“Believing a given proposition is a matter of believing that it faithfully represents some state of the world, and this fact yields some immediate insights into the standards by which our beliefs should function. In particular, it reveals why we cannot help but value evidence and demand that propositions about the world logically cohere.”

“In adaptive terms, belief has been extraordinarily useful. It is, after all, by believing various propositions about the world that we predict events and consider the likely consequences of our actions. Beliefs are principles of action: whatever they may be at the level of the brain, they are processes by which our understanding (and misunderstanding) of the world is represented and made available to guide our behavior.”

“Argument is to me the air I breathe. Given any proposition, I cannot help believing the other side and defending it.”

“When considering the truth of a proposition, one is either engaged in an honest appraisal of the evidence and logical arguments, or one isn't. Religion is one area of our lives where people imagine that some other standard of intellectual integrity applies.”

“Moreover, the attitude that one ought to believe such and such a proposition, independently of the question whether there is evidence in its favor, is an attitude which produces hostility to evidence and causes us to close our minds to every fact that does not suit our prejudices.”

“We believe that it is possible for scientific work to gain some knowledge about the reality of the world, by means of which we can increase out power and in accordance with which we can arrange our life. If this belief is an illusion, then we are in the same position as you. But science has given us evidence by its numerous and important successes that it is no illusion.”