“Not all superstitions are dark and cruel. I once received a communication from the god Osiris. He was living at that time in a suburb of Boston.”

“As against solipsism it is to be said, in the first place, that it is psychologically impossible to believe, and is rejected in fact even by those who mean to accept it. I once received a letter from an eminent logician, Mrs. Christine Ladd-Franklin, saying that she was a solipsist, and was surprised that there were no others. Coming from a logician and a solipsist, her surprise surprised me.”

“In America everybody is of the opinion that he has no social superiors, since all men are equal, but he does not admit that he has no social inferiors, for, from the time of Jefferson onward, the doctrine that all men are equal applies only upwards, not downwards.”

“Morality in sexual relations, when it is free from superstition, consists essentially in respect for the other person, and unwillingness to use that person solely as a means of personal gratification, without regard to his or her desires.”

“Fear is the main source of superstition, and one of the main sources of cruelty. To conquer fear is the beginning of wisdom.”

“You all know the argument from design: everything in the world is made just so that we can manage to live in the world, and if the world was ever so little different, we could not manage to live in it. That is the argument from design. It sometimes takes a rather curious form; for instance, it is argued that rabbits have white tails in order to be easy to shoot. I do not know how rabbits would view that application.”

“Collective wisdom, alas, is no adequate substitute for the intelligence of individuals. Individuals who opposed received opinions have been the source of all progress, both moral and intellectual. They have been unpopular, as was natural.”