UC Berkeley philosopher (and atheist) Alva Noë is, as we saw not too long ago, among the more perceptive and interesting critics of Thomas Nagel’s Mind and Cosmos. In a recent brief follow-up post, Noë revisits the controversy over Nagel’s book, focusing on the question of the origin of life. Endorsing some remarks made by philosopher of biology Peter Godfrey-Smith, Noë holds that while we have a good idea of how species originate, there is no plausible existing scientific explanation of how life arose in the first place:
This is probably not, I would say, due to the fact that the relevant events happened a long time ago. Our problem isn't merely historical in nature, that is. If that were all that was at stake, then we might expect that, now at least, we would be able to make life in a test tube. But we can't do that. We don't know how.
But it is worse than that, in Noë’s view. He holds that we also do not even know whether such an explanation is just around the corner, or instead will require a scientific revolution, or, alternatively, will turn out to be impossible in principle.
Something similar can be said, in his view, of the question of whether science can explain intelligence:
If we really understood what makes a person intelligent, then it ought to be relatively straight forward, at least in principle, to manufacture intelligence. Some people believe that this is possible. Others that we can actually make intelligent machines and robots now. I do not suppose that they are wrong. But I do take it as manifest that we do not know this to be the case. Many mainstream scientists and philosophers believe that true artificial intelligence is at best unfinished business.
With respect to both controversies -- the origin of life and the nature of intelligence -- Noë writes:
What kind of disagreement is this? To my mind it is foolish to cast it as a standoff between those who embrace science and admit its stunning achievements and those who reject the project of natural science itself. It is not a conflict between those who know and those who are confused. Some critics of Nagel's book adopt this pose, as if this were some kind of episode in our culture wars…
The issue at stake is internal to science. We have not yet integrated an account of ourselves into our understanding of nature. And so our conception of nature itself is, or threatens to be, incomplete.
End quote. In my earlier post on Noë I noted that he also holds that “we haven't a clue” how “consciousness [emerges] from the behavior of mere matter.” The issue here, of course, concerns what David Chalmers calls the “hard problem” of consciousness -- the problem of explaining why the neural processes that underlie perception, behavior, etc., are associated with qualia, those aspects of a conscious experience directly knowable only from the subjective or “first person” point of view.
Life, consciousness, intelligence -- is there anything significant about that particular triad? There is. It corresponds more or less exactly to the traditional Aristotelian distinction between the three fundamental forms of life: vegetative, sensory, and rational.
“Vegetative” life as Aristotelians use that term -- and it is a technical, metaphysical usage, which is not meant to correspond exactly to the way the term is used is ordinary language or contemporary biology -- is any sort of life that exhibits the basic functions of life but nothing more. Those basic functions include nutrition, growth, and reproduction, where these are taken to be “immanent” activities in the sense that they terminate in and promote the flourishing of the whole substance that carries them out. “Immanent” causation is in this context contrasted by Aristotelians with “transeunt” or “transient” casual processes, which terminate outside the agent. Digestion would be an example of an immanent causal process; one billiard ball causing another to move would be an example of a transeunt causal process. For Aristotelians, the essential difference between living and non-living things is that living things are capable of both immanent and transeunt causation, whereas non-living things exhibit only transeunt causation. And nutrition, growth, and reproduction constitute the basic package of immanent activities.
(I say more about this at pp. 132-138 of Aquinasand in some earlier posts about the nature and origins of life, here, here, and here. For a lengthier recent defense of the Aristotelian account of the nature of life, see David Oderberg’s Real Essentialism.)
Sensory life is the sort had by living things that not only carry out the activities characteristic of “vegetative” life, but, on top of that, possess sensation, appetite, and locomotion. Sensation involves the capacity to take in information from the surrounding environment via specialized organs (such as eyes, ears, skin that is sensitive to temperature, and the like). Appetite involves the formation of inner impulses in response to what is sensed, and locomotion involves self-movement that is prompted by the appetitive impulses so as to take the living thing that has them either toward or away from the sensed objects that generated the appetites in question. This package of capacities is, on the traditional Aristotelian view, essentially what distinguishes animals from plants, though there could of course be debate over whether some particular living thing is best understood as falling into the “vegetative” or the “sensory” category (see Oderberg for discussion). But that the distinction between vegetative and sensory forms of life really is a distinction in kind and not degree is evidenced by the persistence of the qualia problem. For the possession of qualia is an essential part of what it is to have the sensory and appetitive capacities that animals exhibit and plants evidently do not. (I’ve said more about this distinction hereand here.)
