“It appears now to be universally admitted that, before the exile, the Israelites had no belief in rewards and punishments after death, nor in anything similar to the Christian heaven and hell; but our story proves that it would be an error to suppose that they did not believe in the continuance of individual existence after death by a ghostly simulacrum of life. Nay, I think it would be very hard to produce conclusive evidence that they disbelieved in immortality; for I am not aware that there is anything to show that they thought the existence of the souls of the dead in Sheol ever came to an end. But they do not seem to have conceived that the condition of the souls in Sheol was in any way affected by their conduct in life. If there was immortality, there was no state of retribution in their theology. Samuel expects Saul and his sons to come to him in Sheol.”

“History warns us ... that it is the customary fate of new truths to begin as heresies and to end as superstitions.”

“The man of science has learned to believe in justification, not by faith, but by verification.”

“Perhaps the most valuable result of all education is the ability to make yourself do the thing you have to do, when it ought to be done, whether you like it or not. It is the first lesson that ought to be learned and however early a man's training begins, it is probably the last lesson that he learns thoroughly.”

“The scientific spirit is of more value than its products, and irrationally held truths may be more harmful than reasoned errors.”

“I am too much of a skeptic to deny the possibility of anything.”

“The most considerable difference I note among men is not in their readiness to fall into error but in their readiness to acknowledge these inevitable lapses.”

“The great end of life is not knowledge but action.”

“Act decidedly and take the consequences. No good is ever done by hesitation.”

“The most considerable difference I note among men is not in their readiness to fall into error but in their readiness to acknowledge these inevitable lapses.”

“Of moral purpose I see no trace in Nature. That is an article of exclusively human manufacture and very much to our credit.”