Every new system of philosophy, however original in appearance, is more or less directly related to the doctrines which have preceded it. But it is also connected with more general conditions in a manner no less close, if not so immediately obvious. It depends upon a whole set of social conditions. The influence of the religious, political, economical, intellectual phenomena, in a word of the contemporary milieu upon this system is as indisputable as its own influence upon the milieu. It is therefore not enough to study it as a self-sufficient whole. This whole which is in itself but a part, must be restored to its place within the greater whole which alone explains its essential characteristics.