What is commonly called friendship is only a little more honor among rogues.

In the meanest are all the materials of manhood, only they are not rightly disposed.

For my part, I could easily do without the post-office. I think that there are very few important communications made through it.

Man's moral nature is a riddle which only eternity can solve.

It is remarkable that, notwithstanding the universal favor with which the New Testament is outwardly received, and even the bigotry with which it is defended, there is no hospitality shown to, there is no appreciation of, the order of truth with which it deals. I know of no book that has so few readers. There is none so truly strange, and heretical, and unpopular. To Christians, no less than Greeks and Jews, it is foolishness and a stumbling-block.

We can never have enough of Nature.

It is never too late to give up our prejudices. No way of thinking or doing, however, ancient, can be trusted without proof. ... Old deeds for old people, and new deeds for new.