Steven Pinker has an interesting and revealing essay in The New Republic dismissing the charges of “scientism” that are often leveled by the philosophically, artistically and religiously-minded against certain authors, polemicists and science popularizers. “The term,” he writes, “is anything but clear, more of a boo-word than a label for any coherent doctrine,” which inspires him to try to reappropriate “scientism” as a positive descriptor — denoting, he suggests, a belief in the intelligibility of the world and a commitment to the difficult-but-necessary quest for real objectivity about its workings, both of which which should inform our understanding of non-scientific spheres as well.

If this is scientism then obviously no sensible person should have a problem with it. But the “boo-word” version of the phenomenon — the scientism that makes entirely unwarranted claims about what the scientific method can tell us, wraps “is” in the mantle of “ought” and vice versa, and reduces culture to biology at every opportunity — is much easier to pin down than Pinker suggests. Indeed, he helpfully supplies a perfect example of in his own essay, in his discussion of what modern science has allegedly meant for our understanding of personal and political morality:

… the findings of science entail that the belief systems of all the world’s traditional religions and cultures—their theories of the origins of life, humans, and societies—are factually mistaken. We know, but our ancestors did not, that humans belong to a single species of African primate that developed agriculture, government, and writing late in its history. We know that our species is a tiny twig of a genealogical tree … We know that we live on a planet that revolves around one of a hundred billion stars in our galaxy, which is one of a hundred billion galaxies in a 13.8-billion-year-old universe, possibly one of a vast number of universes. We know that our intuitions about space, time, matter, and causation are incommensurable with the nature of reality on scales that are very large and very small. We know that the laws governing the physical world (including accidents, disease, and other misfortunes) have no goals that pertain to human well-being. There is no such thing as fate, providence, karma, spells, curses, augury, divine retribution, or answered prayers—though the discrepancy between the laws of probability and the workings of cognition may explain why people believe there are. And we know that we did not always know these things, that the beloved convictions of every time and culture may be decisively falsified, doubtless including some we hold today.

So here we have a defensible-if-tendentious account of how the progress of science has undercut the world-pictures bequeathed to us by tradition, intuition and religion. Now an innocent reader might assume that the crack-up of these world pictures, with their tight link between cosmic design and human purposes, might make moral consensus more difficult to realistically achieve. After all, if our universe’s testable laws and empirical realities have no experimentally-verifiable connection to human ends and values, then one would expect rival ideas of the good to have difficulty engaging with one another fruitfully, escaping from the pull of relativism or nihilism, and/or grounding their appeals in anything stronger than aesthetic preference.

But obviously that isn’t where Pinker is going:

In other words, the worldview that guides the moral and spiritual values of an educated person today is the worldview given to us by science. Though the scientific facts do not by themselves dictate values, they certainly hem in the possibilities. By stripping ecclesiastical authority of its credibility on factual matters, they cast doubt on its claims to certitude in matters of morality. The scientific refutation of the theory of vengeful gods and occult forces undermines practices such as human sacrifice, witch hunts, faith healing, trial by ordeal, and the persecution of heretics. The facts of science, by exposing the absence of purpose in the laws governing the universe, force us to take responsibility for the welfare of ourselves, our species, and our planet. For the same reason, they undercut any moral or political system based on mystical forces, quests, destinies, dialectics, struggles, or messianic ages. And in combination with a few unexceptionable convictions— that all of us value our own welfare and that we are social beings who impinge on each other and can negotiate codes of conduct—the scientific facts militate toward a defensible morality, namely adhering to principles that maximize the flourishing of humans and other sentient beings. This humanism, which is inextricable from a scientific understanding of the world, is becoming the de facto morality of modern democracies, international organizations, and liberalizing religions, and its unfulfilled promises define the moral imperatives we face today.

This is an impressively swift march from allowing, grudgingly, that scientific discoveries do not “dictate” values to asserting that they “militate” very strongly in favor of … why, of Steven Pinker’s very own moral worldview! You see, because we do not try witches, we must be utilitarians! Because we know the universe has no purpose, we must imbue it with the purposes of a (non-species-ist) liberal cosmopolitanism! Because of science, we know that modern civilization has no dialectic or destiny … so we must pursue its “unfulfilled promises” and accept its “moral imperatives” instead!

Since Pinker’s last book was an extended rehabilitation of the Whig interpretation of history, it’s not surprising to see him make this kind of case. But it’s intellectually parochial and logically slipshod, and it’s also depends on a kind of present-ist chauvinism: His argument seems vaguely plausible only if you regard the paradigmatic shaped-by-science era as the post-Cold War Pax Americana rather than, say, the chaos of 1914-45, when instead of a humanist consensus the scientifically-advanced West featured radically-incommensurate moral worldviews basically settling their differences by force of arms.

Like Sam Harris, who wrote an entire book claiming that “science” somehow vindicates his preferred form of philosophical utilitarianism (when what he really meant was that if you assume utilitarian goals, science can help you pursue them), Pinker seems to have trouble imagining any reasoning person disagreeing about either the moral necessity of “maximizing human flourishing” or the content of what “flourishing” actually means — even though recent history furnishes plenty of examples and a decent imagination can furnish many more. Like his whiggish antecedents, he mistakes a real-but-complicated historical relationship between science and humanism for a necessary intellectual line in which the latter vindicates the former, or at least militates strongly in its favor. And his invocation of “the scientific facts” to justify what is, at bottom, a philosophical preference for Mill over Nietzsche is the pretty much the essence of what critics mean by scientism: Empirically overconfident, intellectually unsubtle, and deeply incurious about the ways in which human beings can rationally disagree.