But apart from the fact that the highly gifted and unhappy Servetus, whom Calvin burned, had, between 1530 and 1540, made the discovery and lectured upon it, all men of culture in England knew very well before Harvey's time that the blood flowed, even that it circulated, and, more particularly, that it was driven from the heart to the different limbs and organs; only, it was generally conceived that the blood passed from the heart through the veins, and not, as is actually the case, through the arteries. And there is nothing in the seventy-odd places in Shakespeare where the circulation of the blood is mentioned to show that he possessed this ultimate insight, although his general understanding of these questions bears witness to his high culture. Another point which some people have held inexplicable, except by the Baconian theory, may be stated thus: Although the law of gravitation was first discovered by Newton, who was born in 1642, or fully twenty-six years after Shakespeare's death, and although the general conception of gravitation towards the centre of the earth had been unknown before Kepler, who discovered his third law of the mechanism of the heavenly bodies two years after Shakespeare's death, nevertheless in _Troilus and Cressida_ (iv. 2) the heroine thus expresses herself:-- "Time, force, and death, Do to this body what extremes you can, But the strong base and building of my love Is as the very centre of the earth, Drawing all things to it." So carelessly does Shakespeare throw out such an extraordinary divination. His achievement in thus, as it were, rivalling Newton may seem in a certain sense even more extraordinary than Goethe's botanical and osteological discoveries; for Goethe had enjoyed a very different education from his, and had, moreover, all desirable leisure for scientific research. But Newton cannot rightly be said to have discovered the law of gravitation; he only applied it to the movements of the heavenly bodies. Even Aristotle had defined weight as "the striving of heavy bodies towards the centre of the earth." Among men of classical culture in England in Shakespeare's time, the knowledge that the centre point of the earth attracts everything to it was quite common. The passage cited only affords an additional proof that several of the men whose society Shakespeare frequented were among the most highly-developed intellects of the period. That his astronomical knowledge was not, on the whole, in advance of his time is proved by the expression, "the glorious planet Sol" in _Troilus and Cressida_ (i. 3). He never got beyond the Ptolemaic system.