sense to treat them as comparable to “watches” in need of a “watchmaker.”  That’s just the wrong way to proceed in arguing from the world to God.  (See my many posts on the dispute between A-T and ID theory for more on this subject.  And see The Last Superstition, Aquinas, and my American Catholic Philosophical Quarterly article “Existential Inertia and the Five Ways” for defense of the main A-T arguments for the existence of God.  You can read the latter online by Googling the article’s title, going to about the third search result, and clicking on “Quick View” just below the link.)

Indeed, it is only on the A-T sort of view, rather than the Paley sort of view, that science is intelligible.  For even though God is the ultimate cause of the world and its intelligibility, we do not need directly to appeal to Him or His intentions in order to understand the specific ways in which natural substances and processes work.  For example, even though God is the ultimate source of all causal power, you can know that sulfuric acid will corrode metal without having to make reference to Him, because that is the sort of effect sulfuric acid will have given its nature.  And you can know that roots are for taking in water and nutrients and that eyes are for seeing just by studying roots and eyes themselves, without reference to the intentions of a designer, because that is what they are for given theirnatures.  Science is possible precisely because natural substances have essences, teleology, and causal power immanent to them, and thus knowable apart from the intentions of their Creator -- precisely because it is really they who act, and not God who does everything, as in the occasionalistpicture of divine causality.  The immanent or “built in” character of the essences and teleology of natural substances goes hand in hand with the A-T view (which occasionalism denies) that natural substances are true secondary causes.  And to deny that they are true secondary causes is implicitly to deny that there is a natural order for science to uncover.  (Indeed, as I have argued elsewhere, part of the problem with the view of nature implicit in arguments like Paley’s is that it tends -- even if Paley and his defenders do not intend this -- to collapse into either occasionalism or deism.)

There is a parallel here to the A-T conception of natural law.  Human beings, like every other natural substance, have for A-T a nature or substantial form, and what is good for them is determined by the ends or final causes that follow upon having that sort of nature or substantial form.  But just as we can normally determine the efficient causes of things without making reference to God, so too can we normally determine the final causes of things without making reference to God.  And thus, just as we can do physics, chemistry, and the like without making reference to God, so too can we do ethics without making reference to God, at least to a large extent.  For we can know what is good for a thing if we can know its nature, and we can know its nature by empirical investigation guided by sound (A-T) metaphysics.  At least to a large extent, then, we can know what the natural law says just from the study of human nature and apart from any sort of divine revelation.  That’s why it’s the natural law.  (And just as the conception of nature associated with Paley threatens to collapse into occasionalism -- on which it is only ever God who does anything, with nature contributing nothing -- so too does the view that ethics depends directly on God threaten to collapse into a view of morality as a set of arbitrary divine commands, with human nature contributing nothing.  I have addressed these issues in an earlier post.)

In my view, then, religious apologists make a serious mistake when they try to go directly from the reliability of science or the reality of objective morality to the existence of God.  One reason this is a mistake is that such arguments are unsound.  To show that the conception of nature associated with naturalism is false is, for the reasons I’ve indicated, not by itself to show that theism is true.  Another reason is that this sort of approach tends, in the ways I have also indicated, to lead to a seriously inadequate conception of God’s relationship to the world.  The right approach to natural theology (as I have argued in a recent post and also in the YouTube lecture linked to above) is to begin with premises drawn, not from natural science, but from the philosophy of nature and/or metaphysics.

Fuller contra Feser

If Fuller’s response to McGinn is inadequate, his criticisms of me are, not to put too fine a point on it, bizarre.  His remarks are equal parts hostile, unfounded, and inaccurate right out of the gate, as he begins his attack on my views by writing:

I do not buy into Feser’s self-serving, question-begging construct, “classical theism,” or his corresponding charge that McGinn is “pre-theistic.”  My guess is that in keeping with a certain strand of Catholic sophistry, Feser wants to banish the very idea of atheism as conceptually incoherent, and [sic] that self-avowed “atheists" are simply people who have yet to master the classical theist’s way of making sense of God…. [Feser] want[s] to ring-fence God from serious epistemic contestation…

Where exactly I have “begged the question” Fuller never tells us.  As to the accusations that I resist “serious epistemic contestation,” charge atheism with being conceptually incoherent, and claim that no one who understands classical theism could fail to believe it, what I actually wrote in my reply to McGinn was precisely the opposite.  I said:

A reasonable person might reject such alleged proofs [of classical theism], but to characterize the debate the way McGinn implicitly does is to make a basic category mistake…

and

Now, a critic might intelligibly question whether the arguments for such a divine Cause succeed… But to suggest that belief in the God of classical theism is relevantly comparable to believing in Zeus, werewolves, ghosts, or Santa Claus is to miss the whole point.

and

The point has nothing to do with whether or not classical theism is true, or with whether the arguments for it are ultimately any good.  Even if the atheist were correct, that would not be because it turned out that the God of classical theism really was the sort of thing that could intelligibly be said to require a cause of his own, or was composed of parts, or was merely one instance of a kind among others.

But it seems that Fuller’s animus is actually inspired, not by any purported unfairness on my part toward atheists, but rather by my objections to his own preferred conception of God.  He writes:

[Feser] basically wants to rule out of the discussion those who would argue that divine qualities differ from human ones only by degree and not kind.  Such a person, I include myself, holds that God is an infinite being, but the dimensions along which God is infinite are the same ones in virtue of which humans prove finite.  In that respect, if you scale up all of our virtues indefinitely and imagine them contained within one being, then you have God…

[T]his would not be Plato’s or Aristotle’s way of seeing things… but it would be familiar from defenders of a nominalist approach to universals and an univocal approach to predication, starting with the high mediaevals Duns Scotus and Ockham and leading to Hobbes and Mill in the modern period.  Indeed, it is the theological tradition whose bloody-minded literalness in envisaging God as the cleverest mechanic working with the most tools in the largest possible shop that [sic] animated the imaginations behind the 17th century Scientific Revolution.

Feser demonizes the nominalist tradition as "anthropomorphic" and "personalist" in its conception of God, as if that were a kind of intellectual corruption, if not blasphemy, or [sic] some otherwise settled sacred truth.

End quote.  Now, if Fuller wants to defend theistic personalism, univocal predication, nominalism, etc. he’s welcome to go for it.  I never “ruled out of the discussion” those who would defend such views; I simply disagree with them and have presented arguments against them.  That’s discussion, not a refusal to discuss.  (I address the dispute between classical theism and theistic personalism here, here, here, here, here, and here, and in some of the posts on the dispute between A-T and ID linked to above.  I have discussed the baneful theological and philosophical consequences of nominalism here and here.  These themes are also dealt with in The Last Superstition and Aquinas.)

Does Fuller have anything to offer other than pique?  Not much.  It is evident that one thing he likes about the doctrines in question is that they were, as a matter of historical fact, embraced by the fathers of the scientific revolution.  Is Fuller therefore claiming that they are logicallylinked to science, so that to accept science one has to embrace theistic personalism, univocal predication, and nominalsm?  Evidently not, for he allows that “Feser, in good Thomist fashion, can logically accommodate a version of scientific inquiry within what he calls ‘classical theism.’”  

So what’s the problem?  Fuller’s answer is as follows:

[O]n Feser’s view, science appears doomed to dwell in a shadow universe vis-à-vis the protected ontological zone reserved for theology.  While this neatly tracks the modern political separation of state and church, it undermines any strong reading of the New Testament doctrine of logos, whereby through language humans partake of the deity’s creative potential.  Without such an interpretation, which is arguably more concerned with the Bible’s literalness than its truth, Christians would not have been emboldened to make the great leap into the modern scientific world-view.

