Aristotle discovered all the half-truths which were necessary to the creation of science.

A clash of doctrine is not a disaster, it is an opportunity.

The great achievements of the past were the adventures of the past. Only the adventurous can understand the greatness of the past.

Without deductive logic science would be entirely useless. It is merely a barren game to ascend from the particular to the general, unless afterwards we can reverse the process and descend from the general to the particular, ascending and descending like angels on Jacob's ladder.

Governments are best classified by considering who are the 'somebodies' they are in fact endeavouring to satisfy.

In the history of the world the prize has not gone to those species which specialized in methods of violence, or even in defensive armor. In fact, nature began with producing animals encased in hard shells for defense against the ill of life. But smaller animals, without external armor, warm-blooded, sensitive, alert, have cleared those monsters off the face of the earth.

Nature is probably quite indifferent to the aesthetic preferences of mathematicians.