The remark of C. G. J. Jacobi that mathematics is slow of growth and only reaches the truth by long and devious paths, that the way to its discovery must be prepared for long beforehand, and that then the truth will make its long-deferred appearance as if impelled by some divine necessity[92]--all this holds true of every science. We are astounded often to note that it required the combined labors of many eminent thinkers for a full century to reach a truth which it takes us only a few hours to master and which once acquired seems extremely easy to reach under the right sort of circumstances. To our humiliation we learn that even the greatest men are born more for life than for science. The extent to which even they are indebted to accident--to that singular conflux of the physical and the psychical life in which the continuous but yet imperfect and never-ending adaptation of the latter to the former finds its distinct expression--that has been the subject of our remarks to-day. Jacobi's poetical thought of a divine necessity acting in science will lose none of its loftiness for us if we discover in this necessity the same power that destroys the unfit and fosters the fit. For loftier, nobler, and more romantic than poetry is the truth and the reality. FOOTNOTES: [Footnote 81: Inaugural lecture delivered on assuming the Professorship of the History and Theory of Inductive Science in the University of Vienna, October 21, 1895.] [Footnote 82: The phrase is, _Er hat das Pulver nicht erfunden_.] [Footnote 83: "Quod si quis tanta industria exstitisset, ut ex naturae principiis at geometria hanc rem eruere potuisset, eum ego supra mortalium sortem ingenio valuisse dicendum crederem. Sed hoc tantum abest, ut fortuito reperti artificii rationem non adhuc satis explicari potuerint viri doctissimi."--Hugenii Dioptrica (de telescopiis).] [Footnote 84: I must not be understood as saying that the fire-drill has played no part in the worship of fire or of the sun.] [Footnote 85: Compare on this point the extremely interesting remarks of Dr. Paul Carus in his _Philosophy of the Tool_, Chicago, 1893.] [Footnote 86: Möbius, _Naturwissenschaftlicher Verein für Schleswig-Holstein_, Kiel, 1893, p. 113 et seq.] [Footnote 87: I am indebted for this observation to Professor Hatscheck.] [Footnote 88: Cf. Hoppe, _Entdecken und Finden_, 1870.] [Footnote 89: See the lecture "Sensations of Orientation," p. 282 et seq.] [Footnote 90: This story was related to me by Jolly, and subsequently repeated in a letter from him.] [Footnote 91: I do not know whether Swift's academy of schemers in Lagado, in which great discoveries and inventions were made by a sort of verbal game of dice, was intended as a satire on Francis Bacon's method of making discoveries by means of huge synoptic tables constructed by scribes. It certainly would not have been ill-placed.]