Rational life, as Aristotelians understand it, is the kind had by living things that possess not only the characteristics typical of vegetative and sensory life -- nutrition, growth, reproduction, sensation, appetite, and locomotion -- but, on top of that, intellect and will. Intellect involves the ability to grasp abstract concepts (such as the concepts man and mortal), to put them together into complete thoughts or judgments (such as the judgment that All men are mortal), and to reason from one judgment to another in accordance with logical principles (as we do when we reason from the premises that All men are mortal and Socrates is a man to the conclusion that Socrates is mortal). Behavior that results from will or free choice is behavior that follows from reason rather than merely from the impulses of appetite.
The Aristotelian holds that, just as sensory life differs in kind and not merely degree from merely vegetative life, so too does truly intellectual activity differ in kind and not merely degree from the sort of which mere sensory forms of life are capable. Indeed, the divide between the truly rational and the merely sensory forms of life is especially radical insofar as strictly intellectual activity (unlike sensory activity) is essentially incorporeal and cannot in principle be entirely reduced to the activity of any bodily organ. I’ve discussed the reasons in many places, such as in Aquinas, but the most detailed treatment can be found in my new ACPQ article “Kripke, Ross, and the Immaterial Aspects of Thought.”
For the Aristotelian, then, there are three radical “jumps” in nature -- the jump from inorganic phenomena to the basic, “vegetative” forms of life (i.e. the sort that exhibit the basic package of “immanent” as opposed to merely “transeunt” activities); the jump from merely “vegetative” forms of life to sensory forms of life (i.e. the sort that possess qualia); and the jump from merely sensory forms of life to rational forms of life (i.e. those with the strictly intellectual capacities that presuppose the possession of abstract concepts). When I speak of a “jump,” though, it is important to emphasize that what I primarily have in mind is something ontological rather than temporal. For the Aristotelian, questions of metaphysics (what a thing is) are more fundamental than, and to be settled prior to, questions of historical origin (where a thing came from). Indeed, at least where we have no independent evidence of origins, we cannot fruitfully address the question of where a thing came from before settling the question of what it is, since only when we know its nature will we know what its possible sources might be.
It is thus sheer, question-begging dogmatism for naturalists to insist that some phenomenon P -- where P is life, say, or intelligence -- simply “must” be purely material because we “know” P could only have had material origins. If we have no direct evidence whatsoever of P’s origins (as is the case with life and intelligence, since no one has ever observed living things arising from entirely inorganic causes, or an intelligent creature arising from entirely non-intelligent causes), then we have to look to P’s nature to begin our investigation of what its causes might have been. And if an investigation of its nature shows that it is not entirely material -- as an investigation of the nature of intelligence shows that it cannot be entirely material even in principle (again, see the ACPQ article referred to above) -- then we know that its causes cannot have been entirely material.
How, then, does the Aristotelian position relate to evolution? The answer is complicated. On the one hand, the Aristotelian obviously rejects the materialist conception of matter associated with contemporary naturalism -- a conception on which the material world is devoid of any immanent teleology or immanent natures (i.e. final causes and substantial forms). On the other hand, nothing that has been said above has anything to do with “specified complexity,” probabilities, “gods of the gaps,” or any of the other themes of “Intelligent Design” theory and William Paley-style design arguments. On the contrary, Aristotelians and Thomists are often extremely critical of ID and of Paley (as I have been in a series of posts). And part of the reason is that ID is simply not radical enough in its critique of naturalism, but implicitly buys into the same false conception of nature to which the materialist is committed, and thereby merely muddies the conceptual waters.
Moreover, modern Aristotelians (such as the Neo-Scholastic writers of the early twentieth century) are not necessarily opposed to evolutionary explanations as such. They do agree, though, that such explanations have limits, and would by no means give a blank check to Darwinian naturalism. And those limits are limits in principle (not mere matters of “probability”) because they have to do with metaphysical divisions in nature (not mere differences in the degree of “complexity” of the arrangement of mechanical parts or the like). I have discussed the Aristotelian-Thomistic approach to the origins of life here, and the question of human origins hereand here.
In any event, it is certainly telling that, although it is part of the modern conventional wisdom that the traditional Aristotelian distinction between vegetative, sensory, and rational forms of life is a historical relic, we have a mainstream, atheist philosopher like Alva Noë essentially admitting that the explanation of each of these forms of life in terms of something more basic is, even in AD 2013, still highly problematic. And as I pointed out in my First Things review of Mind and Cosmos, Nagel -- another mainstream atheist philosopher -- essentially says the same thing about each of these traditional Aristotelian categories. Various other prominent contemporary atheists and naturalists -- Jerry Fodor, John Searle, David Chalmers, and many others -- have acknowledged that at least one or two of these categories remain problematic. And of course, as I noted in an earlier post on Nagel, renewed interest in Aristotelian themes can be found in much contemporary mainstream work in other contexts, such as metaphysics, philosophy of science, and ethics.
