The principles of logic and mathematics are true simply because we never allow them to be anything else. And the reason for this is that we cannot abandon them without contradicting ourselves, without sinning against the rules which govern the use of language, and so making our utterances self-stultifying. In other words, the truths of logic and mathematics are analytic propositions or tautologies.

The misfortunes which God is represented in the book of Job as allowing Satan to inflict on Job, merely to test his faith, are indications, if not of positive malevolence, at least of a suspicious and ruthless insecurity, which is characteristic more of a tyrant than of a wholly powerful and benevolent deity.

A prevalent fallacy is the assumption that a proof of an afterlife would also be a proof of the existence of a deity. This is far from being the case. If, as I hold, there is no good reason to believe that a god either created or presides over this world, there is equally no good reason to believe that a god created or presides over the next world, on the unlikely supposition that such a thing exists.

Why should you mind being wrong if someone can show you that you are?

It is time, therefore, to abandon the superstition that natural science cannot be regarded as logically respectable until philosophers have solved the problem of induction. The problem of induction is, roughly speaking, the problem of finding a way to prove that certain empirical generalizations which are derived from past experience will hold good also in the future.

No moral system can rest solely on authority.

It is possible to be a meta-physician without believing in a transcendent reality; for we shall see that many metaphysical utterances are due to the commission of logical errors, rather than to a conscious desire on the part of their authors to go beyond the limits of experience.