Page:Popular Science Monthly Volume 5.djvu/309

Rh of his speculations until another great scientific advance had been accomplished. We cannot state his antecedents better than in his own words:

"The beginning of astronomy, except observations, I think, is not to be derived from farther time than from Nicolaus Copernicus, who, in the age next preceding the present, revived the opinion of Pythagoras, Aristarchus, and Philolaus. After him, the doctrine of the motion of the earth being now received, and a difficult question thereupon arising concerning the descent of heavy bodies, Galileus in our time, striving with that difficulty, was the first that opened to us the gate of natural philosophy universal, which is the knowledge of the nature of motion. So that neither can the age of natural philosophy be reckoned higher than to him. Lastly, the science of man's body, the most profitable part of natural science, was first discovered with admirable sagacity by our countryman. Dr. Harvey, principal physician to King James and King Charles, in his books of the 'Motion of the Blood' and of the 'Generation of Living Creatures;' who is the only man I know that, conquering envy, hath established a new doctrine in his lifetime. Before these, there was nothing certain in natural philosophy, but every man's experiments to himself, and the natural histories, if they may be called certain, that are no certainer than civil histories. But since these, astronomy and natural philosophy have, for so little time, been extraordinarily advanced by Joannes Keplerus, Petrus Gassendus, and Marinus Mersennus; and the science of human bodies in special by the wit and industry of physicians, the only true natural philosophers, especially of our most learned men of the College of Physicians in London. Natural Philosophy is therefore but young; but Civil Philosophy yet much younger, as being no older (I say it provoked, and that my detractors may know how little they have wrought upon me) than my own book, De Cive (the Citizen.)"

The application of all this to the psychological philosophy of Hobbes is so patent as hardly to need elucidation in detail. Like his contemporary Descartes, Hobbes was extremely jealous of his independence, and, what was of less consequence, his originality; and one may even now hear, not without surprise and otherwise, the unlucky epigram which makes him say that, if he had read as many books as other people, he would have been as ignorant as they. Hobbes had read a great deal more than he deemed it prudent to admit, and if he had read more still the good effect of it would not have been doubtful. But, like the Greeks in the time of Sophocles, he had an advantage which would have made up for any deficiency of literary acquisition. He lived in an atmosphere heavy with ideas, and at a time when epistolary communication performed the functions very much which scientific journals now fulfill. Hobbes does not appear to have corresponded with Descartes, but he was in constant intercourse, by letter, with Mersenne, who acted as the intermediary between the two philosophers. And, as philosophers then concerned themselves with the whole range of the sciences, there was hardly a speculation stirring the European mind that need have escaped the notice of even a