Man is the product of causes which had no prevision of the end they were achieving; his origin, his growth, his hopes and fears, his loves and beliefs, are but the outcome of accidental collocations of atoms; no fire, no heroism, no intensity of though and feeling, can preserve an individual life beyond the grave.

So far I have been speaking of theoretical science, which is an attempt to understand the world. Practical science, which is an attempt to change the world, has been important from the first, and has continually increased in importance, until it has almost ousted theoretical science from men's thoughts.

There is no need to worry about mere size. We do not necessarily respect a fat man more than a thin man. Sir Isaac Newton was very much smaller than a hippopotamus, but we do not on that account value him less.

More and more people are becoming unable to accept traditional [religious] beliefs. If they think that, apart from these beliefs, there is no reason for kindly behaviour, the results may be needlessly unfortunate. That is why it is important to show that no supernatural reasons are needed to make [people] kind and to prove that only through kindness can the human race achieve happiness.

No Carthaginian denied Moloch, because to do so would have required more courage that was required to face death in battle.

The very best proof that something can be done is that someone has already done it.

He will see himself and life and the world as truly as our human limitations will permit; realizing the brevity and minuteness of human life, he will realize also that in individual minds is concentrated whatever of value the known universe contains.