Believe it or not—and I suspect most readers will not—there's a liberal war on science. Say what?

We are well aware of the Republican war on science from the eponymous 2006 book (Basic Books) by Chris Mooney, and I have castigated conservatives myself in my 2006 book Why Darwin Matters (Henry Holt) for their erroneous belief that the theory of evolution leads to a breakdown of morality. A 2012 Gallup poll found that “58 percent of Republicans believe that God created humans in their present form within the last 10,000 years,” compared with 41 percent of Democrats. A 2011 survey by the Public Religion Research Institute found that 81 percent of Democrats but only 49 percent of Republicans believe that Earth is getting warmer. Many conservatives seem to grant early-stage embryos a moral standing that is higher than that of adults suffering from debilitating diseases potentially curable through stem cells. And most recently, Missouri Republican senatorial candidate Todd Akin gaffed on the ability of women's bodies to avoid pregnancy in the event of a “legitimate rape.” It gets worse.

The left's war on science begins with the stats cited above: 41 percent of Democrats are young Earth creationists, and 19 percent doubt that Earth is getting warmer. These numbers do not exactly bolster the common belief that liberals are the people of the science book. In addition, consider “cognitive creationists”—whom I define as those who accept the theory of evolution for the human body but not the brain. As Harvard University psychologist Steven Pinker documents in his 2002 book The Blank Slate (Viking), belief in the mind as a tabula rasa shaped almost entirely by culture has been mostly the mantra of liberal intellectuals, who in the 1980s and 1990s led an all-out assault against evolutionary psychology via such Orwellian-named far-left groups as Science for the People, for proffering the now uncontroversial idea that human thought and behavior are at least partially the result of our evolutionary past.

There is more, and recent, antiscience fare from far-left progressives, documented in the 2012 book Science Left Behind (PublicAffairs) by science journalists Alex B. Berezow and Hank Campbell, who note that “if it is true that conservatives have declared a war on science, then progressives have declared Armageddon.” On energy issues, for example, the authors contend that progressive liberals tend to be antinuclear because of the waste-disposal problem, anti–fossil fuels because of global warming, antihydroelectric because dams disrupt river ecosystems, and anti–wind power because of avian fatalities. The underlying current is “everything natural is good” and “everything unnatural is bad.”

Whereas conservatives obsess over the purity and sanctity of sex, the left's sacred values seem fixated on the environment, leading to an almost religious fervor over the purity and sanctity of air, water and especially food. Try having a conversation with a liberal progressive about GMOs—genetically modified organisms—in which the words “Monsanto” and “profit” are not dropped like syllogistic bombs. Comedian Bill Maher, for example, on his HBO Real Time show on October 19, 2012, asked Stonyfield Farm CEO Gary Hirshberg if he would rate Monsanto as a 10 (“evil”) or an 11 (“f—ing evil”)? The fact is that we've been genetically modifying organisms for 10,000 years through breeding and selection. It's the only way to feed billions of people.

Surveys show that moderate liberals and conservatives embrace science roughly equally (varying across domains), which is why scientists like E. O. Wilson and organizations like the National Center for Science Education are reaching out to moderates in both parties to rein in the extremists on evolution and climate change. Pace Barry Goldwater, extremism in the defense of liberty may not be a vice, but it is in defense of science, where facts matter more than faith—whether it comes in a religious or secular form—and where moderation in the pursuit of truth is a virtue.