This animation, this personification, interpenetrates our very knowledge. "Who is it that sends the rain? Who is it that thunders?" old Strepsiades asks of Socrates in _The Clouds_ of Aristophanes, and the philosopher replies: "Not Zeus, but the clouds." "But," questions Strepsiades, "who but Zeus makes the clouds sweep along?" to which Socrates answers: "Not a bit of it; it is atmospheric whirligig." "Whirligig?" muses Strepsiades; "I never thought of that--that Zeus is gone and that Son Whirligig rules now in his stead." And so the old man goes on personifying and animating the whirlwind, as if the whirlwind were now a king, not without consciousness of his kingship. And in exchanging a Zeus for a whirlwind--God for matter, for example--we all do the same thing. And the reason is because philosophy does not work upon the objective reality which we perceive with the senses, but upon the complex of ideas, images, notions, perceptions, etc., embodied in language and transmitted to us with our language by our ancestors. That which we call the world, the objective world, is a social tradition. It is given to us ready made. Man does not submit to being, as consciousness, alone in the Universe, nor to being merely one objective phenomenon the more. He wishes to save his vital or passional subjectivity by attributing life, personality, spirit, to the whole Universe. In order to realize his wish he has discovered God and substance; God and substance continually reappear in his thought cloaked in different disguises. Because we are conscious, we feel that we exist, which is quite another thing from knowing that we exist, and we wish to feel the existence of everything else; we wish that of all the other individual things each one should also be an "I." The most consistent, although the most incongruous and vacillating, idealism, that of Berkeley, who denied the existence of matter, of something inert and extended and passive, as the cause of our sensations and the substratum of external phenomena, is in its essence nothing but an absolute spiritualism or dynamism, the supposition that every sensation comes to us, causatively, from another spirit--that is, from another consciousness. And his doctrine has a certain affinity with those of Schopenhauer and Hartmann. The former's doctrine of the Will and the latter's doctrine of the Unconscious are already implied in the Berkeleyan theory that to be is to be perceived. To which must be added: and to cause others to perceive what is. Thus the old adage _operari sequitur esse_ (action follows being) must be modified by saying that to be is to act, and only that which acts--the active--exists, and in so far as it acts.