Señor, las tristezas no se hicieron para las bestias, sino para los hombres; pero si los hombres las sienten demasiado, se vuelven bestias...

He was reminded that men may be angels, but they are animals, too. They are driven by uncontrollable forces and only the love of other people makes it possible for them to survive. Men are lonely and are stricken in the night. They lock their jaws against themselves. They scream like animals, and even though they ridicule love and the forces of destruction, they are themselves theatres for the operation of such forces.

Do you not believe that animals know grief and fear and pain? The world of men is not an easy one for them.

Men are the devils of the earth, and the animals are the tormented souls.

- <i>On Religion</i>

When they face desperation... human beings become animals.

Men are the only animals that devote themselves, day in and day out, to making one another unhappy. It is an art like any other. Its virtuosi are called altruists.

Believe me, every man has his secret sorrows, which the world knows not; and oftimes we call a man cold when he is only sad.

It can truly be said: Men are the devils of the earth, and the animals are the tormented souls.

People thought up the idea that animals don't have the same capability of suffering as humans, because otherwise they couldn't bear the knowledge that they are surrounded by a world of nature that is horror, and nothing but horror.

He who is cruel to animals becomes hard also in his dealings with men. We can judge the heart of a man by his treatment of animals.

Truly great men must, I think, experience great sorrow on the earth.

What unhappy beings men are! They constantly waver between false hopes and silly fears, and instead of relying on reason they create monsters to frighten themselves with, and phantoms which lead them astray.

Men are reasoning rather than reasonable animals.

A notorious inability to express emotions makes human beings the only animals capable of suicide.