"What great philosophers do for us is not to hand out such an all-purpose system. It is to light up and clarify some special aspect of life, to supply conceptual tools which will do a certain necessary kind of work. Wide though that area of work may be, it is never the whole, and all ideas lose their proper power when they are used out of their appropriate context. That is why one great philosopher does not necessarily displace another, why there is room for all of them and a great many more whom we do not have yet."