40 Quotes by A.J. Ayer

We say that a sentence is factually significant to any given person, if, and only if, he knows how to verify the proposition which it purports to express.

Bertrand Russell would not have wished to be called a saint of any description; but he was a great and good man.

The only possible basis for a sound morality is mutual tolerance and respect: tolerance of one another’s customs and opinions; respect for one another’s rights and feelings; awareness of one another’s needs.

The fact that people have religious experiences is interesting from the psychological point of view, but it does not in any way imply that there is such a thing as religious knowledge...Unless he can formulate this 'knowledge' in propositions that are empirically verifiable, we may be sure that he is deceiving himself.

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.

It seems that I have spent my entire life trying to make life more rational and that it was all wasted effort.

I suddenly stopped and looked out at the sea and thought, my God, how beautiful this is ... for 26 years I had never really looked at it before.

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

In other words, the propositions of philosophy are not factual, but linguistic in character - that is, they do not describe the behaviour of physical, or even mental, objects; they express definitions, or the formal consequences of definitions. Accordingly we may say that philosophy is a department of logic. For we will see that the characteristic mark of a purely logical enquiry, is that it is concerned with the formal consequences of our definitions and not with questions of empirical fact.