The Nature and Evolution of Leonardo's Scientific Mind
There are now many treatises and monographs expounding the detail of Leonardo's scientific researches, based upon modern editing of the countless fragments in the Codex Atlanticus, the MSS. of the Institut de France, the Victoria and Albert MSS., the Windsor anatomical MSS., etc. I am not pretending here to add to these expositions. For the purpose of the present problem their contents are only relevant as far as they contribute to building an estimate of Leonardo's general state of mind and attitude to experience. We need at the beginning to know to what extent he was permeated by the scientific habit. We shall next need to understand how that habit evolved in him and how it affected his art. For these psychological aspects of Leonardo the scientist, Séailles is perhaps the most valuable of the assessors of his investigations, but I will abstract as follows from many authors sufficient for the peculiar bias of the Leonardo mind to emerge.
He was not primarily a mathematician; the note-books reveal large numbers of geometrical diagrams, but fewer calculations or solutions of equations, and almost all of both these were introduced as subsidiary to mechanical problems. Many Renaissance artists were keenly interested in geometry for the sake of perspective, and Leonardo not outstandingly more so than others. Chemistry and chemical metallurgy again interested him mainly as a means for effecting the preparation of substances needed in other sciences and arts. The mechanical and physical sciences, on the other hand, he studied for their own sake. From one of his note-books: 'Mechanics is the paradise of the mathematical sciences because in it we come to the fruits of mathematics.' But he was not a theorist, and when I say that he anticipated the principle of inertia of Galileo and Newton I mean that his notes reveal its unconscious use in attacking particular problems, rather than that he possessed any of the generalising power of a Newton. The notion of equality