and Gassendi, with whom I prevailed to explain their systems to Aristotle. This great philosopher freely acknowledged his own mistakes in natural philosophy, because he proceeded in many things upon conjecture, as all men must do; and he found that Gassendi, who had made the doctrine of Epicurus as palatable as he could, and the vortices of Descartes, were equally to be exploded. He predicted the same fate to attraction, whereof the present learned are such zealous asserters. He said, “that new systems of nature were but new fashions, which would vary in every age; and even those, who pretend to demonstrate them from mathematical principles, would flourish but a short period of time, and be out of vogue when that was determined.”

I spent five days in conversing with many others of the ancient learned.