I must confess that I’m not sure what all of this means; or at least, I cannot find within it anything that is both (a) an argument and (b) remotely plausible.  Take the claim that on my view “science appears doomed to dwell in a shadow universe vis-à-vis the protected ontological zone reserved for theology.”  Is Fuller complaining that I think science can be conducted without reference to theology?  If so, then as I indicated above, I think that is indeed essentially the case.  But it obviously is the case, since scientists do it all the time.  They can determine the structure, function, causal powers etc. of tree roots, eyes, sulfuric acid and the like without asking themselves “Hmm, now what exactly did God have in mind when He made a world with roots, eyeballs, sulfuric acid, etc.?”  Empirical science is the study of the natures of material things; it isn’t a kind of roundabout divine psychology, an indirect way of reading God’s mind.  When the biologist discovers something about the structure of tree roots, it really is tree roots that he knows about, and when the chemist discovers something about the structure of sulfuric acid, it is really sulfuric acid that he knows about.  That is why a scientist can find these things out even if he is an atheist.  (Does Fuller deny this?  Presumably not.)

But doesn’t this entail that the world that science reveals to us could exist without God?  Not for a moment.  Determining that sulfuric acid has specifically this kind of effect rather than that requires no reference to God; but that sulfuric acid and anything else have any causal power at all in the first place, even for an instant, is unintelligible without God as Uncaused Cause.  That roots develop in this specific way rather than that can be known without reference to God; but that any change occurs in the world at all is unintelligible without God as Unmoved Mover.  It requires no theological knowledge at all to realize that eyes are “directed at” seeing, specifically, as their natural end; but that anything is directed to any natural end at all, even for an instant, is unintelligible without God as Supreme Intelligence.  

Arguments like the Five Ways establish these conclusions.  But they are not scientificarguments -- not because they are lesssecure than science but because they are moresecure, because they start, not with premises about this or that particular aspect of the natural world (which is what science is concerned with), but rather with premises concerning the very possibility of there being any empirical world at all for science to study in the first place.  That is to say, their premises are drawn from the philosophy of nature and/or metaphysics rather than from natural science (as, again, I explained in a recent post).

What about Fuller’s claim that this “undermines any strong reading of the New Testament doctrine of logos, whereby through language humans partake of the deity’s creative potential”?  Once again I’m not even sure what Fuller means.  Is he claiming that classical theism and/or the A-T view of the relationship between theology and science is incompatible with the Christian doctrine that human beings are made in the image of God?  How, exactly?  After all, the A-T view of human nature, which I endorse, is that our distinctively intellectual powers -- on which language rests -- cannot in principle be given a materialistic explanation, and that it is precisely these immaterial intellectual powers that make it true that we are made in God’s image in a way nothing in the rest of the material world could be.  How exactly is this undermined by the A-T view of science?

The only other thing Fuller has to offer in the way of something like an argument against me is the following defense of nominalism:

While Feser is undoubtedly correct that an idealized triangle differs significantly from actual ones, including those drawn to represent the ideal, the key point is not the difference but the similarity. In effect, the ideal triangle serves as a goal or standard, against which actual triangles may be judged, so as to result in measures of distance and, by implication, progress towards realizing the ideal.  It follows that actual triangles are not imperfect versions of some pre-existent ideal but works in progress towards reaching a vividly imagined ideal. The ideal triangle exists for us more as a hypothesis than an indubitable a priori concept, let alone a metaphysical foundation.

Once again it takes a little effort to discern the argument within the murk, but it seems to be this:

1. The ideal triangle serves as a goal or standard, against which actual triangles may be judged, so as to result in measures of distance and, by implication, progress towards realizing the ideal. 

It follows that

2. Actual triangles are not imperfect versions of some pre-existent ideal but works in progress towards reaching a vividly imagined ideal.

But the argument is no good.  Fuller’s claim, as far as I can make out, is that the idealized triangle by reference to which we judge material triangles to be imperfect exists only in the mind, and not in any mind-independent reality.  But while this might conflict with Platonic realism, it is exactly what is affirmed by Aristotelian realists, who take universals to exist only in either the things that instantiate them or in minds which grasp them, rather than in a Platonic third realm.  Hence Fuller’s argument hardly establishes nominalism; at most it would be incompatible with some version of realism, not all of them.

To be sure, Fuller speaks of “imagining” the ideal rather than (as realists would) of “conceiving” it.  Here I assume he is either being sloppy or doesn’t realize that there is a difference between forming a mental image of something and grasping it with one’s intellect.  On the other hand, perhaps Fuller knows exactly what he is saying and means to deny the distinction realists would draw between imagination and intellect.  But in that case his argument is just a blatant non sequitur, for from the premise that an idealized triangle exists only in the mind it doesn’t follow that the wayin which it exists in the mind is as a mental image rather than as an abstract concept.  (I’ve discussed the difference between images and concepts in several places, such as here.  As you’ll also see from that post, if Fuller thinks Aristotelian realism claims that concepts are “a priori” he is sorely mistaken.)

It is also true that Fuller says that the idealized triangle is not “pre-existent,” and at least some Aristotelian realists -- for example, Scholastics like Aquinas -- would say that it pre-exists its instantiations in the world in the divine intellect (which is not the same as a Platonic third realm distinct from anyintellect).  But it is hard to see how Fuller could consistently deny this aspect of the Scholastic realist position.  For since Fuller is keen on the idea of God as a kind of Paleyan watchmaker, he would presumably want to say that the idealized forms of things pre-exist in this watchmaker’s mind, as the patterns in light of which he makes things.  

Group hug!

To conclude on a positive note, let me express some agreement with both Fuller and McGinn.  McGinn is perhaps the most prominent advocate of the “mysterian” view that there are certain philosophically problematic phenomena (such as consciousness) which, though they have perfectly natural causes, will probably never be explained scientifically given the limitations on our cognitive powers.  As I have said on other occasions, I think this is the most plausible way for a naturalist to deal with the difficulties facing his position -- and it is a principledway of doing so, given that the naturalist has independent, Darwinian grounds for holding that there are significant limits on our cognitive powers.  

This is one reason I have always found McGinn’s work very interesting (well, apart from what he has to say when he directly addresses religion, which is not very interesting or well-informed).  Fuller also has a kind word for McGinn’s mysterianism:

[T]o be fair to McGinn, he has form in refusing to defer to science as the final epistemic arbiter in matters of mind.  Indeed, he may be the most explicit of the "new mysterian" philosophers who deem consciousness, by virtue of its first-person character, to be beyond the reach of natural science.

So, some agreement between us all!

Except that mysterianism doesn’t work, at least not as a way to avoid theism, for reasons I have explained herewith some follow-up remarks here.  (See also my remarks on McGinn’s mysterian approach to consciousness in Philosophy of Mind.)

There, now I had to go and spoil all the ecumenical fun…

Thứ Hai, 25 tháng 6, 2012

Gene Callahan responds to my recent criticisms of his view that plants are sentient.  (Some plants or all?  Gene seems to think all of them are, though the evidence he appeals to would show at most only that some of them are.)  Recall that I had noted three reasons Aristotelians deny that any plants possess conscious awareness.  The first is that plants lack the specialized sense organs we find in animals.  The second is that plants lack the variability of response to stimuli that animals possess.  And the third is that sensation together with appetite and locomotion form a natural package of capacities, so that since plants lack locomotion they must lack sentience as well.

Gene focuses on the issue of locomotion, and claims that plants can indeed move in something like the way animals do.  In response to the example I gave of dry grass, which cannot move away from sources of heat or seek out water in the way animals can, Gene writes:

Plants can and do do things about circumstances like these.  For instance, the rhododendrons in my yard, in extreme heat, curl up their leaves, lessening water loss.  Plants that undergo periodic dry spells develop deeper root systems than those that do not.

and

[I]t is simply empirically false that plants do not move towards or away from aspects of their environments. They merely do so at a much slower rate than do animals, so it is not readily apparent that they are doing so.  But it has been found that plants "recognize" others of their own species, actively work to drive off plants of other species, and respond to insect attacks with counter-attacks of their own.

In a comment below my previous post, Gene adds:

"[F]linching" is about "moving away from bad conditions."  Plants do that.

