Life consists of what man is thinking about all day.

Life is full of troubles and vexations, that one must either rise above it by means of corrected thoughts, or leave it.

Man talks about everything, and he talks about everything as though the understanding of everything were all inside him.

There is nothing alive more agonized than man / of all that breathe and crawl across the earth.

Every man has a long list of things that should be done, but which he knows can't be done. Yet he continues to talk about them as long as he lives.

A man is what he thinks about all day long

Conversation is an art in which a man has all mankind for his competitors, for it is that which all are practising every day while they live.

The man who is forever disturbed about the problems of humanity either has no problems of his own or has refused to face them.

The trickiest thing is the nature of man, apparent in everything.

Man is, so to speak, an endless and infinitely varied repetition: and if we know what one man feels, we so far know what a thousand feel in the sanctuary of their being. Our feeling of general humanity is at once an aggregate of a thousand different truths, and it is also the same truth a thousand times told.

Man is so wretched that, while he shapes all of his conduct to gratify his passions, he groans incessantly under their tyranny. He can endure neither their violence, nor the violence that he would have to inflict on himself in order to rid himself of their yoke. He is frustrated not only by his vices, but also by the things that would cure them; and he cannot come to terms either with the discomfort of his afflictions or with the task of curing himself.

The average man takes life as a trouble. He is in a chronic state of irritation at the whole performance. He does not learn to differentiate between troubles and difficulties, usually, until some real trouble bowls him over. He fusses about pin-pricks until a mule kicks him. Then he learns the difference.

The major and almost only theme of all my work is the struggle of man with "God": the unyielding, inextinguishable struggle of the naked worm called "man" against the terrifying power and darkness of the forces within him and around him.

Great problems are now being handled, keeping every thinking man in suspense; the unity or multiplicity of human races; the creation of man 1,000 years or 1,000 centuries ago; the fixity of species, or the slow and progressive transformation of one species into another; the eternity of matter; the idea of a God unnecessary: such are some of the questions that humanity discusses nowadays.