Aestheticism and radicalism must lead us to jettison reason, and to replace it by a desperate hope for political miracles. This irrational attitude which springs from intoxication with dreams of a beautiful world is what I call Romanticism. It may seek its heavenly city in the past or in the future; it may preach 'back to nature' or 'forward to a world of love and beauty'; but its appeal is always to our emotions rather than to reason. Even with the best intentions of making heaven on earth it only succeeds in making it a hell - that hell which man alone prepares for his fellow-men.

Ignorance is not a simple lack of knowledge but an active aversion to knowledge, the refusal to know, issuing from cowardice, pride, or laziness of mind.

Almost everyone... seems to be quite sure that the differences between the methodologies of history and of the natural sciences are vast. For, we are assured, it is well known that in the natural sciences we start from observation and proceed by induction to theory. And is it not obvious that in history we proceed very differently? Yes, I agree that we proceed very differently. But we do so in the natural sciences as well.

Instead of encouraging the student to devote himself to his studies for the sake of studying, instead of encouraging in him a real love for his subject and for inquiry, he is encouraged to study for the sake of his personal career; he is led to acquire only such knowledge as is serviceable in getting him over the hurdles which he must clear for the sake of his advancement.

Rationalism is an attitude of readiness to listen to contrary arguments and to learn from experience... of admitting that "I may be wrong and you may be right and, by an effort, we may get nearer the truth."

The moral decisions of others should be treated with respect, as long as such decisions do not conflict with the principle of tolerance.

It is complete nihilism to propose laying down arms in a world where atom bombs are around. It is very simple: there is no way of achieving peace other than with weapons.