The purpose of this text is to give insight into the main tenets of critical Buddhism (hihan bukkyō) - a Japanese Buddhist reformatory movement from the end of the 20th century. Critical Buddhism aimed at eradicating those doctrinal elements of Japanese Buddhism which were accused of creating a basis for discrimination of certain social groups. Critical Buddhism is presented as having three main aspects: social, doctrinal, and methodological. The first part of the article provides a general introduction to the problem and briefly surveys the doctrinal aspect (hihan bukkyō as "critical philosophy" opposing "topical philosophy"), also adding some remarks on the "sectarian" aspect, i.e., Critical Buddhism as an alternative reading and apology of Dōgen’s doctrinal and social attitude. Next follows an in-depth analysis of the movement’s social aspect - crucial for understanding its motivations. It focuses on the beginnings of critical Buddhism as part of a social and academic movement aimed at tracing the causes of discrimination of some social groups (burakumin, the handicapped, the mentally ill) by the Japanese Zen Sōtō school. Further study of the doctrinal aspect is then deepened by a thorough presentation of Shirō Matsumoto’s critique of doctrines, which he deems antithetical to Buddhism’s main criteria of orthodoxy - the law of pratītyasamutpāda and the notion of anātman. The idea of Buddha-nature (foxing) and that of original awakening (hongaku) are considered by Matsumoto to be non-Buddhist, because they posit the existence of an eternal substance, much like the ātman-brahman of the Upaniṣads. Through textual analysis of some classical Buddhist and Hindu texts Matsumoto shows how those ideas have provided a doctrinal basis for social injustice.