things, they must first have acted upon me as motives. I have entered fully into all that has to do with this in my chief work,[264] and in the second edition of my treatise on the Principle of Sufficient Reason, § 21,[265] where the assumption adopted by Herschel finds special refutation; it is therefore useless to enter into it once more here. But it would be even quite possible to refute this assumption empirically, since it would necessarily follow from it, that a man who came into the world without arms or legs, could never attain any knowledge of causality or perception of the outer world. Now Nature has effectually disproved this by a case, of which I have reproduced the account from its original source in the above-mentioned chapter of my chief work, p. 40.[266]--In this assertion of Herschel's therefore, we have another instance of a right conclusion drawn from wrong premisses. Now this always happens when we have obtained immediate insight into a truth by a right _aperçu_ but are at a loss to find out and clearly define our reasons for knowing it, owing to our inability to bring them to clear consciousness. For, in all original insight, conviction exists before proof: the proof being invariably excogitated afterwards. [263] Which he has more at heart than all the wisdom and truth in the world. [Add. to 3rd ed.] [264] See "Die Welt a. W, u. V." vol. ii. ch. 4, pp. 38-42 (3rd edition, pp. 41-46). [265] P. 74 (3rd edition, p. 79), p. 92 of the translation in the present volume. [266] 3rd edition, p. 44. The immediate manifestation of gravity is more evident in each part of liquid, than of solid, matter, owing to the perfect freedom of motion of the parts among each other. In order therefore to penetrate into this _aperçu_, which is the true source of Herschel's assertion, let us look attentively at a torrent dashing headlong over rocks and ask ourselves whether so determined an impetus, so boisterous a vehemence, can arise without an exertion of strength, and whether an exertion of strength is conceivable without will. And so it is precisely in every case in which we become aware of anything moving spontaneously, of any primary, uncommunicated force: we are constrained to think its innermost essence as will.--This much at any rate is certain, that Herschel, like all the empiricists in so many different branches of science whose evidence I have quoted above, had arrived here at the limit where nothing more is left behind the Physical but the Metaphysical; that this had brought him to a standstill, and that he, as well as the rest of them, was unable to find anything beyond that limit, but the _will_. Herschel moreover, like most of these empiricists, is here still hampered by the opinion that will is inseparable from consciousness. As I have expatiated enough above upon this fallacy, and its correction through my doctrine, it is needless for me to enter into it here again.