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?

In the opera we call love, the libretto is almost nothing.

The world is the expanding Greece and Greece is the shrinking world.

A stand can be made against invasion by an army; no stand can be made against invasion by an idea.

Thought is the labor of the intellect, reverie is its pleasure.

To breathe Paris is to preserve one's soul.

Proverty and wealth are comparative sins.