The first thing to say in response to all of this is that to establish that something is capable of locomotion (which is what Aristotelians attribute to animals and deny to plants), it is not enough to show that there is some sense in which it “moves.”  Consider: A magnet will either push away from another magnet or draw toward it depending on which of the other magnet’s poles it is facing.  To take an example of “motion” in the broad Aristotelian sense of “change,” a pH test strip will change color when exposed to alkaline.  A wet kitchen sponge will return to its original size and shape after you squeeze it in your hand.  Or consider an instance cited by Bertrand Russell in his essay “Mind and Matter” of “the principle of the conditioned reflex, [which] though characteristic of what is living, finds some exemplification in other spheres.  For example: if you unroll a roll of paper, it will roll itself up again as soon as it can” (in Portraits from Memory and Other Essays, at p. 143).  And then there are examples of artifacts like smoke detectors and outdoor security lamps, which will activate in response to specific external stimuli.

Needless to say, none of these cases is plausibly regarded as involving sentience even though they all involve movement or change of some sort in response to the environment.  And this is so even though in some cases the response is vaguely analogous to the activity of living things -- specifically, to smelling or seeing (in the case of the smoke detector and security lamp), to self-preservation (in the case of the sponge), and to learned behavior (in the case of the rolled up paper).  So, to the extent that the plant movements cited by Gene are comparable to these, they cannot by themselves be indicative of sentience.

Of course, plants are, unlike these phenomena, alive.  And part of what it is, from an Aristotelian point of view, to be alive is to be the sort of thing that is the source of its own motions or changes.  (More precisely, it is to be the sort of thing that exhibits immanentas opposed to merely transeuntcausation.  I have discussed this distinction in some previous posts, such as this one and this one.)  But precisely for this reason, mere motion isn’t enough for the locomotion that the Aristotelian tradition regards as characteristic of animals and absent in plants.  As Aristotelian-Thomistic philosopher David Oderberg defines it in his book Real Essentialism, locomotion is “the capacity and tendency for self-movement from place to place in fulfillment of appetition” (p. 184, emphasis added) and it is, he argues “locomotion of the whole organism that gives evidence of sentience, not a mere reflex in one or other part of an organism that is otherwise rooted to the spot” (p. 188, emphasis added).  

Now one way to understand why sentience would be necessary to locomotion but not to other kinds of motion is as follows (where this is my way of stating things, not Oderberg’s, in case he would not want to commit himself to it!)  Because locomotion involves movement from one place to another, creatures capable of it need to be able to form inner representations of the objects and locations toward which they might move, representations that can guide that movement and that are variable enough to reflect alterations in the environment that arise as the creatures make their way from one place to another.  (For example, such representations need to be able to register the sudden appearance of a physical obstacle to further movement.)  Such creatures also need inner impulses that will cause them to initiate and sustain movement toward the objects of these representations, and those impulses also need to vary with alterations to the environment.  (For example, if a rival predator suddenly appears such a creature might have to shift from a desire to pursue a certain prey to a different impulse, either to fight or to flee.)  Now an animal’s ever-changing stream of conscious experiences performs exactly these functions; and that is, of course, precisely why animals have the complex nervous systems and sense organs they do.  Plants, by contrast, because they do not move from place to place, have no need of such inner representations and impulses and, unsurprisingly, lack anything like the neural and sensory structures that underlie such conscious awareness in animals.  Hence there is simply no reason to attribute sensation and appetite to them.

You might say that plants, unlike animals, need to be little more than stimulus-response mechanisms.  For that reason, behaviorism might be a good theory of plant psychology.  But of course, part of the point of behaviorism was that you don’t need to posit inner states in order to identify stimulus-response pairings -- which is why behaviorism is a lousy theory of animal and human psychology, i.e. the psychology of sentientcreatures.  

In another comment Gene replies to the point about the variability of response in sentient creatures, which is absent in plants.  In an exchange with Gene in the combox of my earlier post, reader Daniel Smith noted that “two identical plants would respond identically to the same stimulus.”  Gene responded

Daniel, there is no such thing as “two identical plants”… Go out and look at a bunch of maple trees one day, and try to discover two of them that are identical.

But here Gene commits a fallacy of equivocation.  His response assumes that his critic’s point is that two plants that are “identical” in the sense of being perfect twins, each indiscernible from the other, would react to stimuli in the same way.  And as he rightly points out, there aren’t many plants that are identical to each other in thatsense.  But that’s not the sense of “identical” in question here.  The point is rather that if you took two healthy plants of the same type and (say) two healthy dogs of the same type (whether you have “identical twins” in either case is irrelevant), you would never get out of the former the same variability of response to stimuli that you get out of the latter.  And this is evidence that you do not have in the former, as you do in the latter, inner sensory and appetitive states as intermediaries between the stimuli and the responses, the variability of which accounts for the variability of the responses.

Gene also comments:

And let's remember that fungii, which are vastly different to plants, living in an entirely different manner, do not even have a category in A-T [i.e. Aristotelian-Thomistic philosophy]!

(Gene had also made a big deal in his original post of the purportedly problematic status of mushrooms (!) in Aristotelian metaphysics.)

Now this is, of course, completely irrelevant to whether plants are sentient.  But it also reflects a misunderstanding of what Aristotelians mean by “vegetative” life.  Just as the use of “species” and “genus” in logic and metaphysics does not correspond exactly to the way those terms are used in biology, so too does “vegetative” in Aristotelian philosophy not track in a one-to-one way the use of terms like “plant” in biological science or in ordinary language.  It is used as a technical metaphysical term for those forms of life which, whatever their classification in contemporary biology, have capacities like nutrition, growth, and reproduction while lacking capacities like sensation, appetite, locomotion, rationality, or volition.  And in that technical, metaphysical sense both Fungi and Plantae count as “vegetative” even if they differ in various other ways.  (See Oderberg for discussion of this issue.)

Gene complains that:

In a seemingly common move by modern Aristotelians, [Ed] first plays the “but he doesn't really understand what we are saying” card.

Well, if the move is common, that is for good reason, as I have shown time and again (e.g. here, here, here, here, and here-- and the diligent reader with too much time on his hands can no doubt find many other examples in the blog archives -- not to mention hereand here).  And in his latest remarks Gene only provides a further instance of the phenomenon insofar as (with all due respect to Gene) his arguments rest on a misunderstanding of what Aristotelians mean by “vegetative” and “locomotion.”

Thứ Sáu, 22 tháng 6, 2012

Economist Gene Callahan (a friend of this blog) calls my attention to this article, which claims that plants are capable of “sensory” responses to their environments, and even that they “talk and listen to one another.”  Gene concludes that “contrary to Aristotle, plants are active and communicate to each other, with sounds among other methods” so that “neo-Aristotelians ought to drop the idea that plants lack sensations.”  And while Gene allows that “this certainly does not invalidate all of Aristotle's metaphysics,” it does in his view show that Aristotelians should be wary of once again “ma[king] the mistake of tying Aristotelian metaphysics to Aristotelian natural science.”

But (no disrespect to Gene intended) as usual with these breathless journalistic “Science has shown that…!” stories, the actual facts are far less exciting than the sensationalistic packaging would suggest.
  
What the article describes when it gets down to the details is the following:

Using powerful loudspeakers, researchers at The University of Western Australia were able to hear clicking sounds coming from the roots of corn saplings.

Researchers at Bristol University also found that when they suspended the young roots in water and played a continuous noise at 220Hz, a similar frequency to the plant clicks, they found that the plants grew towards the source of the sound…

[P]revious research from Exeter University found cabbage plants emitted methyl jasmonate gas when their surfaces are cut or pierced to warn its neighbors of danger such as caterpillars or garden shears.

Researchers from the earlier study also found that the when the volatile gas was emitted, the nearly cabbage plants appeared to receive the urgent message that [sic] and protected themselves by producing toxic chemicals on their leaves to fend off predators like caterpillars.

