Shimomura Toratarō was a Japanese philosopher of science belonging to the Kyoto School, who completed his treatises on the philosophy of science primarily during World War II. His philosophy of science centered on mathematics, especially on the theory of the infinite, and discussed not the “history of mathematics” but the history toward mathematics and the history toward science. His philosophy of science was to apply Nishida Kitarō’s “universal world”(「世界的世界」)to set theory, but he also showed an interest in classical and modern physics. This chapter considers the significance of Shimomura’s philosophy of science while focusing on its relationship with physics.