ABSTRACT
The function of knowledge is practical, to guide action. The success of the human species, the sole known society of knowers, in half a million years suffices to demonstrate that sufficient knowledge is attainable. Yet the practical results, however long delayed, provide the sole conclusive test of the truth of the discovery, the proof that it is a contribution to knowledge and not just a new superstition. The unknowable is as irrelevant to the active quest for knowledge, the collection, classification and interpretation of messages received through sense perception as to more practical kinds of action. Imagination is thus conditioned by experience and can only just advance the boundaries of knowledge a small step. The reproduction, termed knowledge, based on experience, on messages received from the external world, can only correspond to the structure of that world in so far as the latter is already realized.
