A bird is an instrument working according to mathematical law, which instrument it is within the capacity of man to reproduce with all its movements, but not with a corresponding degree of strength, though it is deficient only in the power of maintaining equilibrium. We may therefore say that such an instrument constructed by man is lacking in nothing except the life of the bird, and this life must needs be supplied from that of man.

Love shows itself more in adversity than in prosperity; as light does, which shines most where the place is darkest.

Those who are inspired by a model other than Nature, labor in vain.

Every action needs to be prompted by a motive. To know and to will are two operations of the human mind. Discerning, judging, deliberating are acts of the human mind.

...The world wouldn't be the world, without trouble.

Anyone who invokes authors in discussion is not using his intelligence but his memory.

People of higher talent work, even if they seem to do nothing