By Massimo Pigliucci

Science is unquestionably the most powerful approach humanity has developed so far to the understanding of the natural world. There is little point in arguing about the spectacular successes of fundamental physics, evolutionary and molecular biology, and countless other fields of scientific inquiry. Indeed, if you do, you risk to quickly slide into self-contradictory epistemic relativism or even downright pseudoscience.

That said, there is a pernicious and increasingly influential strand of thought these days — normally referred to as “scientism” — which is not only a threat to every other discipline, including philosophy, but risks undermining the credibility of science itself. In these days of crisis in the humanities, as well as in the social sciences, it is crucial to distinguish valid from ill-founded criticism of any academic effort, revisiting once more what C.P. Snow famously referred to as the divide between “the two cultures.”

First off, what is scientism, exactly? Sometimes it pays to go back to the basics, in this case to the Merriam-Webster concise definition: “An exaggerated trust in the efficacy of the methods of natural science applied to all areas of investigation (as in philosophy, the social sciences, and the humanities).” But surely this is a straw man. Who really fits that description? Plenty of prominent and influential people, as it turns out. Let me give you a few examples:

Author Sam Harris, when he argues that science can by itself provide answers to moral questions and that philosophy is not needed. (e.g., “Many of my critics fault me for not engaging more directly with the academic literature on moral philosophy … I am convinced that every appearance of terms like ‘metaethics,’ ‘deontology,’ [etc.] … directly increases the amount of boredom in the universe.”)

Science popularizer Neil deGrasse Tyson (and physicists Lawrence Krauss and Stephen Hawking, science educator Bill Nye, among others), when he declares philosophy useless to science (or “dead,” in the case of Hawking). (e.g., “My concern here is that the philosophers believe they are actually asking deep questions about nature. And to the scientist it’s, what are you doing? Why are you concerning yourself with the meaning of meaning?” —N. deGrasse Tyson; also: “I think therefore I am. What if you don’t think about it? You don’t exist anymore? You probably still exist.” —B. Nye).

Any number of neuroscientists when they seem to believe that “your brain on X” provides the ultimate explanation for whatever X happens to be.

Science popularizer Richard Dawkins, when he says “science” disproves the existence of God (while deploying what he apparently does not realize are philosophical arguments informed by science).

A number of evolutionary psychologists (though not all of them!) when they make claims that go well beyond the epistemic warrant of the evidence they provide. Literature scholars (and biologists like E.O. Wilson) when they think that an evolutionary, data-driven approach tells us much that is insightful about, say, Jane Austen.

The list could go on, for quite a bit. Of course, we could have reasonable discussions about any individual entry above, but I think the general pattern is clear enough. Scientism is explicitly advocated by a good number of scientists (predictably), and even some philosophers. A common line of defense is that the term should not even be used because it is just a quick way for purveyors of fuzzy religious and pseudoscientific ideas to dismiss anyone who looks critically at their claims.

This is certainly the case. But it is no different from the misuse of other words, such as “pseudoscience” itself, or “skepticism” (in the modern sense of a critical analysis of potentially unfounded claims). Still, few people would reasonably argue that we should stop using a perfectly valid word just because it is abused by ideologically driven groups. If that were being the case, the next version of the Merriam-Webster would be pretty thin…

Philosopher of science Susan Haack has proposed an influential list of six signs of scientistic thinking, which — with some caveats and modifications — can be usefully deployed in the context of this discussion.

The first sign is when words like “science” and “scientific” are used uncritically as honorific terms of epistemic praise. For instance, in advertisement: “9 out of 10 dentists recommend brand X.” More ominously, when ethically and scientifically ill-founded notions, such as eugenics, gain a foothold in society because they are presented as “science.” Let us not forget that between 1907 and 1963, 64,000 American citizens were forcibly sterilized because of eugenic laws.

The second of Haack’s signs is the adoption of the manners and terminology of science regardless of whether they are useful or not. My favorite example is a famous paper published in 2005 in American Psychologist by Barbara Fredrickson and Marcial Losada. They claimed — “scientific” data in hand — that the ratio of positive to negative emotions necessary for human flourishing is exactly 2.9013 to 1. Such precision ought to be suspicious at face value, even setting aside that the whole notion of the existence of an ideal, universal ratio of positive to negative emotions is questionable in the first place. Sure enough, a few years later, Nicholas Brown, Alan Sokal, and Harris Friedman published a scathing rebuttal of the Fredrickson-Losada paper, tellingly entitled “The complex dynamics of wishful thinking: The critical positivity ratio.” Unfortunately, the original paper is still far more cited than the rebuttal.

Third, scientistically-oriented people tend to display an obsession with demarcating science from pseudoscience. Here I think Haack is only partially correct, as my observation is rather that scientistic thinking results in an expansion of the very concept of “science”, almost making it equivalent with rationality itself. It is only as a byproduct that pseudoscience is demarcated from science, and moreover, a lot of philosophy and other humanistic disciplines tend to be cast as “pseudoscience” if they somehow dare assert even a partial independence from the natural sciences. This, of course, is nothing new, and amounts to a 21st century (rather naive) version of logical positivism:

The criterion which we use to test the genuineness of apparent statements of fact is the criterion of verifiability. We say that a sentence is factually significant to any given person, if, and only if, he knows how to verify the proposition which it purports to express — that is, if he knows what observations would lead him, under certain conditions, to accept the proposition as true, or reject it as being false. — A.J. Ayer (Language, Truth, and Logic)

The fourth sign of scientism has to do with a preoccupation with identifying a scientific method to demarcate science from other activities. A good number of scientists, especially those writing for the general public, seem blissfully unaware of decades of philosophical scholarship questioning the very idea of the scientific method. When we use that term, do we refer to inductivism, deductivism, adbuctivism, Bayesianism, or what?

