haust the knowledge of nature, is not exclusive and absolute as regards its object, nature. We say for thought, for unless it be seen that, as we have stated, the philosophy of nature presupposes the science of pure thought which is, of course, known only in thought, its existence is not to be comprehended. Of course the natural scientist who is unaware of the existence of a science of thought, cannot be expected to understand how there can be a philosophy of nature which is not identical with his own province of knowledge.
A fuller, more concrete notion of the distinction between the philosophy of nature and natural science may be gained from a comparison of the methods of the two. Natural science is a bringing together into (formal) unity of "given," or passively apprehended, "facts" under, or by means of, certain notions (as those of space, time, motion, number, matter, etc.), which also, as far as it is concerned, are "given." As "given," facts and notions have, of course, in themselves no meaning and have no conceived inner relation to one another as classes, but are brought together only in consequence of a certain instinct, which is not an object of natural science as such, towards unity of apprehension. Consequently the relations apprehended by natural science are relations between rather than in things, external rather than internal, formal rather than constitutive relations; they are subjective, abstract, merely provisional, inexact, instead of objective, concrete, final, exact. The natural sciences even those mathematically grounded are (admittedly) full of mere "symbols," "postulates," "working hypotheses," "analogies," "tentative results," "probabilities," "approximations," etc., etc. For the philosophy of nature nothing is purely, or absolutely, "given," "mere fact"; everything is a product and an expression of (self-determining) thought; those notions of space, time, motion, number, matter, etc., which are mere postulates for natural science, are forms of thought (self-externalized), and the laws of external existence are but higher powers of these. The relations apprehended and determined by the philosophy of nature are internal and constitutive, relations of or in the real being, and not merely in the phenomenal existence
