Humanism, both in its Christian religious and in its secular, non-theistic manifestations, is characterized by faith in man, in his possibility to develop to ever higher stages, in the unity of the human race, in tolerance and peace, and in reason and love as the forces which enable man to realize himself, to become what he can be. ― (1963f: Humanism and Psychoanalysis, in: Contemporary Psychoanalysis, New York he Academic Press, Inc.), Vol. 1 (1964).

Humanist philosophy can be characterized as follows: first, belief in the unity of the human race, that there is nothing human which is not found in every one of us; second, the emphasis on man’s dignity; third, the emphasis on man’s capacity to develop and perfect himself; and fourth, the emphasis on reason, objectivity, and peace. ― (1966i: A Global Philosophy of Man, in: The Humanist, Ohio (American Humanist Association), Vol. 26 (1966), p. 117.)

Humanism has always emerged as a reaction to a threat to mankind: in the Renaissance, to the threat of religious fanaticism; in the Enlightenment, to extreme nationalism and the enslavement of man by the machine and economic interests. The revival of Humanism today is a new reaction to this latter threat in a more intensified form – the fear that man may become the slave of things, the prisoner of circumstances he himself has created – and the wholly new threat to mankind’s physical existence posed by nuclear weapons. ― (1965b: Introduction, in: Socialist Humanism. An International Symposium, ed. by Erich Fromm, Garden City (Anchor Books, Doubleday) 1966, p. VIII.)