Scientism is the view that all real knowledge is scientific knowledge—that there is no rational, objective form of inquiry that is not a branch of science. There is at least a whiff of scientism in the thinking of those who dismiss ethical objections to cloning or embryonic stem cell research as inherently “anti-science.” There is considerably more than a whiff of it in the work of New Atheist writers like Richard Dawkins and Christopher Hitchens, who allege that because religion has no scientific foundation (or so they claim) it “therefore” has no rational foundation at all. It is evident even in secular conservative writers like John Derbyshire and Heather MacDonald, whose criticisms of their religious fellow right-wingers are only slightly less condescending than those of Dawkins and co. Indeed, the culture at large seems beholden to an inchoate scientism—“faith” is often pitted against “science” (even by those friendly to the former) as if “science” were synonymous with “reason.”

Despite its adherents’ pose of rationality, scientism has a serious problem: it is either self-refuting or trivial. Take the first horn of this dilemma. The claim that scientism is true is not itself a scientific claim, not something that can be established using scientific methods. Indeed, that science is even a rational form of inquiry (let alone the only rational form of inquiry) is not something that can be established scientifically. For scientific inquiry itself rests on a number of philosophical assumptions: that there is an objective world external to the minds of scientists; that this world is governed by causal regularities; that the human intellect can uncover and accurately describe these regularities; and so forth. Since science presupposes these things, it cannot attempt to justify them without arguing in a circle. And if it cannot even establish that it is a reliable form of inquiry, it can hardly establish that it is the only reliable form. Both tasks would require “getting outside” science altogether and discovering from that extra-scientific vantage point that science conveys an accurate picture of reality—and in the case of scientism, that only science does so.

The rational investigation of the philosophical presuppositions of science has, naturally, traditionally been regarded as the province of philosophy. Nor is it these presuppositions alone that philosophy examines. There is also the question of how to interpret what science tells us about the world. For example, is the world fundamentally comprised of substances or events? What is it to be a “cause”? Is there only one kind? (Aristotle held that there are at least four.) What is the nature of the universals referred to in scientific laws—concepts like quark, electron, atom, and so on—and indeed in language in general? Do they exist over and above the particular things that instantiate them? Scientific findings can shed light on such metaphysical questions, but can never fully answer them. Yet if science must depend upon philosophy both to justify its presuppositions and to interpret its results, the falsity of scientism seems doubly assured. As the conservative philosopher John Kekes (himself a confirmed secularist like Derbyshire and MacDonald) concludes: “Hence philosophy, and not science, is a stronger candidate for being the very paradigm of rationality.”

Here we come to the second horn of the dilemma facing scientism. Its advocate may now insist: if philosophy has this status, it must really be a part of science, since (he continues to maintain, digging in his heels) all rational inquiry is scientific inquiry. The trouble now is that scientism becomes completely trivial, arbitrarily redefining “science” so that it includes anything that could be put forward as evidence against it. Worse, it makes scientism consistent with views that are supposed to be incompatible with it. For example, a line of thought deriving from Aristotle and developed with great sophistication by Thomas Aquinas holds that when we work out what it is for one thing to be the cause of another, we are inexorably led to the existence of an Uncaused Cause outside time and space which continually sustains the causal regularities studied by science, and apart from which they could not in principle exist even for a moment.

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If “scientism” is defined so broadly that it includes (at least in principle) philosophical theology of this kind, then the view becomes completely vacuous. For the whole point of scientism—or so it would seem given the rhetoric of its loudest adherents—was supposed to be to provide a weapon by which fields of inquiry like theology might be dismissed as inherently unscientific and irrational. (Obviously the Uncaused Cause argument for God’s existence is controversial, but it has had, and continues to have, prominent defenders to the present day. For readers who are interested, I explain and defend the argument at length—and show how very badly Dawkins and co. misunderstand it—in my recent books The Last Superstition: A Refutation of the New Atheism and Aquinas.)

Conservatives, more than anyone else, should be wary of the pretensions of scientism, a Procrustean ideology whose pretensions were exposed with particular insight by F. A. Hayek, one of the great heroes of contemporary conservatives (including, perhaps especially, secular conservatives—Hayek himself was an agnostic with no religious ax to grind). In his three-part essay “Scientism and the Study of Society” (reprinted in his book The Counter-Revolution of Science) and his book The Sensory Order, Hayek shows that the project of re-conceiving human nature in particular entirely in terms of the categories of natural science is impossible in principle.

