The chief source of man's inhumanity to man seems to be the tribal limits of his sense of obligation to other men.
Reinhold NiebuhrOur dreams of bringing the whole of human history under the control of the human will are ironically refuted by the fact that no group of idealists can easily move the pattern of history toward the desired goal of peace and justice. The recalcitrant forces in the historical drama have a power and persistence beyond our reckoning.
Reinhold NiebuhrThe society in which each man lives is at once the basis for, and the nemesis of, that fulness of life which each man seeks.
Reinhold NiebuhrThe scientific observer of the realm of nature is in a sense naturally and inevitably disinterested. At least, nothing in the natural scene can arouse his bias. Furthermore, he stands completely outside of the natural so that his mind, whatever his limitations, approximates pure mind. The observer of the realm of history cannot be disinterested in the same way, for two reasons: first, he must look at history from some locus in history; secondly, he is to a certain degree engaged in its ideological conflicts.
Reinhold Niebuhr