Not all naturalists would put things that way, because the “special sciences” (i.e. everything other than fundamental physics) make reference to entities that, it is widely acknowledged, cannot be smoothly reduced to collections of particles. Hence for many naturalists, something is real if it can be fitted into the ontology of at least some special science or other, even if not strictly reducible to the particles recognized by fundamental physics. Hence, when philosophers speak of the project of “naturalizing” this or that phenomenon (mind, moral value, or whatever), what they mean is showing that it can be accounted for in terms of the concepts recognized by some science.
The late, great Hilary Putnam made an influential contribution to the project of naturalizing the mind with his version of functionalism. But in his later work he grew highly critical of this project. One example among many would be his essay “Why Reason Can’t Be Naturalized,” which is available in his . To be more precise, what he criticizes in this essay is the view that our capacity for knowledge, specifically, can be naturalized. (In other work, he developed important criticisms of naturalistic theories of other aspects of the mind, such as his own earlier functionalist theory and naturalistic theories of intentionality.)
Putnam’s specific targets in this essay are evolutionary epistemology, Alvin Goldman’s reliabilism, W. V. Quine’s naturalized epistemology – and, most interestingly, cultural relativism, which he perceptively characterizes as a kind of naturalism.
Against evolutionary epistemology, Putnam objects that natural selection favors survival value rather than truth or even rational acceptability, and that there is no essential connection between the former and the latter. A belief could be true or rational and yet be the opposite of conducive to survival, and it could facilitate survival while being false and contrary to canons of rationality. Hence appeal to natural selection cannot suffice to explain our capacity for knowledge. Variations on this sort of objection have been developed by Alvin Plantinga and others, and I have discussed it elsewhere (for example, and ).
The basic idea of reliabilism is that a belief is rational if it was produced by a reliable method for arriving at beliefs. Against this, Putnam deploys the following example. Suppose, he says, that the Dalai Lama is infallible on matters of faith and morals, so that any beliefs accepted on the basis of his authority would be produced by a method that is 100% reliable. Suppose further that one of the beliefs a person adopted this way was the belief that the Dalai Lama is infallible on matters of faith and morals. Obviously, this person’s belief would in that case have been adopted on the basis of circular reasoning. But reliabilism would have to conclude that it is nevertheless rational, because it would have been produced by a reliable method.
Quine’s naturalized epistemology, Putnam says, entails the elimination of all normative notions from the theory of knowledge (even if Quine later resisted this characterization). It abandons considerations about what we are justified in believing, warranted in asserting, have a good reason to think, etc. and simply focuses on how we do in fact happen to come to believe whatever we do. But consistently to eschew normative notions would require also abandoning the notion of truth itself. Hence a consistent naturalized epistemology would have to deny that any position is true, including naturalized epistemology itself.
Naturally, Putnam says much more than this about these views, but most interesting, again, is what he says about cultural relativism. Cultural relativism holds that there are no criteria of truth, justification, rationality, etc. that transcend one’s culture (or one’s language, or one’s historical epoch, or what have you). What is true, justified, rational, etc. relative to one culture’s standards will not be true, justified, rational, etc. relative to another’s. And that is all that can be said. To ask “But which culture’s standards are the right ones?” would presuppose that there is some neutral or objective higher-level standard by reference to which the standards of different cultures could be judged, and that is precisely what the cultural relativist denies. We cannot get outside our cultures and adjudicate between them from some culture-independent point of view. If it seems that we can, that is itself merely because we are looking at things from the point of view of a culture that believes in culture-transcendent standards.
Putnam suggests that this is essentially just another variation on naturalism, even if it is not often recognized as such. He writes:
Cultural relativists are not, in their own eyes, scientistic or ‘physicalistic’. They are likely to view materialism and scientism as just the hang-ups of one particular cultural epoch. If I count them as ‘naturalized epistemologists’ it is because their doctrine is, none the less, a product of the same deference to the claims of nature, the same desire for harmony with the world version of some science, as physicalism. The difference in style and tone is thus explained: the physicalist’s paradigm of science is a hard science, physics (as the term ‘physicalism’ suggests); the cultural relativist’s paradigm is a soft science: anthropology, or linguistics, or psychology, or history, as the case may be. That reason is whatever the norms of the local culture determine it to be is a naturalist view inspired by the social sciences, including history. (p. 235)
Putnam notes that the most important cultural relativists often deny that they are cultural relativists. He cites Richard Rorty and Michel Foucault as examples of thinkers whose views he thinks in fact entail cultural relativism even if they do not characterize them that way.
