All instincts that do not discharge themselves outwardly turn inward - this is what I call the internalization of man: thus it was that man first developed what was later called his soul.

Tell me, my brother, what do we think bad, and worst of all? Is it not DEGENERATION?-And we always suspect degeneration when the bestowing soul is lacking.

Envy and jealousy are the private parts of the human soul. Perhaps the comparison can be extended.

At the risk of displeasing innocent ears I submit that egoism belongs to the essence of a noble soul.

Just as bones, tissues, intestines, and blood vessels are enclosed in a skin that makes it possible to bear the sight of a human being, so the agitations and passions of the soul are wrapped up in vanity: it is the soul's skin.

A degree of culture, and assuredly a very high one, is attained when man rises above superstitions and religious notions and fears, and, for instance, no longer believes in guardian angels or in original sin, and has also ceased to talk of the salvation of his soul.