What has been shown, in other words -- if these claims are correct, anyway -- is that plants are sensitive to sounds (or at least to the vibrations associated with sounds) and to gases.  But so what?  Aristotelians, like everyone else, have long known that plants are in various ways sensitive to their environments -- that they will grow toward light, sink their roots in the direction of water, etc.  They have long known how a Venus fly trap will react to the presence of an insect and how the Mimosa pudica will respond to touch.  And they have long had a response to those who falsely suppose that these sorts of phenomena imply sentience.  Gene seems to think the article in question provides cutting-edge scientific evidence that “whether anything at all has a ‘vegetative soul’… it ain't plants.”  Yet the objection he raises is explicitly dealt with in books like George Klubertanz’s 1953 volume The Philosophy of Human Nature and Henry Koren’s An Introduction to the Philosophy of Animate Nature, published in 1955.  The subject is also treated at some length in David Oderberg’s recent Real Essentialism (at pp. 183-93).  What we have here, in the case of criticism of the Aristotelian conception of vegetative life (and with all due respect to Gene), is something often seen in criticism of Aristotelian ideas in natural theology, philosophy of mind, and ethics -- namely a failure to understand what Aristotelian writers actually mean by the technical terms they use, or to bother to read what they’ve written so as to find out what they mean.  

What Aristotelians do mean when they deny sentience to plants is not that plants are incapable of receiving information from their environments in ways that are in some respects analogous to sensation, but rather that in plants, unlike animals, there is no conscious awareness associated with the reception of this information.  In other words, what they mean is that there are nothing like qualia in plants, as there are in animals.  There’s something it’s like to be a bat, a dog, or a bird; but there’s nothing it’s like to be a tree, a blade of grass, or even a Venus fly trap.  That roots grow toward water doesn’t entail that plants feel thirst, and that plants grow toward light doesn’t entail that they feel heat or see the sunshine.  Similarly, if some plants are sensitive to vibrations and gases, it doesn’t follow that they hear or smell.

Nor is the reason Aristotelians would deny awareness to plants a matter of dogmatic a priori metaphysics (though metaphysical considerations have something to do with it).  As always when determining the natures of things, we must, for the Aristotelian, stick to the empirical evidence.  Koren writes:

It would be irrational to admit potencies implying awareness in plants if they do not show any signs of awareness, for one does not admit anything for which there is no evidence.  But in plants there are no signs of activity involving awareness.  Therefore, we cannot admit that plants have any potencies implying awareness, such as sensation and intellection.

The minor premise of this argument is attacked by opponents who point to so-called tropisms in plants, i.e. to the way they respond to physical stimuli… (p. 72)

Examples of the sort already mentioned follow, after which Koren says:

These facts would settle the argument in favor of sensation if they could be explained only as responses following upon the awareness of the physical stimulus by which they are provoked. But if these facts can be explained equally well without awareness, as purely physical and mechanical responses to physical stimuli, this explanation has to be preferred, because it would be unreasonable to assume the working of a higher cause for effects which can be explained equally well by a lower cause.  (Ibid.)

Yet there is simply nothing in the phenomena in question that requires attributing awareness to plants as opposed to mere unconscious sensitivity to certain specific environmental triggers (of the sort evident in, say, a smoke alarm or an outdoor security lamp).  Moreover, as Aristotelian writers emphasize, there are at least three key aspects of sensation in animals that are absent in the case of plants.  First of all, there are in animals specialized sense organs associated with their various forms of awareness -- eyes with visual awareness, ears with hearing, and so forth.  There is nothing like that in the case of plants.

Second, sensation in animals is associated with a variability of response that is not present in plants.  Unless it is in some way damaged, a plant will, say, simply grow toward the light or sink its roots downward in response to the relevant stimuli.  A properly functioning animal, by contrast, may respond in a number of different ways to stimuli presented to it.  For example, an animal might immediately leap toward the prey it sees, or sneak up toward it slowly, or refrain from acting at all if it sees another, stronger predator in the vicinity or some barrier it is afraid to cross.  A conscious perception functions as a kind of intermediarybetween external stimuli and different possible behavioral responses, an intermediary that makes this variability of response possible.  That plants lack such variability is thus a reason to think they lack anything like such intermediary, conscious states.

A third point -- one that combines specifically Aristotelian metaphysical considerations with empirical considerations -- is that for the Aristotelian, sensation naturally goes together with the other traditional characteristics of distinctively animal life, namely appetite and locomotion.  The three features are not, in the Aristotelian view, merely accidentally associated in animals, but form a kind of package.  An animal is aware of various aspects of its environment for the sake of the motions toward or away from those aspects that that awareness makes possible, and feels drawn toward or repelled by those aspects as a consequence.  Thus the absence of locomotive and appetitive powers in plants is evidence that awareness is absent as well, for awareness would be pointless in that case.  Indeed, it might even be harmful.  As Klubertanz writes:

For example, grass lacks the organic structure necessary for any form of sensation.  Moreover, it would be an evil for grass to have either sensation or appetite.  These activities would be useless, for grass has no power of external action which could be modified (controlled) by knowledge.  The activities would be directly an evil, for they would be a source of great suffering without any compensating advantage.  Nature is the source of operations for the good of the being; a nature which by supposition would be the source of operations for its own evil would be a contradiction.  (p. 58)

Hence, imagine that dry grass could feel the oppressive heat of the sun or experience thirst and the craving for water.  What would be the point?  It would not be able to do anything about its circumstances and would thus, unlike an animal, suffer without being able even in principleto remedy the circumstances leading to that suffering.   And this would violate the Aristotelian principle that nature does nothing in vain.  (But what about animals with disordered appetites or wounded or deformed organs?  Aren’t they counterexamples to the claim that nature does nothing in vain?  They are not, precisely because such animals are not in their natural state, precisely because they are in various ways deformed.)

Nor need one accept the general Aristotelian philosophy of nature to see the force of this consideration.  For how could conscious awareness evolve in a creature that was not capable of locomotion, given that the way such awareness typically manifests itself is via behavior and given that it is such behavior which would, presumably, be either adaptive or maladaptive?  Of course, the critic might respond that awareness might have developed as a “spandrel” in the Gould/Lewontin sense of being a non-adaptive byproduct of some other trait which was adaptive.  But there’s no point in suggesting that some trait is a spandrel until we know it exists, and whether awareness really exists in plants is precisely what is in question.  Furthermore, it is hard to see what mechanism there could be for awareness in plants even as a spandrel, given that they lack sense organs.  

(Note also that Michael Tye, arguing from a naturalistic rather than Aristotelian point of view, has given similar reasons for denying that plants have qualia.)

Those who claim that plants possess conscious awareness might at this point respond by saying that the notion of a “zombie” (in the philosophical sense) shows that conscious awareness has no adaptive value in any case, not just where plants are concerned but even where animals and human beings are concerned.  But there are two problems with such a response.  First, the Aristotelian will not agree that zombies really are metaphysically possible; as I have argued in several places (e.g. chapter 8 of Philosophy of Mind and chapter 4 of Aquinas), the notion of a zombie makes sense only against the background of a post-Cartesian, mechanistic conception of matter and not on an Aristotelian conception.  Hence to appeal to zombies would just be to beg the question against the Aristotelian.

Second, for the defender of plant sentience to appeal to zombies would only undermine his own case, for it would rob him even of the slender evidence on which that case rests.  For if there is no essential connection between an animal’s locomotive behavior and conscious awareness, then there is certainly no essential connection between the less dramatic, non-locomotive responses of plants to their environments (growing toward the sunlight, etc.) and conscious awareness.

So, there is simply no good argument for awareness in plants.  Those who claim otherwise are, I submit, not thinking about the matter very carefully.  They ignore crucial differences between plants and animals while magnifying superficial similarities.  In this respect their arguments are like those purporting to show that some apes have linguistic abilities comparable to those of small children -- about which Noam Chomsky once aptly said: “That's about like saying that Olympic high jumpers fly better than young birds who've just come out of the egg -- or than most chickens.  These are not serious comparisons.”  

Bottom line: If that weed seems to be “communicating,” that could just be ‘cause you’ve been smokin’ it…

Thứ Tư, 20 tháng 6, 2012

The Spring 2012 issue of Theoretical and Applied Ethics contains a symposium on Ethics, Atheism, and Religion.  The lead essay is by Colin McGinn and is followed by responses from me, Steve Fuller, Ted Peters, and Robert Sinclair.  All the essays can be read online, so go take a look.