As Putnam emphasizes, cultural relativism simply cannot be rescued from the charge of incoherence. Even to formulate their thesis, cultural relativists need, as it were, to stand outside the perspective of all cultures and claim to observe that there is no culture-transcendent perspective outside of them – which is, needless to say, a self-contradictory exercise. Or if they consistently eschew such a culture-independent perspective, they will have to conclude that cultural relativism itself is nothing more than the expression of the cultural relativist’s own parochial perspective, which no one else has any reason to take seriously.
Putnam takes relativism to be “a far more dangerous cultural tendency than materialism” (p. 235). Neither view can account for knowledge and rationality, but materialism at least tends to pay lip service to them. Cultural relativism, by contrast, reflects a “deep irrationalism,” and also encourages a frivolous intellectual mindset according to which “the deep questions of philosophy are not deep at all… that philosophy, as traditionally understood, is a silly enterprise” (pp. 235-36). This is inevitable given that philosophy is ultimately concerned precisely with the objective standards of truth and rationality that relativism rejects.
Developing the point that relativism is incoherent, Putnam notes an interesting parallel with methodological solipsism. This approach (associated, for example, with Rudolf Carnap’s Der logische Aufbau der Welt) analyzes all reality into constructions out of one’s own experiences. For example, tables, chairs, rocks, and trees are on this view nothing more than collections of the experiences I have of these things. This might sound like solipsism full stop – the view that I and my experiences are all that really exist – but the difference is that the methodological solipsist holds that each of us can carry out the same analysis for ourselves, which implies that there are subjects of experience other than oneself.
The trouble, Putnam notes, is that this is incoherent. If I regard everything as a construction out of my experiences, then it follows that all other people and their experiences are merely constructions out of my experiences. For example, you are nothing more than a construction out of my perceptual experiences of your body, and your experiences are nothing more than a construction out of my perceptual experiences of you talking about your experiences, behaving in certain ways, and so on. Hence there really are no other subjects of experience, when the view is worked out consistently. Methodological solipsism collapses into solipsism full stop.
Now something analogous is true of cultural relativism, as Putnam argues. At first it seems as if the cultural relativist recognizes a plurality of cultural perspectives and regards them all as equally valid. But this is an illusion. For if there are no criteria of truth, justification, rationality, etc. over and above cultural perspectives, then to be consistent, the cultural relativist must regard the criteria of truth, justification, rationality, etc. that characterize his own cultural perspective as the only genuine criteria there are. For if he is consistent, he will have to hold that he can no more transcend his own perspective than anyone else can. To be sure, he will note that others have different perspectives, but he will have to regard them as simply mistaken perspectives, because they conflict with his own perspective and, again, he can have no criteria for truth, justification, rationality, etc. other than his own.
In this way, Putnam concludes, just as methodological solipsism collapses into solipsism without qualification, cultural relativism collapses into cultural imperialism. The cultural relativist must regard his own perspective as the only correct perspective. Hence he is not really a relativist at all.
Putnam notes that there are two opposite extreme errors to be avoided vis-à-vis the relationship between reason and culture, and both neglect the fact that reason is immanent to culture in one respect while transcending it in another. On the one hand, there are those who have too simplistic and exaggerated a view of the independence of reason from contingent cultural and historical circumstances. Putnam cites logical positivism as an example. But the cultural relativist goes to the opposite extreme of entirely submerging reason in culture and historical circumstance. The boring but sober middle ground position is that while our rationality is always exercised in ways that reflect concrete cultural and historical circumstances, it can nevertheless stand back from them and evaluate them critically by reference to criteria that transcend those circumstances. We cannot coherently deny this.
Though Putnam does not note it, there is a parallel here to the Aristotelian conception of the human intellect and its relationship to our bodily nature. On the one hand, the Aristotelian rejects the Platonic-Cartesian view that the mind is radically independent of the body, and its concepts built into it independently of experience of the concrete natural world. Rather, there is nothing in the intellect without prior sensory experience, and even after the intellect is furnished by experience it continually needs the assistance of sensation and mental imagery even when entertaining the most abstract notions. On the other hand, the Aristotelian rejects the materialist view that human beings are entirely corporeal. The formation of concepts involves a kind of dematerialization of the mind’s objects, stripping form entirely out of its concrete material embodiment and considering it in isolation. And the intellect can do this precisely because it is itself an immaterial power.
Though Putnam has himself emphasized the way that the abandonment of the Aristotelian-Scholastic conception of the mind’s relationship to the world poses problems for modern theories of mind, he has also stopped short of advocating a return to it. But one of its advantages is precisely that it accounts for how reason can be both immanent to and transcendent of culture and history in the ways Putnam has noted.