A common tactic of those who claim that science and religion are compatible is to argue that science, like religion, rests on faith: faith in the accuracy of what we observe, in the laws of nature or in the value of reason.
Daniel Sarewitz, director of a science policy center at Arizona State University, wrote this about the Higgs boson in the pages of Nature, one of the world's most prestigious science journals: "For those who cannot follow the mathematics, belief in the Higgs is an act of faith, not of rationality."
Such statements imply that science and religion are not that different because both seek the truth and use faith to find it. Indeed, science is often described as a kind of religion.
But that's wrong, for the "faith" we have in science is completely different from the faith believers have in God and the dogmas of their creed. To see this, consider the following four statements:
"I have faith that, because I accept Jesus as my personal savior, I will join my friends and family in Heaven."
"My faith tells me that the Messiah has not yet come, but will someday."
"I have strep throat, but I have faith that this penicillin will clear it up."
"I have faith that when I martyr myself for Allah, I will receive 72 virgins in Paradise."
All of these use the word faith, but one uses it differently. The three religious claims (Christian, Jewish and Muslim, respectively) represent faith as defined by philosopher Walter Kaufmann: "intense, usually confident, belief that is not based on evidence sufficient to command assent from every reasonable person."
Indeed, there is no evidence beyond revelation, authority and scripture to support the religious claims above, and most of the world's believers would reject at least one of them. To state it bluntly, such faith involves pretending to know things you don't. Behind it is wish-thinking, as clearly expressed in Hebrews 11:1: "Now faith is the substance of things hoped for, the evidence of things not seen."
In contrast, the third statement relies on evidence: Penicillin almost invariably kills streptococcus bacteria. In such cases the word faith doesn't mean "belief without good evidence," but "confidence derived from scientific tests and repeated, documented experience."
You have faith (that is, confidence) that the sun will rise tomorrow because it always has, and there's no evidence that the Earth has stopped rotating or the sun has burnt out. You have faith in your doctor because, presumably, she has treated you and others successfully, and you know that what she prescribes is tested scientifically. You wouldn't go to a shaman or a spiritual healer for strep throat — unless you want to waste your money.
The conflation of faith as "unevidenced belief" with faith as "justified confidence" is simply a word trick used to buttress religion. In fact, you'll never hear a scientist saying, "I have faith in evolution" or "I have faith in electrons." Not only is such language alien to us, but we know full well how those words can be misused in the name of religion.
What about the public and other scientists' respect for authority? Isn't that a kind of faith? Not really. When Richard Dawkins talks or writes about evolution, or Lisa Randall about physics, scientists in other fields — and the public — have confidence that they're right. But that, too, is based on the doubt and criticism inherent in science (but not religion): the understanding that their expertise has been continuously vetted by other biologists or physicists. In contrast, a priest's claims about God are no more demonstrable than anyone else's. We know no more now about the divine than we did 1,000 years ago.
The constant scrutiny of our peers ensures that science is largely self-correcting, so that we really can approach the truth about our universe. When Sarewitz claimed that "belief" in the Higgs boson was an act of faith rather than rationality, and when he compared it to Hindu belief in a sea of milk that sustains their gods, he was simply wrong. There is strong evidence for the Higgs boson, whose existence was confirmed last year by two independent teams using a giant accelerator and rigorous statistical analysis. But there isn't, and never will be, any evidence for that sea of milk.
Scientists give no special credence or authority to books, either, except insofar as they present comprehensive theories, novel analysis, or verified truths. When I became an evolutionary biologist, I was not required to swear to the truth of Darwin with my hand on the Origin of Species. Indeed, that book was wrong on many counts, including its fallacious theory of genetics. In contrast, many believers must regularly swear adherence to unchanging and dubious religious claims, and many ministers swear to uphold church doctrine.
So scientists don't have a quasi-religious faith in authorities, books or propositions without empirical support. Do we have faith in anything?
Two objects of scientific faith are said to be physical laws and reason. Doing science, it is said, requires unevidenced faith in the "orderliness of nature" and an "unexplained set of physical laws," as well as in the value of reason in determining truth.
Both claims are wrong.
The orderliness of nature — the set of so-called natural laws — is not an assumption but an observation. It is logically possible that the speed of light could vary from place to place, and while we'd have to adjust our theories to account for that, or dispense with certain theories altogether, it wouldn't be a disaster.
Other natural laws, such as the relative masses of neutrons and protons, probably can't be violated in our universe. We wouldn't be here to observe them if they were — our bodies depend on regularities of chemistry and physics. We take nature as we find it, and sometimes it behaves predictably.
What about faith in reason? Wrong again. Reason — the habit of being critical, logical and of learning from experience — is not an a priori assumption but a tool that's been shown to work. It's what produced antibiotics, computers and our ability to sequence DNA. We don't have faith in reason; we use reason because, unlike revelation, it produces results and understanding. Even discussing why we should use reason employs reason.
Finally, isn't science at least based on the faith that it's good to know the truth? Hardly. The notion that knowledge is better than ignorance is not a quasi-religious faith, but a preference: We prefer to know what's right because what's wrong usually doesn't work.
We don't describe plumbing or auto mechanics as resting on the faith that it's better to have your pipes and cars in working order, yet people in these professions also depend on finding truth.
One can dispel the "science as faith" canard in a single paragraph, and I'll let Richard Dawkins have the honor:
There is a very, very important difference between feeling strongly, even passionately, about something because we have thought about and examined the evidence for it on the one hand, and feeling strongly about something because it has been internally revealed to us, or internally revealed to somebody else in history and subsequently hallowed by tradition. There's all the difference in the world between a belief that one is prepared to defend by quoting evidence and logic and a belief that is supported by nothing more than tradition, authority or revelation.
So the next time you hear someone described as a "person of faith," remember that although it's meant as praise, it's really an insult.
Jerry A. Coyne is a professor of ecology and evolution at the University of Chicago and author of "Why Evolution Is True." His website is www.whyevolutionistrue.com.
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