The known is finite, the unknown infinite; intellectually we stand on an islet in the midst of an illimitable ocean of inexplicability. Our business in every generation is to reclaim a little more land, to add something to the extent and the solidity of our possessions.

Science has fulfilled her function when she has ascertained and enunciated truth.

The dogma of the infallibility of the Bible is no more self-evident than is that of the infallibility of the popes.

That man, I think, has had a liberal education, who has been so trained in youth that his body is the ready servant of his will.

It is wrong for a man to say that he is certain of the objective truth of any proposition unless he can produce evidence which logically justifies that certainty. This is what Agnosticism asserts; and, in my opinion, it is all that is essential to Agnosticism. That which Agnostics deny and repudiate, as immoral, is the contrary doctrine, that there are propositions which men ought to believe without logically satisfactory evidence; and that reprobation ought to attach to the profession of disbelief in such inadequately supported propositions.

To quarrel with the uncertainty that besets us in intellectual affairs would be about as reasonable as to object to live one's life with due thought for the morrow because no man can be sure he will alive an hour hence.

The doctrine of transmigration… was a means of constructing a plausible vindication of the ways of the cosmos to man; … none but very hasty thinkers will reject it on the grounds of inherent absurdity.