Certain characteristics of the subject are clear. To begin with, we do not in this subject deal with particular things or particular properties: we deal formally with what can be said about any thing or any property. We are prepared to say that one and one are two, but not that Socrates and Plato are two.

The human race may well become extinct before the end of the century. Speaking as a mathematician, I should say the odds are about three to one against survival.

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.

I feel life is so small unless it has windows into other worlds.

Unfortunately, however, power is sweet, and the man who in the beginning seeks power merely in order to have scope for his benevolence is likely, before long, to love the power for its own sake.

Fear is the parent of cruelty, and therefore it is no wonder if cruelty and religion have gone hand-in-hand. It is because fear is at the basis of those two things. In this world we can now begin a little to understand things, and a little to master them by the help of science, which has forced its way step by step against the Christian religion, against the churches, and against the opposition of all the old precepts.

To create a healthy philosophy you should renounce metaphysics but be a good mathematician.