Every advance in civilization has been denounced as unnatural while it was recent

The Christian view that all intercourse outside marriage is immoral was, as we see in the above passages from St. Paul, based upon the view that all sexual intercourse, even within marriage, is regrettable. A view of this sort, which goes against biological facts, can only be regarded by sane people as a morbid aberration. The fact that it is embedded in Christian ethics has made Christianity throughout its whole history a force tending towards mental disorders and unwholesome views of life.

Mathematics takes us into the region of absolute necessity, to which not only the actual word, but every possible word, must conform.

I say quite deliberately that the Christian religion, as organized in its Churches, has been and still is the principal enemy of moral progress in the world.

While I am as convinced a Socialist as the most ardent Marxian, I do not regard Socialism as a gospel of proletarian revenge, nor even, primarily, as a means of securing economic justice. I regard it primarily as an adjustment to machine production demanded by considerations of common sense, and calculated to increase the happiness, not only of proletarians, but of all except a tiny minority of the human race.

A man who has once perceived, however temporarily and however briefly, what makes greatness of soul, can no longer be happy if he allows himself to be petty, self-seeking, troubled by trivial misfortunes, dreading what fate may have in store for him. The man capable of greatness of soul will open wide the windows of his mind, letting the winds blow freely upon it from every portion of the universe.

William James describes a man who got the experience from laughing-gas; whenever he was under its influence, he knew the secret of the universe, but when he came to, he had forgotten it. At last, with immense effort, he wrote down the secret before the vision had faded. When completely recovered, he rushed to see what he had written. It was 'A smell of petroleum prevails throughout'.