The word “faith” is one of those magical words that can mean everything or nothing simultaneously. It’s used by those who accept its validity to mean a number of things that are entirely different, amounting to little more than a rhetorical trick used to shield their beliefs from scrutiny. Jerry Coyne agrees:
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…
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 (think Nicene and Athanasian Creeds), 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!