He who has so little knowledge of human nature as to seek happiness by changing anything but his own disposition will waste his life in fruitless efforts.

He that can swim needs not despair to fly; to swim is to fly in a grosser fluid, and to fly is to swim in a subtler. We are only to proportion our power of resistance to the different density of matter through which we are to pass. You will be necessarily upborne by the air if you can renew any impulse upon it faster than the air can recede from the pressure.

Consultation and compliance can conduce little to the perfection of any literary performance; for whoever is so doubtful of his own abilities as to encourage the remarks of others, will find himself every day embarrassed with new difficulties, and will harass his mind, in vain, with the hopeless labour of uniting heterogeneous ideas, digesting independent hints, and collecting into one point the several rays of borrowed light, emitted often with contrary directions.

Dogs have not the power of comparing. A dog will take a small piece of meat as readily as a large, when both are before him.

Books have always a secret influence on the understanding; we cannot at pleasure obliterate ideas; he that reads books of science, thogh without any fixed desire of improvement, will grow more knowing.

Man is a transitory being, and his designs must partake of the imperfections of their author. To confer duration is not always in our power. We must snatch the present moment, and employ it well, without too much solicitude for the future, and content ourselves with reflecting that our part is performed. He that waits for an opportunity to do much at once, may breathe out his life in idle wishes, and regret, in the last hour, his useless intentions and barren zeal.

Hope is necessary in every condition.