Somebody once asked Niels Bohr why he had a horseshoe hanging above the front door of his house. Surely you, a world famous physicist, can't really believe that hanging a horseshoe above your door brings you luck? Of course not, Bohr replied, but I have been reliably informed that it will bring me luck whether I believe in it or not.

I profoundly admire Aldous Huxley, both for his philosophy and uncompromising sincerity. But I disagree with his advocacy of 'the chemical opening of doors into the Other World', and with his belief that drugs can procure 'what Catholic theologians call a gratuitous grace'. Chemically induced hallucinations, delusions and raptures may be frightening or wonderfully gratifying; in either case they are in the nature of confidence tricks played on one's own nervous system.

Creativity is a type of learning process where the teacher and pupil are located in the same individual.

In creating the human brain, evolution has wildly overshot the mark.

The inner censor of the mind of the true believer completes the work of the public censor; his self-discipline is as tyrannical as the obedience imposed by the regime; he terrorizes his own conscience into submission;he carries his private Iron Curtain inside his skull, to protect his illusions against the intrusion of reality.

Space-ships and time machines are no escape from the human condition. Let Othello subject Desdemona to a lie-detector test; his jealousy will still blind him to the evidence. Let Oedipus triumph over gravity; he won't triumph over his fate.

Adolescence is a kind of emotional seasickness. Both are funny, but only in retrospect.