Chủ Nhật, 17 tháng 6, 2012

A reader of my recent post on the philosophy of nature asks some excellent questions:

I wonder, where does the philosophy of physics and in general the philosophy of science fall in between the scheme of metaphysics and philosophy of nature?...

Also, where does the discussion on the topic of the laws of nature belong?  Is that also philosophy of nature? 

Let’s start with the question of how the philosophy of science is related to the philosophy of nature.  Recall from my recent post that as the middle ground field of the philosophy of nature gradually disappeared off the radar screen of modern philosophy, the disciplines on either side of it -- on the one hand, metaphysics and on the other, empirical science (in the modern rather than Aristotelian sense of “science”) -- came to seem the only possible avenues of investigation of reality.  Recall also that the methodology of metaphysics came to seem a matter of “conceptual analysis,” while any study with empirical content came to be identified as part of natural science.  The very notion that there could be a middle ground field of study with empirical foundations but arriving at necessary truths, thus transcending the contingent world described by physics, chemistry, etc. and pointing the way to metaphysics -- as Aristotelian philosophy of nature claims to do -- was largely forgotten.

(The Aristotelian theory of act and potency is the classic example of such a piece of middle ground knowledge.  It is grounded in the basic empirical datum, the fact of change.  But it is not a description of this or that particular change or this or that particular kind of change but rather of all change as such.  Hence while empirically grounded it is not subject to falsification by theorizing in physics, chemistry, etc., because the phenomena dealt with in all such theorizing, since they all involve change, implicitly presuppose the theory of act and potency.  When the theory is worked out, though, it points beyond itself to the core theses of metaphysics, including natural theology -- indeed, as I have argued elsewhere, the theory of act and potency is the key to a sound natural theology.  It is no accident that contemporary philosophers who think metaphysics rests on “conceptual analysis” and who suppose the arguments of natural theology are just lame “god of the gaps” inferences have typically never even heardof the theory of act and potency.  As our friend James Chastek once aptly wrote, “a thomist could probably teach the whole history of modern thought as an overlooking of the distinction between potency and act.”  But I digress.)

A further background consideration is that while ancient and medieval philosophy tended to regard questions of ontology as fundamental and questions of epistemology as secondary, early modern philosophy essentially reversed this.  That is to say, the tendency of the ancients and medievals was to start with questions about what sorts of things exist and what their natures are, and then address the question of how we human beings come to have knowledge of the existence and natures of things.  (After all, to answer the latter, epistemological question you first have to know what a human being is, which is an ontological question.)  The early moderns tended to start instead with the question of how we can know anything -- where that question is understood, not the way an Aristotelian would understand it (as a request for an account of how distinctively human cognitive faculties work, etc.) but rather in terms of radical Cartesian doubt -- and only then, after addressing this skeptical question, to address questions of what sorts of things exist and what they are like.  (The bizarreries of rationalist, empiricist, and Kantian epistemology and metaphysics were the inevitable results of this perverse procedure.  But again, I digress.)  

Now, just as the Aristotelian-Scholastic understanding of metaphysics as grounded in the philosophy of nature gave way to the rationalist conception of metaphysics as grounded in innate ideas, which in turn gave way to the idea of metaphysics as “conceptual analysis,” so too did the Cartesian epistemology of the early moderns which had displaced the Aristotelian-Scholastic approach in turn give way to the linguistic emphasis of early twentieth-century analytic philosophy.  But whether framed in terms of rationalist or empiricist “ideas,” or Kantian “categories,” or the “formal languages” of the logical positivists, or the “ordinary language” of Wittgenstein and Ryle, or the various technical or commonsense “conceptual frameworks” of other writers, the result was invariably subjectivist-- philosophy as a kind of higher navel gazing, the study not of reality but of how we know, or conceptualize, or describereality.  

Enter the philosophy of science.  The philosophy of nature is concerned with, well, nature -- with the same objective, material world studied by science, albeit it studies deeper aspects of that world than science does.  The philosophy of science is concerned -- or at least was, for most of its history, primarily concerned -- not with nature, but (no surprise) with science, with the disciplines that study the objective, material, natural world.   That is what it was bound to be concerned with given the developments I’ve described.  For with the virtual disappearance of the philosophy of nature and the reduction of metaphysics to “conceptual analysis” or the like, it came to seem that only empirical science could tell us anything about the natural world itself.  The most philosophy could do was address questions about how we know about or describe that world.  Hence for most of its history the philosophy of science was essentially concerned with questions about the methodology of science, the logical structure of scientific theories, the meaning of scientific assertions, and the like (and also, after Kuhn, Feyerabend, and Lakatos, with the history of science).  In other words, whereas the philosophy of nature (like ancient and medieval philosophy in general) had an ontological focus, the philosophy of science has historically tended (like modern philosophy in general) to have an epistemological(or at least logico-linguistic) focus.  Hence while science looks at the world, the philosophy of science looks at science looking at the world.

Now as I have said, that was true of the discipline for most of its history and for the mostpart.  But not entirely, and not so much these days.  For science, like ordinary experience, simply and unavoidably raises ontological questions it cannot answer.  What is it to be a law of nature?  What is it to be a cause?  Are the theoretical entities posited by physics real?  Are chemistry and biology reducible to physics?  What is a species?  Is science the only avenue of rational investigation of the world, even of the material world?  Philosophers of science were bound to address such questions, and as they addressed them -- and in particular, as they endorsed or at least entertained realist answers to such questions -- work in the philosophy of science started to reflect a concern with issues in what was traditionally known as natural philosophy or the philosophy of nature.  This is especially so in sub-fields like the philosophy of physics, philosophy of chemistry, and philosophy of biology, which are concerned with ontological questions no less than methodological or epistemological issues.  

So, though historically the philosophy of nature and the philosophy of science have tended to have significantly different concerns, recent work in the philosophy of science has included a consideration of issues that have historically been the concern of philosophy of nature.  And some contemporary mainstream writers on the philosophy of science would even go so far as to advocate at least a partial return to the specifically Aristotelian philosophy of nature that the early moderns rejected.  (For more on the Aristotelian understanding of the relationship between the philosophy of nature and the philosophy of science, see William A. Wallace, The Modeling of Nature: Philosophy of Science and Philosophy of Nature in Synthesis.)

While we’re on the subject, it is worth noting that other “Philosophy of…” sub-disciplines also seem to have their origins in the abandonment of the Aristotelian-Scholastic philosophy of nature.  Consider the philosophy of mind.  You won’t find ancient and medieval writers, or later Scholastic writers (well, with the occasional exception), devoting works to that subject.  You willfind works on psychology, but “psychology” as they understood it is not merely the study of the mind.  It is rather the study of the soul, where for Aristotelian-Scholastic writers the soul is the form of a living thing, and where “form” is the principle of actuality correlative to “matter” as the principle of potentiality.  Hence “psychology,” for Aristotelian-Scholastic writers, is just that branch of the philosophy of nature devoted to the study of living things, and brings to bear on that study the main concepts of that more general discipline (act and potency, form and matter, efficient and final causality, etc.).  The study of sensation and imagination is part of the study of animal life specifically; and the study of intellect is part of the study of rational animals (i.e. human beings) even more specifically.  So, the study of “mind” is only a part of psychology, which is itself a branch of the philosophy of nature.

Now when the early moderns chucked out the Aristotelian-Scholastic philosophy of nature, “psychology” was radically transformed.  Gone was the idea that there is an absolute difference in kind -- in particular, a difference in substantial forms and immanent teleological properties -- rather than a difference in degree, between the inorganic and the organic, and between different sorts of inorganic phenomena and different sorts of organic phenomena.  The natural world would come to be reconceived as a vast sea of matter -- “matter” now understood in corpuscularian, atomist, or plenum theoretic terms, and more generally in mathematical terms -- on which tables and chairs, rocks and trees, dogs, cats, and human bodies were, in effect, all just so many waves, the differences between them relatively superficial.  No longer thought of as the substantial form of a living thing, the soul was shrunk down to Descartes’ res cogitans, and the sequel was the modern idea that “psychology” is essentially the study of the mind.  

