Abstract
Kant argues at the beginning of his critical work that transcendental philosophy completely banishes anything that is merely of the order of an hypothesis. Does this rejection reveal his assurance that he, like Newton, makes no hypotheses? Newton’s famous “Hypothesis non fingo” was meant to stem the multiplication of redundant hypotheses in mathematical physics. Thus, according to Newton, a Cartesian vortex dragging material particles into itself does not really explain the motion of the particles. The problem of the origin of their motion has been obscured by Descartes, because the medium happens to move in a way that is indistinguishable from the particles themselves. The point is stressed by Cotes in his preface to the second edition of Newton’s Principia. Suppose the cause of gravity is explained by means of a “subtle matter, not discernible by our sight... or any other of our senses.” Any body that moves in this medium will simply follow the figure already described by the medium. We start from a purely ideal conjecture concerning the non-sensible existence of a vortex, and we end up with the conclusion that “the meanest man may understand” the ultimate causes of nature; that is, we have never really moved away from the superficial level of immediate appearances. As for Newton’s physics itself, recent historiography has shown that numerous worthy hypotheses are used in virtually all of its areas.