The reason has to do with what Hayek calls the “objectivism” inherent in scientism. Modern science arose in large part out of a practical, political concern—to make men “masters and possessors of nature” (as Descartes put it), and enhance “human utility and power” through the “mechanical arts” or technology (in the words of Francis Bacon). This goal could be realized only by focusing on those aspects of the natural world susceptible of strict prediction and control, and this in turn required a quantitative methodology, so that mathematics would come to be regarded as the language in which the “book of nature” was written (in Galileo’s well-known phrase). And yet our ordinary, everyday experience of the world is qualitative through and through—we perceive colors, sounds, warmth and coolness, purposes and meanings.

How are we to reconcile this commonsense “manifest image” of the world with the quantitative “scientific image” (to borrow philosopher Wilfrid Sellars’ famous distinction)?  The answer is that they cannot be reconciled.  Thus the commonsense, qualitative “manifest image” came to be regarded as a world of mere “appearance,” with the new quantitative “scientific image” alone conveying “reality.”  The former would be re-defined as “subjective” – color, sound, heat, cold, meaning, purpose, and the like, as common sense understands them, exist in the mind alone.  “Objective” reality, revealed by science and described in the language of mathematics, was held to comprise a world of colorless, soundless, meaningless particles in motion.  Or rather, if color, temperature, sound and the like are to be regarded as existing in objective reality, they must be redefined – heat and cold reconceived in terms of molecular motion, color in terms of the reflecting of photons at certain wavelengths, sound in terms of compression waves, and so forth.  What common sense means by “heat,” “cold,” “red,” “green,” “loud,” etc. – the way things feel, look, sound, and so forth in conscious experience – drops out as a mere projection of the mind.  The new method thus ensured that the natural world as studied by science would be quantifiable, predictable, and controllable – precisely by redefining “science” so that nothing that did not fit the method would be allowed to count as “physical,” “material,” or “natural.”  All recalcitrant phenomena would simply be “swept under the rug” of the mind, reinterpreted as part of the mental lens through which we perceive external reality rather than part of external reality itself.

Hayek’s view was that the very nature of objectivism precludes its coherently being applied across –the board to the human mind itself. Since the mind just is the “subjective” realm of so-called “appearances”—the rug under which everything that does not fit the “objectivist” method has been swept—it cannot even in theory be assimilated via quantificational modeling to the material world, as that world has been characterized by physical science. The very nature of scientific understanding, at least as the moderns have defined it, thus entails what Hayek calls a “practical dualism” of mind and matter—a dualism that the objectivist method itself foists upon us, even if we want to deny (as Hayek himself did) that it reflects any genuine metaphysical cleavage between the mental and material worlds.

Any attempt to redefine the mind in “objectivist” terms, characterizing its elements in terms of quantifiable structural relations—an approach Hayek himself sketched out in The Sensory Order—would only open the same problem up again at a higher level, as whatever aspects of the mind that fail to fit this objectivist redefinition simply get kicked up to a second-order realm of mere “appearance” (and to further levels still if the method is applied to the second-order realm). Scientism’s attempt to apply the objectivistic method to the human mind itself thus entails in Hayek’s view a vicious regress, a methodological “chasing of one’s own tail” on to infinity. The result may provide certain insights—Hayek thought so—but it cannot hope to provide complete understanding.

The irony is that the very practice of science itself, which involves the formulation of hypotheses, the weighing of evidence, the invention of technical concepts and vocabularies, the construction of chains of reasoning, and so forth—all mental activities saturated with meaning and purpose—falls on the “subjective,” “manifest image” side of scientism’s divide rather than the “objective,” “scientific image” side. Human thought and action, including the thoughts and actions of scientists, is of its nature irreducible to the meaningless, purposeless motions of particles and the like. Some thinkers committed to scientism realize this, but conclude that the lesson to draw is not that scientism is mistaken, but that human thought and action are themselves fictions. According to this radical position—known as “eliminative materialism” since it entails eliminating the very concept of the mind altogether instead of trying to reduce mind to matter—what is true of human beings is only what can be put in the technical jargon of physics, chemistry, neuroscience and the like. There is no such thing as “thinking,” “believing,” “desiring,” “meaning,” etc.; there is only the firing of neurons, the secretion of hormones, the twitching of muscles, and other such physiological events. While this is definitely a minority position even among materialists, there are those who acknowledge it to be the inevitable consequence of a consistent scientism, and endorse it on that basis. But as Hayek would have predicted, the very attempt to state the position necessarily, but incoherently, makes use of concepts—“science,” “rationality,” “evidence,” “truth,” and so forth—that presuppose exactly what the position denies, viz. the reality of meaning and mind. (I have more to say about the incoherence of eliminative materialism here and here.)

But why would anyone be attracted to such a bizarre and muddleheaded view?  And what should we put in the place of the scientism that leads to it?  I’ll address these questions in part II.

Edward Feser is an Associate Professor of Philosophy at Pasadena City College in Pasadena, CA. His webpage can be found at This is the first article in a two-part series; read the second article here.