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Scholars' opinion on historicity
The accounts of the texts specific to the Mahayana school (the Mahayana Sutras) are seen by scholars to not represent a true historic account of the life and teachings of Buddha. The traditional account of why these accounts are not preserved in the older Tripitaka texts (the Pali Canon and the Agamas) of Early Buddhism, invariably involve stories of mythical dragons (Nāgas) and denigrating accounts on the intelligence of humankind (not clever enough) at the time of the Buddha. The scholar A. K. Warder gives the following reasons for not accepting the Mahayana Sutras as giving a historical account of events in the life of Gautama Buddha:
It is a curious aspersion on the powers of the Buddha that he failed to do what others were able to accomplish 600 years later.
Linguistically and stylistically the Mahayana texts belong to a later stratum of Indian literature than the Tripitaka known to the early schools.
Everything about early Buddhism, and even the Mahayana itself (with the exception of the Mantrayana), suggests that it was a teaching not meant to be kept secret but intended to be published to all the world, to spread enlightenment.
We are on safe ground only with those texts the authenticity of which is admitted by all schools of Buddhism (including the Mahayana, who admit the authenticity of the early canons as well as their own texts), not with texts accepted only by certain schools.
Mahayana developed gradually out of one, or a group, of the eighteen early schools, and originally it took its stand not primarily on any new texts but on its own interpretations of the universally recognised Tripitaka.
The scholar John W. Pettit, while agreeing that "Mahayana has not got a strong historical claim for representing the explicit teachings of the historical Buddha", also argues that the basic concepts of Mahayana do occur in the Pali Canon and that this suggests that Mahayana is "not simply an accretion of fabricated doctrines" but "has a strong connection with the teachings of Buddha himself"..
A striking example of the differences between the Mahayana literature and at least some of the Pali/agama literature is seen in a comparison of two different texts with the same title: the Mahaparinibbana Sutta of the Pali Canon (referred to here by its Pali title) and the Mahayana Mahaparinirvana Sutra (referred to by its Sanskrit title):
The Pali Mahaparinibbana Sutta is biographical; it gives an account of the events surrounding the end of the Buddha's life, of which scholars have said that it displays attention to detail and has been resorted to as the principal source of reference in most standard studies of the Buddha's life.
The Mahayana Mahaparinirvana Sutra takes the events of the last period of the Buddha's life, and uses them as a setting for an extended religious discourse. It displays a disregard for historic particulars and a fascination with the supernatural..
It should be noted that the weak claim to historicity that the Mahayana Sutras hold, doesn't mean that all scholars believe that the Pali Canon is historical; some scholars believe that it is not
Does a sutra have to be historical to be read or to work?
Does stating that only Buddha's historical sutras have any place in being accepted ignorant of his teachings that he is "amatta" or attained the deathless state and therefore can be accessed even when he has left his "historical body" and can continue to be heard by the faithful?