However, in Buddhist Studies, it is pointed out that there is not much of a basis behind the esan kiitsu because although the Lotus Sutra set a goal of 'learning ichijo through understanding sanjo,' it is not clearly explained how these different people can be treated equally in accordance with the preaching of ichijo, in addition to the fact that there is an academic theory that the Lotus Sutra has no content.
しかし、仏教学においては法華経無内容説という学説的な主張に加え、また法華経が「三乗を会して一乗に帰す」という目標を示してはいるものの、三乗の差別ある者たちがどうやって一乗の教えに平等に帰すことができるのか明らかに説かれておらず、その根拠に乏しいという指摘もある。