A person's genetic endowment, a product of the evolution of the species, is said to explain part of the workings of his mind and his personal history the rest.

We admire people to the extent that we cannot explain what they do, and the word 'admire' then means 'marvel at.'

I will be dead in a few months. But it hasn't given me the slightest anxiety or worry. I always knew I was going to die.

We have not yet seen what man can make of man.

The extent to which human aggression exemplifies innate tendencies is not clear.

The problem of far greater importance remains to be solved. Rather than build a world in which we shall all live well, we must stop building one in which it will be impossible to live at all.

The consequences of an act affect the probability of its occurring again.