If conquerors be regarded as the engine-drivers of History, then the conquerors of thought are perhaps the pointsmen who, less conspicuous to the traveler's eye, determine the direction of the journey.

As modern physics started with the Newtonian revolution, so modern philosophy starts with what one might call the Cartesian Catastrophe. The catastrophe consisted in the splitting up of the world into the realms of matter and mind, and the identification of 'mind' with conscious thinking. The result of this identification was the shallow rationalism of l' esprit Cartesien, and an impoverishment of psychology which it took three centuries to remedy even in part.

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.

One question that people always ask at home is never asked here: "What happened to Communism in Russia?" Everybody yawns when a visitor brings it up, because the answer is so obvious to every Russian. The answer is that there never was Communism in Russia; there were only communists.

Aggressiveness is not the main trouble with the human species, but rather an excess capacity for fanatical devotion.

Coincidence may be described as the chance encounter of two unrelated causal chains which - miraculously, it seems - merge into a significant event.

Newton's apple and Cezanne's apple are discoveries more closely related than they seem.