Change your opinions, keep to your principles; change your leaves, keep intact your roots.

One cannot resist an idea whose time has come.

I believe that pity is a law like justice, and that kindness is a duty like uprightness. That which is weak has a right to the kindness and pity of that which is strong. In the relations of man with the animals...there is a great ethic, scarcely perceived as yet, which will at length break through into the light, and which will be the corollary and the complement to humans ethics. Are there not here unsounded depths for the thinker? Is one to think oneself mad because one has the sentiment of universal pity in one's heart?

To know, to think, to dream. That is everything.

Go out in the world and work like money doesn't matter, sing as if no one is listening, love as if you have never been hurt, and dance as if no one is watching.

Every bird which flies has the thread of the infinite in its claw.

. . .where there is no more hope, song remains.