We have hitherto spoken chiefly of the manner in which Linnaeus dealt with his subject in matters of detail; in his inner nature he was a schoolman, and that in a higher degree than even Cesalpino himself, who should rather be called an Aristotelian in the strict sense of the word. But to say that Linnaeus’ mode of thought is thoroughly scholastic is virtually saying that he was not an investigator of nature in the modern meaning of the word; we might point to the fact that Linnaeus never made a single important discovery throwing light on the nature of the vegetable world; but that would still not prove that he was a schoolman. True investigation of nature consists not only in deducing rules from exact and comparative observation of the phenomena of nature, but in discovering the genetic forces from which the causal connexion, cause and effect may be derived. In the pursuit of these objects, it is compelled to be constantly correcting existing conceptions and theories, producing new conceptions and new theories, and thus adjusting our own ideas more and more to the nature of things. The understanding does not prescribe to the objects, but the objects to the understanding. The Aristotelian philosophy and its medieval form, scholasticism, proceeds in exactly the contrary way; it is not properly concerned with acquiring new conceptions and new theories by means of investigation, for conceptions and theories have been once for all established; experience must conform itself to the ready-made system of thought; whatever does not so conform must be dialectically twisted and explained till it apparently fits in with the whole. From this point of view the intellectual task consists essentially in this twisting and turning of facts, for the general idea of the whole is already made and needs not to be altered. Experience in the higher sense of investigation of nature is rendered impossible by the fact, that we are supposed to know all the ultimate principles of things; but these ultimate principles of scholasticism are at bottom only words with extremely indefinite meaning, abstractions obtained by a series of jumps from every-day experience, which has not been tried and refined in the crucible of science, and is therefore worthless; and the higher the abstraction is raised, the farther it withdraws from the guiding hand of experience, the more venerable and more important do these ‘abstracta’ appear, and we can finally come to a mutual understanding about them, though again only through figures and metaphors[29]. Science, according to the scholastic method, is a playing with abstract conceptions; the best player is he who can so combine them together, that the real contradictions are skilfully concealed. On the contrary, the object of true investigation, whether in philosophy or in natural science, is to make unsparing discovery of existing contradictions and to question the facts until our conceptions are cleared up, and if