QUOTE : Philosophy can be a hypothetical explanation of what is known, or an attempt to guess what is not known. It poses questions which, so far at least, go beyond the competence of science, and suggests answers which, in the present state of our knowledge, cannot be subjected to proof. Thus different philosophers offer divergent, and contradictory solutions. When philosophy is not simply a play on words and an illusionist’s trick, it can be a spur and a guide to science, but it is not science.