Now to effect this re-conception of matter, the moderns had to deny that color, odor, sound, taste, heat, cold and sensory qualities in general really existed in the material world in the way common sense supposes they do.  Therein lay the origin of the “qualia problem” -- the problem of explaining exactly how, if these qualities are not really in matter, they are related to the brain, which is one material object among others.  Immanent final causes were also removed from the material world.  And therein lay the origin of the “problem of intentionality” as that is understood in modern philosophy -- the problem of explaining how, if nothing in the material world is inherently “directed toward” anything else as to an end or goal, the directedness of thought relates to the brain.  Features that had once been regarded as inherent to material phenomena in general were suddenly relocated into the mind, which made the mind seem a bizarre exception to what natural science had to say about the rest of nature.  The “philosophy of mind” arose as the discipline concerned with solving this problem.  Cartesian- and property-dualist “solutions” face the interaction problem and the specter of epiphenomenalism; materialist “solutions” tend toward an incoherent eliminativism.  From the Aristotelian-Scholastic point of view, the whole problem -- and by implication the discipline that arose to deal with it -- rests on a mistake.  (See chapter 4 of Aquinasand chapters 5 and 6 of The Last Superstition for more detailed treatment of this subject.)

A friend once asked me why I thought there was in modern philosophy no parallel sub-discipline called the “Philosophy of matter.”  A very good question.  The answer, I think, is that a great many modern philosophers have uncritically swallowed the idea that physical science tells us everything we need to know about matter and that mind alone is problematic, so that a “philosophy of mind” is needed in a way that a “philosophy of matter” is not.  Many, but not all.  Bertrand Russell and contemporary philosophers influenced by him (Michael Lockwood, Grover Maxwell, David Chalmers, Galen Strawson, and others) have emphasized that physics does not in fact give us the intrinsic nature of matter, but only its structure.  Idealists, panpsychists, process philosophers, and neutral monists have offered different accounts of what this intrinsic nature is.  They do not agree with the Aristotelian-Scholastic philosopher about the solution, but at least they recognize the problem.  And there really is no good reason why matter, as the moderns tend to think of it, should be considered any less problematic than mind; indeed, as these various non-materialist modern philosophers tend to realize, it is more problematic.  (It was by reading Russell and Lockwood -- neither of whom is a religious apologist -- that I came to see, while I was in graduate school and still an atheist, just how philosophically problematic the modern conception of matter really is, and how superficial is the thinking of most contemporary materialists.)

It is arguable that even the “Philosophy of religion,” as that discipline is understood today, is an artifact of the moderns’ abandonment of the philosophy of nature.  For the Aristotelian-Scholastic tradition, the theory of act and potency, when worked out, leads us to the existence of a cause of change that is pure actuality, which is the philosophical core of the Aristotelian conception of God.  Other arguments in the philosophy of nature and in metaphysics lead in the same direction.  (See chapter 3 of Aquinas and my ACPQarticle “Existential Inertia and the Five Ways” for more on that subject.)  The upshot is a body of knowledge that constitutes a “science” (in the Aristotelian sense) of its own, namely natural theology.

But as I noted in my earlier post, the main arguments of traditional natural theology were radically transformed (and indeed stripped of their force) as a result of the abandonment of the philosophy of nature.  In particular, they were retooled either as arguments of the Leibnizian rationalist metaphysical sort or as quasi-scientific empirical hypotheses of the Paleyan sort, and thereby made subject to stock objections often regarded as fatal, but in fact irrelevant to the older Aristotelian-Thomistic theistic arguments.  With the virtual disappearance of the philosophy of nature and the deflation of metaphysics, natural theology as a body of knowledge in its own right also disappeared.  In its place came the “Philosophy of religion,” a handful of stand-alone philosophical curiosities rather than (as Scholastic natural theology had been) a vast and systematic body of thought.  The dismissal of grotesque caricatures of the Five Ways would become the order of the day as Aristotelian metaphysics and philosophy of nature, apart from which the arguments cannot be understood, were forgotten.  The Platonic-Augustinian background to Anselm’s ontological argument would also be routinely ignored.  In general, the arguments of classical and medieval authors would be crudely assimilated to those of modern writers like Leibniz, Descartes, and Paley, and thereby misinterpreted either as exercises in rationalist metaphysics grounded in “conceptual analysis,” or as “god of the gaps”-style empirical hypothesis formation.  

There’s more to the story than that, of course.  But that story, like the story of modern philosophy in general, simply cannot be understood unless one understands the role that the philosophy of nature played in ancient and medieval thought, and the gap that was left when it was abandoned.

Chủ Nhật, 10 tháng 6, 2012

When Ray Bradbury was twelve years old, he went to a carnival and encountered Mr. Electrico, a performer who sat in an electric chair with current running through him so that his hair stood up and an electrical sword he held would glow.  Touching the sword to the young Bradbury’s head, Mr. Electrico exclaimed: “Live forever!”  Alas, Mr. Electrico’s command has gone unheeded, for Bradbury died last Tuesday at 91 -- long-lived, to be sure, but well short of forever.

Bradbury’s work has always meant a lot to me.  He was not a hard SFwriter, but serious science fiction need not always be about accurately tracing the implications of current scientific theory and knowledge.  There is also a humanistic side to the genre, which includes the exploration of the unique perspective its unusual situations open up on the nature and motivations of human beings.  At that Bradbury excelled.  And of course, he wrote beautifully and imaginatively. 

Indeed, imagination prevailed over intellect (as an Aristotelian might put it) in the sense that Bradbury was not a systematic thinker.  On the other hand, he was refreshingly resistant to the “smelly little orthodoxies” that prevail in literary circles.  Though more or less a mushy libertarian on what we euphemistically call the “social issues,” Bradbury was in other respects quite conservative.  Recently I was reading Sam Weller’s Listen to the Echoes: The Ray Bradbury Interviews, wherein Bradbury says the following:

Somebody somewhere along the line had the give the taxes back to the people.  Roosevelt never did it, Hoover never did it.  They could have cured the Depression in 1932 when my father was out of work for ten years.  My father suffered.  They should have given him back his tax money.  Nobody thought of that, and nobody did anything.  Kennedy was the first to experiment with it.  The year before he died, there were a few experiments with giving the taxes back, but there was never the chance to really experiment fully, and he died.  So it was never mentioned again until Reagan came along and cut the taxes, and then we began to get jobs.  When he came into office, there were millions of people unemployed.  He lowered taxes all over the United States and created millions of jobs.

About the recent economic crisis, Bradbury said:

We made a lot of mistakes with credit cards, we made a lot of mistakes with mortgages… A lot of people are stupid.  They didn’t pay attention to their expenses.  They had too many credit cards, they spent money without knowing it.

And about the Cold War and the Iraq war:

[Reagan] was one of the best presidents of the last century… [H]e was the first person to have the courage to challenge the Russians to tear down the wall.  Reagan and Pope John Paul II ended the Cold War…

[W]hen President Reagan stood his ground over nuclear disarmament against Gorbachev in Reykjavik, Iceland, it scared Russia.  Gorbachev told me this when I had lunch with him, that Reagan was our best president.  He forced Russia to either spend billions of dollars they didn’t have to keep up the Cold War, or to reconsider negotiating peace…

Had we overthrown Hussein during the first Gulf War, we wouldn’t be in Iraq today.  We blame Bush Two for the war in Iraq, but that was his father’s fault.  But we don’t pay enough attention to the fact that we got rid of a dictator and they have had an election in Iraq.  That’s a good thing.

On matters of religion Bradbury tended toward a vague spirituality.  But while he thought there was little we could know for sure where theology is concerned, he was equally disinclined to accept the dogmas of scientism:

I’m a delicatessen religionist… “Well, how can you believe in Darwin, Lamarck, and Genesis?”  I say, “Because nothing is proven.”  None of it.  So therefore why not have a delicatessen in your head?  I’ll take some of these ideas, some of those and some of that.

