The study of geometry is a petty and idle exercise of the mind, if it is applied to no larger system than the starry one. Mathematics should be mixed not only with physics but with ethics; that is mixed mathematics.

It enhances our sense of the grand security and serenity of nature to observe the still undisturbed economy and content of the fishes of this century, their happiness a regular fruit of the summer.

Let every one mind his own business, and endeavor to be what he was made.

You know about a person who deeply interests you more than you can be told. A look, a gesture, an act, which to everybody else is insignificant tells you more about that one than words can.

If you're familiar with a principle you don't have to be familiar with all of its applications.

I rejoice that horses and steers have to be broken before they can be made the slaves of men, and that men themselves have some wild oats still left to sow before they become submissive members of society. Undoubtedly, all men are not equally fit subjects for civilization; and because the majority, like dogs and sheep, are tame by inherited disposition, this is no reason why the others should have their natures broken that they may be reduced to the same level.

Simplicity is the law of Nature for man as well as for flowers. When the tapestry (corolla) of the nuptial bed (calyx) is excessive, luxuriant, it is unproductive. The fertile flowers are single, not double.