The philosophical consensus seems to be that there is no such thing as a single, well-identified scientific method, and that the sciences rely instead on an ever-evolving toolbox, which moreover is significantly different between, say, ahistorical (physics) and historical (evolutionary biology) sciences, or between the natural and social sciences.

Here too, however, the same problem that I mentioned above recurs: contra Haack, proponents of scientism do not seem to claim that there is a special scientific method, but on the contrary, that science is essentially co-extensive with reason itself. Once again, this isn’t a philosophically new position:

If we take in our hand any volume; of divinity or school metaphysics, for instance; let us ask, Does it contain any abstract reasoning concerning quantity or number? No. Does it contain any experimental reasoning concerning matter of fact and existence? No. Commit it then to the flames: for it can contain nothing but sophistry and illusion — David Hume (An Enquiry Concerning Human Understanding).

Both Ayer’s verifiability criterion and Hume’s fork suffer from serious philosophical problems, of course, but to uncritically deployed them as a blunt instrument against in defense of scientism is simply a result of willful and abysmal illiteracy.

Next to last, comes an attitude that seeks to deploy science to answer questions beyond its scope. It seems to me that it is exceedingly easy to come up with questions that either science is wholly unequipped to answer, or for which it can at best provide a (welcome!) degree of relevant background knowledge. I will leave it to colleagues in other disciplines to arrive at their own list, but as far as philosophy is concerned, the following list is just a start:

In metaphysics: what is a cause?

In logic: is modus ponens a type of valid inference?

In epistemology: is knowledge “justified true belief”?

In ethics: is abortion permissible once the fetus begins to feel pain?

In aesthetics: is there a meaningful difference between Mill’s “low” and “high”

pleasures?

pleasures? In philosophy of science: what role does genetic drift play in the logical structure of

evolutionary theory?

evolutionary theory? In philosophy of mathematics: what is the ontological status of mathematical objects, such as numbers?

The scientific literature on all the above is basically non-existent, while the philosophical one is huge. None of the above questions admits of answers arising from systematic observations or experiments. While empirical notions may be relevant to some of them (e.g., the one on abortion), it is philosophical arguments that provide the suitable approach.

Lastly, a sixth sign of scientism is the denial or denigration of the usefulness of nonscientific activities, particularly within the humanities. Saying that philosophy is “useless” because it doesn’t contribute to solving scientific problems (deGrasse Tyson, Hawking, Krauss, Nye), betrays a fundamental misunderstanding (and let’s be frank, simple ignorance) of what philosophy is. Ironically, the scientistic take could be turned on its head: on what empirical grounds, for instance, can we arrive at the value judgment that cosmology is “more important” than literature? Is the only thing that matters the discovery of facts about the natural world? Why? And while we are at it, why exactly do we take for granted that money spent on a new particle accelerator shouldn’t be spent on, say, cancer research? I’m not advocating such a position, I am simply pointing out that there is no scientific evidence that could settle the matter, and that scientistically-inclined writers tend, as Daniel Dennett famously said in Darwin’s Dangerous Idea, to take on board a lot of completely unexamined philosophical baggage.

In the end, it all comes down to what we mean by “science.” Perhaps we can reasonably agree that this is a classic example of a Wittgensteinian “family resemblance” concept, i.e., something that does not have precise boundaries, nor is it amenable to a precise definition in terms of necessary and jointly sufficient conditions. But as a scientist and a philosopher of science, I tend to see “science” as an evolving beast, historically and culturally situated, similar to the in-depth analysis provided by Helen Longino in her book, Science as Social Knowledge.

Science is a particular ensemble of epistemic and social practices — including a more or less faulty system of peer review, granting agencies, academic publications, hiring practices, and so on. This is different from “science” as it was done by Aristotle, or even by Galileo. There is a continuity, of course, between its modern incarnation and its historical predecessors, as well as between it and other fields (mathematics, logic, philosophy, history, and so forth).

But when scientistic thinkers pretend that any human activity that has to do with reasoning about facts is “science” they are attempting a bold move of naked cultural colonization, defining everything else either out of existence or into irrelevance. When I get up in the morning and go to work at City College in New York I take a bus and a subway. I do so on the basis of my empirical knowledge of the Metropolitan Transportation Authority system, which results — you could say — from years of “observations” and “experiments,” aimed at testing “hypotheses” about the system and its functionality. If you want to call that science, fine, but you end up sounding pretty ridiculous. And you are doing no favor to real science either.

Massimo Pigliucci is the K.D. Irani Professor of Philosophy at the City College of New York. His interests are in the philosophy of biology, the structure of evolutionary theory, and the nature of pseudoscience. His latest book, co-edited with Maarten Boudry, is Science Unlimited? The Challenges of Scientism (Chicago Press). He blogs at platofootnote.org.