Like I said, not a systematic thinker.  But there was a further aspect to his character that made him an especially attractive personality, and something that is a key part of (though of course by no means the whole of) true religion and true conservatism.  As Weller puts it, “Ray lives each day with immense gratitude.”  Not optimism -- though Bradbury certainly had that -- but an attitude of thankfulness for all the good there is in creation.  Many a modern intellectual is constantly pissed off at the world, always on the lookout for something new about which to bitch and moan.  Not Bradbury.  Asked whether it was fame that motivated him to become a writer, Bradbury answered: “Love motivated me.  Love is the answer to everything.  I was in love with life.”

That’s got to count for something when one meets one’s Maker.  RIP.

Thứ Năm, 7 tháng 6, 2012

George Mason University physicist Robert Oerter has completed his series of critical posts on my book The Last Superstition.  I responded to some of his remarks in some earlier posts of my own (hereand here, with some further relevant comments hereand here).  In this post I want to reply to what he says in his most recent remarks about the Aristotelian argument from motion to an Unmoved Mover of the world.

All or some?

The version of the Scholastic principle of causality relevant to the argument from motion holds that any actualized potential must be actualized by something already actual.  A common and more colloquial (but also potentially misleading) formulation would be: Whatever changes must be changed by something else.  Now in one of his most recent posts, Oerter claims that, in the course of defending the argument from motion in The Last Superstition:

Feser abandoned [this principle], and replaced it with something like “Some things that changed [sic] are changed by something else.”  This is fatal to his argument, though…

[Feser’s argument] obviously relies on the idea that everything that changes is being changed by something external to it. If only some things that change require an external changer, then the argument is just a non sequitur. 

Now this is quite bizarre.  Oerter is correct when he says that to abandon the principle of causality and replace it with a weaker premise like “Somethings that change are changed by something else” would undermine the argument.  But in fact I never abandoned the principle and never adopted the weaker alternative principle Oerter attributes to me.  Why does he claim otherwise?

The reason is that Oerter has badly misinterpreted the remarks about Newton’s principle of inertia that I made in the book.  What I said was that even if we allow (at least for the sake of argument) that Newton’s law accounts for local motion (i.e. change of place) of a uniform rectilinear sort, there are still other kinds of change that it would not account for.  Oerter reads this as an affirmation that inertial motion does not have a cause even if other kinds of change do.  But I never said, and would never say, that such motion does not have a cause.  What I said is that even if we allowed that such motion is in some respects “explained” by Newton’s law, (a) there are other kinds of change that the law would not explain, and (b) Newton’s law would not be a completeexplanation even of local motion, both because it does not explain the acquisition or loss of momentum, and because the operation of the law itself stands in need of explanation.  And none of that entails that uniform rectilinear local motion does not have a cause.  

What isthe cause of such motion?  To take a concrete example, what is the cause of the inertial local motion of a stone which someone has thrown into the air?  Well, here’s an answer some Aristotelians would favor.  First of all, on one Aristotelian interpretation of laws of nature, a law is shorthand for a description of the way a thing will operate given its nature or substantial form.  And in the case of inanimate natural phenomena, the efficient cause of their natural operations is whatever generated them and thus gave them their substantial forms.  So, part of the cause of the stone’s inertial motion is whatever natural process brought the stone into existence and thereby imparted to it a substantial form of the sort that entails operation according to the law of inertia.  But that is only a necessary condition of the stone’s inertial motion, since something needs to set it in motion in the first place.  And of course, what set it in motion is whoever threw it into the air.  Hence (on the Aristotelian account in question) the total efficient cause of the current inertial local motion of the stone in question would be the thrower of the stone together with whatever natural processes generated the stone.

Now other Aristotelians have put forward different analyses; and as I have said before, I discuss these issues in greater depth in my article “The medieval principle of motion and the modern principle of inertia,” forthcoming in the Proceedings of the Society for Medieval Logic and Metaphysics.  The point for present purposes is merely to note that there is nothing in Newton’s law that entails that inertial local motion lacks a cause.  And I certainly never claimed that it lacks a cause!

“First” in what sense?

Scholastic writers distinguish between accidentally ordered and essentially ordered causal series.  A stock illustration of the former kind of series is a father who begets a son who in turn begets another.  A stock illustration of the latter sort of series is a hand which uses a stick to move a stone.  The stick in the latter example has no power on its own to push the stone; it moves the stone only insofar as it is being used by the hand as an instrument for moving it.  By contrast, a man who begets a son does have the power to do so inherently, “built in” as it were.  It really is he who begets his son; it is not his own father who does so, using him as an instrument.  (These are, though, merely illustrations intended to jog the ideas in question, and as I explained in a recent post, nothing rides on the precise empirical details.)

Now it is essentially ordered series rather than accidentally ordered series that necessarily have a first member.  But “first” here doesn’t mean “the member that comes at the head of the line, before the second, third, fourth, etc.”  Rather, “first” means “fundamental” or “underived.”  The idea is that a series of instrumental causes – causes that have their causal power only derivatively, only insofar as they act as instruments of something else – must necessarily trace to something that has its causal power in a non-instrumental way, something which can cause without having to be made to cause by something else.  And the argument from motion claims that only that which is pure actuality -- that which is, as it were, “already” fully actual and thus need not (indeed cannot) have been actualized by anything else -- can be causally fundamental or underived in an absolute sense.  

This does not require such a cause to come at the head of some metaphysical queue.  Even if we suppose there to exist a series of instrumental causes that regresses to infinity or loops around in a circle, there would still have to be a “first” cause in the sense of an underived or non-instrumental cause outside the infinite regress or loop, otherwise the infinite or circular series as a whole -- comprised as it is of instrumental causes having no causal power of their own -- could not exist.  As some Thomists have put it, a paintbrush has no power to move itself, and it would remain powerless to move itself even if it had an infinitely long handle.  (I have addressed this issue in an earlier post and in my book Aquinas.  I have also explained in another post that Aquinas does not in fact think that God causes the existence of things through intermediate causes -- talk of such intermediate causes is best read in a “for the sake of argument” way.)

This brings us to another respect in which Oerter’s comments about the argument from motion come to grief.  About essentially ordered causal series, Oerter says:

[T]he idea that causes can be arranged in nice ordered chains as envisioned by Feser just doesn't accord with what we know about the way the universe works…

Think about two masses, A and B, in circular orbits around their common center of mass…

The change in A's velocity is caused by B's gravity, and the change of B's velocity is caused by A's gravity. There's no need for one of these to be causally prior to the other.

Instead of nice ordered chains of causality, there are complex interconnecting webs of interactions. When all the causes are present at once, as they are in the situations Feser calls "essentially ordered chains," no one of them need be considered the "first."

The trouble with this is that it assumes that the Scholastic is arguing for a “first mover” in the sense of a mover coming at the head of a line.  And as I have just explained, that is not what is at issue.  Let a system of causes be as complex as you wish -- an infinite series, a circle, a vast crisscrossing network -- to the extent that they are instrumental in character, there will have to be something outside the system as a whole imparting causality to it.

Causal powers

Oerter raises a more interesting objection when he writes:

[E]verything in the world has the "power of movement in itself"…  Changes, for the physicist, are the result of forces, and forces are part of the nature of those fundamental particles from which everything is made.  It is the nature of massive particles to exert the gravitational force, of charged particles to exert the electromagnetic force, and so on.  So any particle (or collection of particles) can be the "first mover" in the series.

What Oerter doesn’t realize, though, is that (apart from a qualification here or there), this isn’t a criticism of the Aristotelian-Scholastic position; on the contrary, it just is the Aristotelian-Scholastic position!  The notion that material substances operate in the regular ways uncovered by physical science by nature, by virtue of something inherentto them, is the core of the Aristotelian-Scholastic doctrine of substantial form -- the doctrine that the early moderns reacted against and replaced with the notion of matter as something inherently passive.  (As some contemporary philosophers of science and metaphysicians with no Thomistic or theological ax to grind have emphasized -- see the work of Nancy Cartwright, Brian Ellis, and other writers of a broadly “new essentialist” or "dispositional essentialist" sort -- modern science is in fact better interpreted in neo-Aristotelian terms rather than in terms derived from modern post-Cartesian and post-Humean philosophy.  I developed this point at the end of The Last Superstition, which makes it odd that Oerter overlooks it.)

