If we love our fellow humans, we cannot limit our insight and our love only to others as individuals...We have to be political people, I would even say passionately involved political people, each of us in the way that best suits our own temperaments, our working lives, and our own capabilities.

The revolutionary and critical thinker is in a certain way always outside of his society while of course he is at the same time also in it.

In our enthusiasm to dominate nature and to produce more material good - goods - we have transformed means into ends.

Knowing means to penetrate through the surface, in order to arrive at the roots, and hence the causes; knowing means to "see" reality in its nakedness. Knowing does not mean to be in the possession of the truth; it means to penetrate the surface and to strive critically and actively in order to approach truth ever more closely.

Human history began as an act of disobedience, and it is not unlikely that it will be terminated by an act of obedience. At this point in history the capacity to doubt, to criticize and to disobey may be all that stands between a future for mankind and the end of civilization.

Care and responsibility are constituent elements of love, but without respect for and knowledge of the beloved person, love deteriorates into domination and possessiveness.

Man's main task in life is to give birth to himself, to become what he potentially is. The most important product of his effort is his own personality.