However, there were suspicions that the books may be fake due to the circumstances in which they were rediscovered, and during the Tang Dynasty, two distinct schools were formed—the 'Kobun' school and the 'Kinbun' school—as a result of a difference in opinion regarding which was the authentic "Kokyo" book, with both accused the other of following a 'forged book.'
ところが、「古文」・「今文」ともに再発見の経緯から「偽書」であるとする疑惑を抱えており、特に唐代に入ると、どちらを『孝経』の正本と考えるかという認識の違いから、「古文」派と「今文」派に分かれて相手の系統を「偽書」とする攻撃を繰り返した。