My life is full of meaning to me. The life around me must be full of significance to itself. If I am to expect others to respect my life, then I must respect the other life I see.

The the question whether I am a pessimist or an optimist, I answer that my knowledge is pessimistic, but my willing and hope are optimistic.

As we acquire knowledge, things do not become more comprehensible, but more mysterious.

The friend of nature is the man who feels himself inwardly united with everything that lives in nature, who shares in the fate of all creatures, helps them when he can in their pain and need, and as far as possible avoids injuring or taking life.

World-view is a product of life-view, not vice versa.

Affirmation of life is the spiritual act by which man ceases to live unreflectively and begins to devote himself to his life with reverence in order to raise it to its true value. To affirm life is to deepen, to make more inward, and to exalt the will.

Anyone who proposes to do good must not expect people to roll stones out of his way, but must accept his lot calmly if they even roll a few more on it. A strength which becomes clearer and stronger through experiences of such obstacles is the only strength that can conquer them. Resistance is only a waste of strength.