Indeed, for the Aristotelian-Scholastic tradition, living things just are “self-movers” in a loose sense: Unlike a stone (say), a dog, bird, or snake can in an obvious sense move itself toward the realization of the ends toward which its nature points it (food, mating opportunities, etc.).  And while inorganic natural substances don’t move themselves in the same manner, their behavior is nevertheless “spontaneous” in a way the operations of artifacts are not.  (I borrow the term from James A. Weisheipl’s Nature and Motion in the Middle Ages, essential reading on the issues under discussion.)   What that means is, not that their activity is without a cause, but rather that it flows from something immanent or intrinsic to them, from their very nature rather than being imposed from outside.  There is nothing intrinsic to a watch that makes it tell time; that end is imposed on the metal parts by a designer.  But there is, just as Oerter says, something intrinsic to particles by virtue of which they exert gravitational or electromagnetic force.  Now the cause of their doing so is whatever generated them and (thereby) gave them their substantial forms.  Once they exist, though, that activity just follows from their nature.  (This is one reason why Thomists are frequently critical of “Intelligent Design” theory.  To model natural substances on artifacts is precisely to misunderstand them.  See my post on the Aristotelian distinction between “nature” and “art,” and my other posts on the dispute between Aristotelian-Thomistic philosophy and ID.)

All the same, natural substances are not the source of their activity in an absolute and ultimate sense.  For any material substance is a composite of substantial form and prime matter; and since prime matter exists only as actualized by substantial form, while substantial form is a mere abstraction unless instantiated in prime matter, we will have an explanatory vicious circle unless we appeal to something outside the form/matter composite which sustains it in being.  And this can, ultimately, only be that which is purely actual (and thus something for which the same vicious circle cannot arise).  Furthermore, any material substance is a composite of an essence together with an act of existence, and thus in need of something which combines these metaphysical parts if it is to persist in being at any particular instant.  And this can, ultimately, only be something whose essence just is existence, that which is subsistent being itself (and thus something which need not and indeed could not have a cause which combines its essence with a separate act of existence).  I develop these themes at length in my American Catholic Philosophical Quarterlyarticle “Existential Inertia and the Five Ways” (which can be read online by Googling the title, scrolling down to the fourth or fifth result, and clicking on “Quick view”).

Newton again

In a further post on the subject of motion, Oerter (after mistakenly implying yet again that I have “abandoned” the claim that whatever changes is changed by something else) says that in an earlier response to him I had “claim[ed] that inertial motion is not realchange,“ though Oerter also suggests that I am “cagey” about whether this is really what I think.  He then goes on to characterize this view as “a perfect example of the kind of absurdity you get when you don't allow physics to inform your metaphysics.”

But I did not assert that “inertial motion is not real change,” cagily or otherwise.  What I said is that inertial motion is often characterized as a “state” -- by physicists themselves, mind you (which makes it rather odd for Oerter to accuse me of not “allowing physics to inform metaphysics,” but never mind).  And I noted that if inertial motion is a state (and thus not a real change), then there could not be even a prima facie conflict between Newton’s law and the principle of causality.  But I did not claim that this is in fact the correct way to characterize inertial motion.  On the contrary, in the post to which Oerter is responding I also wrote that:

Newton’s law is descriptive.  It tells us how a body behaves, but not why it behaves that way.  Thus the law does not rule out the thesis that the reason a body so behaves is because of a “mover” which actualizes its potencies for motion.  (To be sure, the law does rule out any scenario where a body continues at rest or uniform rectilinear motion while acted upon by physical forces impressed upon it.  But -- to appeal once again to the analogy with Kepler’s laws -- the principle of causality no more requires that what actualizes a potency is, specifically, a physical force of this sort than to affirm a cause of the orbits of the planets requires positing a special kind of massive body additional to the sun, planets, asteroids, etc.)

In other words, I explicitly considered the alternative interpretation of inertial motion on which it involves genuine change, and pointed out that even on that interpretation Newton’s law is not incompatible with the principle of causality.  Now it is true that in the immediate surrounding context of this particular passage I also say that Newton’s law and the principle of causality are not using “motion” in precisely the same sense.  And perhaps that led Oerter mistakenly to conclude that I was assertingthat Newton’s law is not describing genuine change.  But my point was that the principle of causality is talking about anyactualization of potential, while Newton’s law (a) is talking only about local motion specifically and (b) by itself says nothing one way or the other about whether local motion involves the actualization of potential.  And that leaves open the question of whether inertial motion does involve real change.  

Now the reason I did not assert one way or the other whether inertial motion involves real change is that that particular question simply needn’t be settled in order to defend the argument from motion against the charge that it somehow conflicts with Newton’s law.   On eitherinterpretation, the principle of causality is perfectly compatible with Newton’s law.  Indeed, part of my point -- though in fairness to Oerter, this is a point I develop in my book Aquinas (which he has not read) rather than in The Last Superstition -- is that the objection from Newton’s law is not even well-defined in the first place.  It rests on ambiguities any resolution of which leaves the objection without force.  In fact, the burden of proof isn’t on the Thomist to show that his argument is compatible with Newton’s law; the burden is on the critic to show that it is not compatible.  

In particular, to show that there is any conflict, the critic has to explain exactly what it means to characterize inertial motion as a “state”; exactly how inertial motion can amount to real change if it really is a “state”; exactly how Newton’s law could conflict with the principle of causality even in principle if inertial motion does not involve real change; exactly how Newton’s law is incompatible with the principle of causality (and not merely with the influence of physical forces) even if inertial motion does involve real change; exactly what it means to characterize Newton’s principle as a “law” and exactly how the notion of a “law” can be cashed out in a way that doesn’t entail a tacit commitment to the very Aristotelian conception of nature (including substantial forms, etc.) that the argument from motion rests on; and so forth.  And as I argue in Aquinas (and at greater length in the forthcoming article) critics of the principle of causality who appeal to Newton have not done this.  The standard procedure is just glibly to assert that there is a conflict, without bothering to address any of the issues that would have to be worked out before a claim of conflict could be justified

And Oerter adds nothing substantial to the critic’s case.  Instead, he tells us that a better account of motion would, among other things, “declare that velocity doesn't need an explanation (it is something that is just in the nature of massive objects).”  This is quite rich coming from a critic of the Aristotelian-Thomistic position -- A-T writers are, after all, constantly accused (falsely) of trading in pseudo-explanations of the “it’s just in the nature of…” sort!  Of course, no Aristotelian or Thomist would begrudge Oerter an appeal to the “nature” of a thing.  The difference between Oerter and us A-T types, though, is that we would never leaveit at that.  We realize (as Oerter seems not to) that we still need an account of what a nature is and why a thing has the nature it does in the first place.  And those questions lead, for the reasons alluded to above, precisely to the conclusion Oerter wants to avoid -- to the existence of a purely actual cause of a thing’s persistence in being, with the nature (i.e. substantial form) it has, at any given moment.

A purely actual first mover?

In the last few paragraphs of the post in question, Oerter seems to allow that if we are speaking of motion or change in the Aristotelian sense of the actualization of potentials and are thinking in terms of essentially ordered causal series, then we do indeed get to a first mover.  But he claims that this does not yet get us to a purely actual mover.  

But what Oerter fails to see is that any mover that is less than purely actual will, by virtue of being composite (composed of form and matter, or essence and existence) require an actualizing cause outside it, which means that no such mover can truly end the regress of actualizers.  Only what is purely actual could do that even in principle.  Again, I elaborate on all this in “Existential Inertia and the Five Ways” -- which (I emphasize for those who would object to having to buy and read one of my books) is an article rather than a book, and available online.