Shin Megami Tensei If..., stylized as Shin Megami Tensei if…, is a role-playing video game developed and published by Atlus in 1994 for the Super Famicom. It is a spin-off from the Shin Megami Tensei series, itself part of the larger Megami Tensei franchise. Since release, it has been ported to mobile devices, PlayStation and Microsoft Windows; it had also been re-released on the Virtual Console in Japan on Wii in 2011 and Wii U in 2013, as well as Nintendo Switch Online in 2021. The story follows a student of Karukozaka High School after their school is sucked into the realm of demons by a vengeful student's demon summoning spell going wrong.

Katsuhiko Sato is a Japanese physicist and Special University Professor, emeritus, the University of Tokyo.