It is sometimes said that we live in an age that rejects authority. The statement, thus qualified, seems misleading; probably there never was a time … - Henry Sidgwick

A universal refusal to propagate the human species would be the greatest of conceivable crimes from a Utilitarian point of view

Now, I agree with Mill in holding that the scientific study of the structures and functions of the different governments that have actually existed in human societies cannot well be pursued in complete separation from the scientific study of other important elements of the societies in question: whether the aim of the student is to ascertain the causes of the differences in such governments or to examine their effects. But I do not think that there is any fundamental difference, in this respect, between the study of political relations and the study of economic relations, or, again, of religion, of art, of science and philosophy, as factors of social life. In each of these eases the student concentrates his attention on one element of human history which can only be partially separated from other components of the whole complex fact of social development. Experience seems to show that this kind of concentration, and consequent partial separation of historical and sociological study into special branches, is unavoidable in the division of intellectual labour which the growth of our knowledge renders necessary in a continually increasing degree.

How far we are to consider the interests of posterity when they seem to conflict with those of now-existing human beings? The answer to this, though, seems clear: the time at which a man exists can’t affect the value of his happiness from a universal point of view; so the interests of posterity must concern a utilitarian as much as those of his contemporaries—except in that the effect of his actions on the lives and even the existence of posterity must be more uncertain.