Could someone not self-consciously Aristotelian or Thomist sound more Aristotelian than Noë already does? Turns out he can. Consider some remarks he made in the interview linked to above:
For a long time now, going back at least to Descartes and Galileo, we’ve liked to be told that things are not what they seem. When we go to a magic show, there’s a feeling of delicious pleasure when the wool has been pulled over our eyes. Similarly, to be told that the love you feel is actually just a chemical reaction, or that your depression is just a malfunctioning of your brain, is surprising and in some paradoxical way satisfying. There’s a modern pleasure in the unmasking of our everyday experience. We feel like we’re seeing behind the curtain, seeing how the trick is done…
Galileo said that the apple in your hand is colorless, odorless and flavorless. That color and so on are effects that the apple has on you, comparable to the sensation of the prick of a pin. The flavor of the apple, he said, is no more in the apple than the prickliness is in the pin. The taste and the prickliness are in you. Galileo thought we were radically deceived by the world around us. The contemporary neuroscientists simply extend this even further — this idea that the world is a kind of grand illusion that the brain creates.
Sure, it’s an important fact that the perception of colors depends on the physics of light and the nature of the nervous system. If our physiology were different, our ability to detect colors would be different. But none of that speaks to the unreality of color, any more than saying that I can’t see anything in my room if I turn the lights off speaks to the unreality of my desk. We’ve almost made a fetish of this desire to be told that things are not what they seem. We get a thrill from the paradox.
End quote. Noë is particularly critical of reductionist accounts of human nature:
Trying to understand consciousness in neural terms alone is like trying to understand a car driving down the road only in terms of its engine. It’s bad philosophy masquerading as science…
The brain is necessary for consciousness. Of course! Just as an engine is necessary in a car. But an engine doesn’t “give rise” to driving; driving isn’t something that happens inside the engine. The engine contributes to the car’s ability to drive. Consciousness is more like driving than our philosophical tradition leads us to expect. To be conscious is to have a world. The fact is, you and I don’t have what it takes to make a world on our own. We find the world, we don’t make it in our brains.
The brain is essential for our lives, physiology, health and experience. But the idea that it is the whole story, or even the key to understanding the story, is not a scientific conclusion. It’s a prejudice. Consciousness requires the joint operation of the brain, the body and the world.
End quote. What Noë is here decrying is, essentially, what I have described elsewhere as scientism’stendency to reify abstractions and to treat parts of substances as if they were substances in their own right, and his examples are more or less the same as the ones I gave there. From the rich, concrete world of material objects presented to us in experience, which is characterized by colors, sounds, odors, flavors, warmth, coolness, meanings and purposes, causal powers and liabilities, physics abstracts out its mathematical structure. That is extremely useful for certain purposes and certainly captures aspects of what is really out there in the world. But scientism treats this abstraction as if it were the concrete reality itself, and the entirety of that reality. From concrete human beings, neuroscience abstracts out the nervous system and makes of it the focus of study. This too is useful for certain purposes, and is unproblematic as long as it is kept in mind that neural structures and processes can properly be understood only by reference to the whole organism of which they are a part. Scientism, however, fallaciously tends to treat such structures and processes as if they were substances in their own right, and attributes to them activities -- “interpreting,” “perceiving,” “deciding,” etc. -- that can intelligibly be attributed only to the human being as a whole and not to any part, not even a neurological part. (I’ve discussed various “neurofallacies” at greater length hereand here.)
Scientism claims to be “reality based” but that is precisely what it is not. It recognizes only aspects of reality, and in particular only those susceptible of study via its favored methods. When those methods fail to capture some aspect of reality -- God, consciousness, intentionality, free will, selfhood, moral value, and so on -- scientism tends to blame reality rather than its methods, and to insist that the reality either be redefined so as to make it compatible with its methods, or eliminated entirely.
The Aristotelian, by contrast, insists upon recognizing the world as it really is, and adjusting method to reality rather than reality to method. Hence while the methods appropriate to physics -- the construction of mathematical models that capture those aspects of material nature susceptible of strict prediction and control -- are certainly suitable for the study of some phenomena, they are not suitable for biology, psychology, ethics, metaphysics, or what have you.
As we’ve seen, in his most recent post, Noë writes:
The issue at stake is internal to science. We have not yet integrated an account of ourselves into our understanding of nature. And so our conception of nature itself is, or threatens to be, incomplete.
But the Aristotelian-Scholastic tradition had an account that integrated us into nature. It is scientism, which abstracts out of nature everything that smacks of the human, that has created the problem of reintegrating us into it. The solution is not a further application of its methods, which simply compounds the problem, but a realization that those methods are not the only ones available to us, and never were. The work of Nagel, Noë, and Co. is evidence that that realization is increasingly to be found outside the circle of self-consciously Aristotelian and Thomistic philosophers.
