History of Western Philosophy - Bertrand Russell [317]
I said that Descartes was a timid man, but perhaps it would be kinder to say that he wished to be left in peace so as to do his work undisturbed. He always courted ecclesiastics, especially Jesuits—not only while he was in their power, but after his emigration to Holland. His psychology is obscure, but I incline to think that he was a sincere Catholic, and wished to persuade the Church—in its own interests as well as in his—to be less hostile to modern science than it showed itself in the case of Galileo. There are those who think that his orthodoxy was merely politic, but though this is a possible view I do not think it the most probable.
Even in Holland he was subject to vexatious attacks, not by the Roman Church, but by Protestant bigots. It was said that his views led to atheism, and he would have been prosecuted but for the intervention of the French ambassador and the Prince of Orange. This attack having failed, another, less direct, was made a few years later by the authorities of the University of Leyden, which forbade all mention of him, whether favourable or unfavourable. Again the Prince of Orange intervened, and told the university not to be silly. This illustrates the gain to Protestant countries from the subordination of the Church to the State, and from the comparative weakness of Churches that were not international.
Unfortunately, through Chanut, the French ambassador at Stockholm, Descartes got into correspondence with Queen Christina of Sweden, a passionate and learned lady who thought that, as a sovereign, she had a right to waste the time of great men. He sent her a treatise on love, a subject which until then he had somewhat neglected. He also sent her a work on the passions of the soul, which he had originally composed for Princess Elizabeth, daughter of the Elector Palatine. These writings led her to request his presence at her court; he at last agreed, and she sent a warship to fetch him (September, 1649). It turned out that she wanted daily lessons from him, but could not spare the time except at five in the morning. This unaccustomed early rising, in the cold of a Scandinavian winter, was not the best thing for a delicate man. Moreover, Chanut became dangerously ill, and Descartes looked after him. The ambassador recovered, but Descartes fell ill and died in February, 1650.
Descartes never married, but he had a natural daughter who died at the age of five; this was, he said, the greatest sorrow of his life. He always was well dressed, and wore a sword. He was not industrious; he worked short hours, and read little. When he went to Holland he took few books with him, but among them were the Bible and Thomas Aquinas. His work seems to have been done with great concentration during short periods; but perhaps, to keep up the appearance of a gentlemanly amateur, he may have pretended to work less than in fact he did, for otherwise his achievements seem scarcely credible.
Descartes was a philosopher, a mathematician, and a man of science. In philosophy and mathematics, his work was of supreme importance; in science, though creditable, it was not so good as that of some of his contemporaries.
His great contribution to geometry was the invention of co-ordinate geometry, though not quite in its final form. He used the analytic method, which supposes a problem solved, and examines the consequences of the supposition; and he applied algebra to geometry. In both of these he had had predecessors—as regards the former, even among the ancients. What was original in him was the use of co-ordinates, i.e. the determination of the position of a point in a plane by its distance from two fixed lines. He did not himself discover all the power of this method, but he did enough to make further progress easy. This was by no means his sole contribution to mathematics, but it was his most important.
The book in which he set forth most of his scientific theories was Principia Philosophiae,