evidence: Immanuel Kant: The A Priori Conditions of the Sciences [...] See Immanuel Kant, Prolegomena to Any Future Metaphysics, ed. Lewis White Beck (Bobbs-Merrill, 1950), §2. [...] Inspired by Newtonian mechanics, Immanuel Kant developed an original hypothesis, which was supposed to explain the origin of the solar system. Kant’s idea, even though it was imprecise and lacked a solid scientific foundation, is worthy of note if only because of its later development in an hypothesis proposed (independently of Kant) by Laplace. In 1755, Kant proposed an hypothesis explaining the origin of planetary systems as well as various stellar systems (which he called "systematic constitutions"). He said that a planetary system arose from a rotating cloud of gas. Inside the whirling cloud, stars, planets, and their moons were formed from the condensation of matter. The main problem with Kant’s theory was the lack of scientific foundation. Further, the theory was not free of imprecision. At the beginning of his cosmogonic speculations, the philosopher of Königsberg accepted some tacit premises, such as the existence of a whirling gas cloud and the assumption that in a whirling gas cloud there really would be a condensation of the dispersed matter.