After materialism?

The Naturalist Ideology

It is not so often that a philosophy book is the subject of a debate in widely circulated journals, daily newspapers in the United States (and their websites). This was the case for The Mind and the Cosmos by T. Nagel, when it was published in 2012 by Oxford University Press. Certainly, T. Nagel is one of the most important contemporary American philosophers, a professor at New York University – several of his books have been translated into many languages, including French. But it is above all that, in his latest work, he contests the validity of what he calls a ” Worldview naturalist” (p. 10). If the German term used means “world view”, is it not also possible to translate it as “ideology”? It consists in thinking that the natural sciences constitute the horizon of any correct, that is to say scientific, explanation of the world. They were constituted at the time of the scientific revolution in XVII^e century and with Darwinian theory of evolution in XIX^e century. To be explicable is to be in the terms of physical sciences and neo-Darwinian theory.

The materialist conception of nature is thus the presupposition of scientific explanation today; in the physical sciences, biology, neuroscience, cognitive sciences, this is almost self-evident for most, but also in the human and social sciences, even in aesthetics, in art criticism or in the theory of literature. Man should not therefore be considered an exception in nature. His intellectual and cultural life should itself be explained on materialist epistemological bases. However, says T. Nagel, “the neo-Darwinian materialist conception of nature is very probably wrong” (this is even the subtitle of the book).

It would have been surprising if such a statement had not provoked some outcry. It did not fail to do so.

The sacrosanct reductive program of research

Why did T. Nagel’s thesis make headlines? Because, if we follow him, the thesis according to which a rational explanation is always a reduction to a physical or material explanation is the “sacrosanct program of research with the idea that it alone is scientific.” Now, three phenomena, he says, are neither explained nor explicable within the orthodox framework of the physical and human sciences: consciousness, knowledge and value. This is because they are irreducible to strictly material phenomena. The phenomena characteristic of the life of the mind – thought, intentionality, understanding, apprehension of values ​​- do not emerge from matter; and therefore any science presupposing a form of materialism cannot hope to explain without eliminating them. Consequently, we must “abandon materialism” (p. 65).

But should we consider that the mind is irreducible to matter? Is there even any sense in saying that the mind exists? After all, materialism consists precisely in refusing an opposition between matter and mind, by saying that a good explanation of the latter must be done in terms of the former. Against this thesis, T. Nagel appeals to “common sense” (for example, p. 47), that is to say to the idea that we have of ourselves. No matter what we do, we cannot think of ourselves as simply material things. And finally, ordinary scientific practice does not suppose this either. For “most scientists can work without having an opinion on the general questions of fundamental cosmology” (p. 10), those to which materialist reductionism intends to provide an answer. The progress of science, in the neurosciences for example, credited with great explanatory feats, leaves aside the awareness that we have of ourselves, the understanding of our capacity to understand, including by and in scientific activity. They also leave aside the value that we attribute to certain attitudes when we praise them, by blaming others – basically, good and evil. This is effective in satisfying the requirements of materialist naturalism; it is very little so if we want to understand consciousness, knowledge and our attachment to certain values ​​judged to be real. We should mourn a human exception; the rationality identified with materialism comes at this price.

For T. Nagel, rationality and science are not called into question by his argument, but only the thesis that materialism is the only serious or rational scientific possibility. To resist this assertion is, for common sense, to regain confidence in our “ordinary judgments” (p. 47).

T. Nagel notes that if one types “3”, “+”, “5” and “=” into a pocket calculator, the causal explanation of the shape that appears on the screen – the process that leads to “8” appearing – does nothing to explain why it is the Good answer. Now, in contemporary culture and among its scientific elite, the dominant conviction has arisen that this description of a material process would be the norm for any explanation. This is how materialist naturalism, which is not a scientific theory, has become a conception of the world.

The return of finalism?

But does this not encourage a return to metaphysical and theological explanations, abandoned with the scientific revolution? XVII^e century, and definitively evacuated with neo-Darwinism? We are not going to return to final causes and divine intention, are we? T. Nagel wants to reassure his readers: the hypothesis that biological evolution is at the origin of the existence of conscious phenomena is not rejected. But it is insufficient and even misleading when it comes to explaining the phenomena specific to the mind. And even if, for T. Nagel, “the interest of theism, even for an atheist, is that it tries to explain in another way what physical science does not seem capable of explaining” (p. 37), he nevertheless insistently distances himself from a “probability of theism”.

One objection to him, however, is that this “other way” remains very mysterious in his book. By being neither reductionist nor theist, one leaves the principles of the proposed explanation very undetermined. If the go destroy of the book is clear, its go build is much more vague. However, a good part of the book proposes non-materialist explanations of the mind, knowledge and value, without ever hiding the difficulties. Should we move towards panpsychism, according to which all the elements of the physical world are also mental? Should we integrate an indispensable finalism into our explanations of conscious phenomena? T. Nagel seriously considers renewing “the Aristotelian conception of nature” (p. 101), as a possibility of a non-intentional (since non-theistic) teleology. In the chapter IV of the book, he presents it as particularly appropriate for justifying a realistic theory of moral values ​​(according to which there are moral facts), which for him corresponds to common sense.

The argument from reason

T. Nagel repeatedly takes up, in several forms, an argument that he never names. Let us speak of an “argument from reason”. It consists in saying, according to T. Nagel’s formulation, “that any evolutionary explanation of the place of reason presupposes the validity of reason and cannot confirm it without circularity” (p. 121). We cannot understand evolution, nor any reasoning, without presupposing rationality, which materialist naturalism nevertheless claims is explicable in terms of material processes, or even that it is nothing other than a type of material process. An evolutionary naturalist, someone for whom everything is reducible to states of matter and who claims that his own cognitive system is the product of evolution, therefore has very little reason to have confidence in his cognitive faculties, in his capacity to arrive at having true beliefs.

Thus, the reliability of our rational capacities—without which our best science would hardly be possible—presupposes a principle that is not material. Another way of putting it is that “one cannot really understand the scientific worldview unless one assumes that the intelligibility of the world, as described by the laws that science has discovered, is itself part of the deeper explanation of why things are as they are” (p. 30). Reason cannot be an afterthought to physical processes whose explanatory character cannot be understood without it. Science as we practice, then, does not explain the intelligibility of the world; it presupposes it. Evolutionary naturalism destroys itself if it cannot explain the rational reliability of the knowledge it claims to be.

The connection between knowledge, reason and truth has no naturalistic (in the material sense) explanation. Making truth and reason the norms of your intellectual life makes the physical sciences epistemologically possible, but it cannot be explained in terms of the physical sciences. There is a space of reasons irreducible to the physical world. That beings are capable of understanding, and especially scientifically, the world in which they are, therefore makes them very exceptional in physical nature.

For T. Nagel, “it is particularly up to philosophy to study the limits of contemporary scientific knowledge, even in its most elaborate and fruitful forms” (p. 9). Thomas Nagel thus maintains that philosophical reflection is able to seriously question an attitude presented as scientific, and even falsely identified with scientific thought, materialist naturalism. Thomas Nagel’s book thus helps to identify in the life of science – that of our research institutions, universities, but also in the media treatment of young sciences presented as promising: neuroscience, cognitive sciences, but also the human and social sciences – the materialist presupposition. It is probably false.

It is understandable that such a statement and the general argument of the book could have excited the intellectual world to this extent, in the United States, but also in other countries. It is to be hoped that, starting from this book, it will also be discussed in our skies, where perhaps what T. Nagel calls the “right-thinking consensus” (p. 187) also reigns.