Catholic philosopher Ed Feser has published an excellent critique of materialism at the Claremont Review.
The points he makes are valid from a conventional and substantialist viewpoint, though a Buddhist might additionally question whether the very concept of materialism is fundamentally deluded and incoherent (perhaps, in the final analysis there are no such things as things - see later section of this post).
Some quotes from Feser's article...
"Contemporary materialists ... routinely denounce Cartesian dualism, Descartes’s famous bifurcation of the world into mind and matter—or more precisely, into res cogitans or “thinking substance,” and res extensa or “extended substance.” And they do so in the name of science. Yet they remain essentially committed to Descartes’s conception of the material world; indeed, modern science would not have been possible without it. What they forget is that the res cogitans they deplore was necessitated by the res extensa they maintain. Hold onto the latter and you are implicitly committed to the former, whether you like it or not. This is the source of the perpetual failure of materialists to come up with explanations of consciousness, meaning, and morality that are convincing."
"To understand the problem requires going back ... to the beginning. Like Francis Bacon, Descartes wanted to make of modern science an instrument by which we might predict and control natural phenomena and develop new technologies. What he saw more clearly than Bacon was that mathematics was the key to realizing this aim. Hence he adopted a purely quantitative conception of the natural world, treating matter as entirely definable in terms of the geometrical property of extension or spatial dimension. Descartes’s successors would put less emphasis on extension, specifically. But the idea that what is material is what you can capture in the language of mathematics is still with us, as a glance at any physics textbook will show.
Now, where does this leave the qualitative aspects of the world of our experience—colors and sounds, tastes and smells, heat and cold, pain and pleasure? Where does it leave the meanings and purposes we see in the world around us, and the thoughts and choices we find within ourselves? Descartes embraced the obvious implications of the exhaustively “mathematicized” notion of matter he had introduced into Western thought, which the scientific revolution took and ran with. If matter is purely quantitative, and the qualitative features of reality cannot be reduced to the quantitative, then they cannot be material. And if these features don’t really exist in the material world but do exist in the mind’s experience of that world, then the mind itself must not be material.
Hence, Cartesian dualism was by no means a desperate rearguard action against the scientific revolution; on the contrary, it was the logical outcome of the scientific revolution. Matter, on the scientific conception, is comprised of colorless, soundless, odorless, tasteless, meaningless particles in fields of force, governed by mathematical laws which describe how these particles happen to behave, but no purposes for the sake of which they behave. To be sure, we might, when doing physics, redefine certain qualitative features in terms of some quantifiable doppelgänger. Color, for example, can be redefined in terms of a surface’s reflection of light of certain wavelengths. Sound can be redefined in terms of compression waves in the air. But these redefinitions, which even a blind or deaf person can understand, do not capture the way red looks, the way an explosion sounds, and so forth. Color, sound, odor, and taste as we perceive them can—given the scientist’s essentially Cartesian conception of matter—exist only in the conscious experiences of an immaterial mind or res cogitans. Meaning can exist only in this immaterial mind’s thoughts. Purpose can exist only in its volitions."
"...having followed Descartes in defining matter in so thoroughly “mathematicized” a way that irreducibly qualitative features, meanings, and purposes are excluded from it, modern science itself effectively closes off the possibility of a scientific explanation of these features. Thus while materialists are right to complain that Cartesian dualism leaves mind-body interaction obscure, dualists are right to complain that purported materialist explanations in fact ignore, or even implicitly deny, the existence of mind."
"Cartesians and materialists alike are correct to regard modern science as having given us a very penetrating grasp of part of the natural order, namely the part susceptible of analysis in purely quantitative terms. Where they both go wrong is in supposing that modern science gives us the whole of that order."
"It is the way modern science characterizes matter, and not particular gaps in current scientific knowledge as described by Wilson, that leaves us stuck with Descartes’s dualism. Given this characterization, we may find ever more detailed correlations between the mental and the physical, but we will never be able to reduce the mental to the physical. Two celebrated recent books by philosophers—Alex Rosenberg’s The Atheist’s Guide to Reality (2011) and Thomas Nagel’s Mind and Cosmos (2012)—see the problem more clearly than Wilson and other contemporary scientists tend to. Rosenberg’s mad but intellectually honest solution is to conclude that if matter as physics conceives of it is all that exists, mind must really be an illusion. Nagel’s sane but no less intellectually honest solution is to conclude that since mind and matter both exist but mind cannot be assimilated to matter as conceived of by physics, it follows that physics does not give us a complete account of matter. There must in Nagel’s view be more to matter than physics reveals, some additional ingredient that could account for the origin of consciousness, meaning, and value." Read it all here
The Buddhist critique of Cartesianism
While not disagreeing with Ed Feser's analysis of the implications of Cartesian philosophy, as carried to its illogical conclusions by eliminative materialists, a Buddhist might question the ontological primacy of both res cogitans and res extensa, on the grounds that the underlying nature of reality is process and change, rather than stable entities.
Buddhists divide all processes into two categories - mental processes ('nama') and physical/mechanistic processes ('rupa'). Hence nama is the dynamic equivalent of res cogitans, and rupa is the dynamic equivalent of res extensa.
Parallelling Feser's analysis, Buddhists believe that although mental processes and physical processes interact, mental processes are not reducible to physical processes.
According to Buddhism, the basis of reality consists of ever-changing processes rather than static ‘things’ or substances. If any ‘thing’ is analysed in enough depth, and observed over a long enough timescale, it can be seen to be a stage of a dynamic process, rather than a static, stable thing-in-itself.
This becomes obvious when we remember that the universe is itself a process (a continuing expansion from the Big Bang), and so all that it contains are subprocesses of the whole.
Mechanistic processes (which include anything that can be modelled by algorithms) explain the working of all machines including computers, and all the classical laws of science including biology, chemistry, and physics.
In contrast, mental processes consist of irreducible aspects of consciousness that have no mechanistic or algorithmic explanation, for example qualia (qualitative experiences such as pleasure and pain) and intentionality or 'aboutness' (the power of minds to be about, to represent, or to stand for, things, properties and states of affairs). For a more detailed discussion see Buddhist Philosophy
