During the late Edo period, in line with social movements such as rising of kokugaku (study of Japanese literature and culture), critical views against shinbutsushugo (syncretization of Shinto with Buddhism) in which Buddhism and Shintoism were united came up.
江戸時代の後期になると、国学が盛んになるなどの社会の動きに対応して、仏教と神道が結びついた神仏習合に批判的な意見が見られるようになった。