Is the solution simply to invoke the human factor? Humanisms too are subject to rapid change. What remains of Renaissance humanism after man’s great disillusionment through a series of humiliations? The first came when Copernicus showed that Man’s earth was not the centre of the universe; the second when Marx showed how dependent man is on inhuman social conditions; the third when Darwin described man’s origin from the subhuman world; and the fourth was Freud’s explanation of man’s intellectual consciousness as rooted in the instinctive unconscious. … That is to say nothing of fascism and Nazism … fascinated by Nietzsche’s superman … which cost mankind an unparalleled destruction of human values and millions of human lives. In view of this situation, after so many disappointments, a certain scepticism in regard to humanism is understandable.
Hans Küng, On Being a Christian