Early Buddhist schools

The early Buddhist schools are those schools into which the Buddhist monastic saṅgha initially split, due originally to differences in vinaya and later also due to doctrinal differences and geographical separation of groups of monks.

The original saṅgha split into the first early schools (generally believed to be the Sthavira nikāya and the Mahāsāṃghika) a significant number of years after the passing away of Gautama Buddha. According to scholar Collett Cox "most scholars would agree that even though the roots of the earliest recognized groups predate Aśoka, their actual separation did not occur until after his death." Later, these first early schools split into further divisions such as the Sarvāstivādins and the Dharmaguptakas, and ended up numbering, traditionally, about 18 or 20 schools. In fact, there are several overlapping lists of 18 schools preserved in the Buddhist tradition, totaling about twice as many, though some may be alternative names. It is thought likely that the number is merely conventional.

According to the scriptures (Cullavagga XI.1 ff), three months after the passing of Gautama Buddha, the first council was held at Rajagaha by some of his disciples who had attained arahantship. At this point, Theravāda tradition maintains that no conflict about what the Buddha taught occurred; the teachings were divided into various parts and each was assigned to an elder and his pupils to commit to memory.

The accounts of the council in the scriptures of the schools differ as to what was actually recited there. Purāṇa is recorded as having said: "Your reverences, well chanted by the elders are the Dhamma and Vinaya, but in that way that I heard it in the Lord's presence, that I received it in his presence, in that same way will I bear it in mind." [Vinaya-pitaka: Cullavagga XI:1:11].

Some scholars deny that the first council actually took place.

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