A day for toil, an hour for sport, but for a friend is life too short.

Nature magically suits a man to his fortunes, by making them the fruit of his character.

Let me admonish you, first of all, to go alone; to refuse the good models, even those which are sacred in the imagination of men, and dare to love God without mediator or veil.

Tobacco, coffee, alcohol, hashish, prussic acid, strychnine, are weak dilutions; the surest poison is time. This cup which nature puts to our lips, has a wonderful virtue, surpassing that of any other draught. It opens the senses, adds power, fills us with exalted dreams, which we call hope, love, ambition, science; especially it creates a craving for larger draughts of itself.

Genius detects through the fly, through the caterpillar, through the grub, through the egg, the constant individual; through countless individuals the fixed species; through many species the genus; through all genera the steadfast type; through all the kingdoms of organized life the eternal unity. Nature is a mutable cloud which is always and never the same.

Thought makes everything fit for use.

You must pay for conformity. All goes well as long as you run with conformists. But you, who are honest men in other particulars, know that there is alive somewhere a man whose honesty reaches to this point also, that he shall not kneel to false gods, and, on the day when you meet him, you sink into the class of counterfeits.