Jonathan Haidt in This View of Life:
Reason has long been worshipped by philosophers and intellectuals. In Plato’s dialogue Timaeus, the gods created humankind with a soul of perfect rationality and inserted it into our spherical heads, which were “the most divine part of us and the lord of all that is in us.” (The Gods then realized that they had to create necks, to keep reason insulated from the seething passions of the rest of the body.) During the “age of reason,” the French revolutionaries pulled the Christs and crucifixes out of the cathedrals and replaced them with images of reason. And in our own time, the New Atheists have written books and started foundations urging people to fight religion with reason.
The New Atheist Sam Harris has even gone so far as to argue, in his book The Moral Landscape, that reason and science can tell us what is right and wrong. Morality is—in his definition—limited to questions about “the well-being of conscious creatures.” Well-being can be measured objectively, he says, by methods such as fMRI scans. Therefore, whatever practices, customs, and ways of living maximize those measurements are morally correct; others are morally wrong. He does not say that there is a single best society (hence the image of a landscape, with multiple peaks). But he claims that moral values are facts, no different from the kinds of facts discovered by chemists. Scientific methods give correct answer to questions in chemistry, and they can therefore do so for morality as well. Harris’s confidence in his reasoned argument is so strong that he has issued The Moral Landscape Challenge: He will personally pay $10,000 to anyone who submits an essay so logically compelling that it makes him change his mind and renounce his views.