The movement’s rhetoric suggests that if governments simply fund and heed scientific research, the world will march steadily toward peace and prosperity. Applying science to politics will create “an unbroken chain of inquiry, knowledge, and public benefit for all.” This is, dare I say, an unscientific conception of human action. A huge body of social-scientific literature—or just a good, hard look at the political scene—shows that conflict, uncertainty, and collective self-interest would remain central features of democratic politics even if all of the disputants took scientific findings as their starting point for policy recommendations.

In a 2004 essay, Daniel Sarewitz, a professor at Arizona State University, challenged the longstanding expectation that bringing science to bear on political questions will reduce or eliminate disputation. In fact, he noted that “scientized” political issues—most notably, the climate debate—generate particularly sharp controversies precisely because the participants can focus exclusively on questions of scientific validity while obscuring the values and interests that shape their positions. Coal producers seeking to throw off environmental regulations, for example, will tend to highlight uncertainties in the scientific understanding of carbon dioxide’s atmospheric effects, rather than making an explicit case for choosing policies that benefit their industry over policies aimed at climate remediation.

Taking Sarewitz seriously suggests that values, interests, and interpretive frames should be at the center of policy formation. Here, the march organizers offer little help. As they portray the world, there are only two kinds of people: pro-science and anti-science. Likewise, there are only two ways of acting: on the basis of science—facts, truth, data, evidence—or unscientifically, in accordance with ideology, self-interest, or mere caprice. “Political decision-making that impacts the lives of Americans and the world at large,” the march website declares, “should make use of peer-reviewed evidence and scientific consensus, not personal whims and decrees.”

Proceeding without any consideration of science’s latest findings is certainly dangerous. Yet the march organizers simplify the relation of science to action—political or otherwise—to the point where their prescriptions may become counterproductive. One source of today’s skepticism toward science as a political resource is the failure of mid-20th-century governments to deliver on the extravagant promises associated with the application of science to society. It is easy enough to laugh at postwar science boosters, with their utopian visions of virtually costless nuclear energy, flying cars, and moon colonies—not to mention a quick and painless end to poverty. But the failure of those visions to materialize had very real effects. It would be ironic indeed if the current push for science-based policy were to bear fruit and replicate the overdrawn expectations—and the resulting disappointments—of the 1950s and 1960s.