Mathematician and Physicist.
Siméon Denis Poisson (21 June 1781 – 25 April 1840), was a French mathematician, geometer, and physicist. He obtained many important results, but within the elite Académie des Sciences he also was the final leading opponent of the wave theory of light and was proven wrong on that matter by Augustin-Jean Fresnel.
1.) Lorraine Daston (1995). Classical Probability in the Enlightenment. Princeton University Press. p. 381. ISBN 9780691006444. "Poisson's understanding of causes, both natural and moral, was totally agnostic."
2.) "Now Ibn al-Haytham was a devout Muslim – that is, he was a supernaturalist. He studied science because he considered that by doing this he could better understand the nature of the god that he believed in – he thought that a supernatural agent had created the laws of nature. The same is true of virtually all the leading scientists in the Western world, such as Galileo and Newton, who lived after al-Haytham, until about the middle of the twentieth century. There were a few exceptions – Pierre Laplace, Simeon Poisson, Albert Einstein, Paul Dirac and Marie Curie were naturalists for example." John Ellis, How Science Works: Evolution: A Student Primer, page 13.