Revolution is not the uprising against preexisting order, but the setting up of a new order contradictory to the traditional one

If the human intellect functions, it is actually in order to solve the problems which the man's inner destiny sets it.

One age cannot be completely understood if all the others are not understood. The song of history can only be sung as a whole.

Life is a struggle with things to maintain itself among them. Concepts are the strategic plan we form in answer to the attack.

We cannot put off living until we are ready. The most salient characteristic of life is its urgency, 'here and now' without any possible postponement. Life is fired at us point-blank.

The difficulties which I meet with in order to realize my existence are precisely what awaken and mobilize my activities, my capacities.

The man who discovers a new scientific truth has previously had to smash to atoms almost everything he had learnt, and arrives at the new truth with hands blood stained from the slaughter of a thousand platitudes.