In health there is freedom. Health is the first of all liberties.

A woman is sometimes fugitive, irrational, indeterminable, illogical and contradictory. A great deal of forbearance ought to be shown her, and a good deal of prudence exercised with regard to her, for she may bring about innumerable evils without knowing it. Capable of all kinds of devotion, and of all kinds of treason, monster incomprehensible, raised to the second power, she is at once the delight and the terror of man.

[T]he habit of scientific analysis ... exhausts the material offered to it.

Truth above all, even when it upsets us and overwhelms us.

Time is the supreme illusion. It is but the inner prism by which we decompose being and life, the mode under which we perceive successively what is simultaneous in idea.

To know how to suggest is the art of teaching.

A man must be able to cut a knot, for everything cannot be untied; he must know how to disengage what is essential from the detail in which it is enwrapped, for everything cannot be equally considered; in a word, he must be able to simplify his duties, his business and his life.