Pali
Modern scholarship

According to K. R. Norman, differences between different texts within the canon suggest that it contains material from more than a single dialect. He also suggests it is likely that the viharas in North India had separate collections of material, preserved in the local dialect. In the early period it is likely that no degree of translation was necessary in communicating this material to other areas. Around the time of Ashoka there had been more linguistic divergence, and an attempt was made to assemble all the material. It is possible that a language quite close to the Pali of the canon emerged as a result of this process as a compromise of the various dialects in which the earliest material had been preserved, and this language functioned as a lingua franca among Eastern Buddhists from then on. Following this period, the language underwent a small degree of Sanskritisation (i.e., MIA bamhana > brahmana, tta > tva in some cases).

Bhikkhu Bodhi, summarizing the current state of scholarship, states that the language is "closely related to the language (or, more likely, the various regional dialects) that the Buddha himself spoke". He goes on to write:

Scholars regard this language as a hybrid showing features of several Prakrit dialects used around the third century BCE, subjected to a partial process of Sanskritization. While the language is not identical to what Buddha himself would have spoken, it belongs to the same broad language family as those he might have used and originates from the same conceptual matrix. This language thus reflects the thought-world that the Buddha inherited from the wider Indian culture into which he was born, so that its words capture the subtle nuances of that thought-world.

According to A. K. Warder, the Pali language is a Prakrit language used in a region of Western India. Warder associates Pali with the Indian realm (janapada) of Avanti, where the Sthavira nikāya was centered. Following the initial split in the Buddhist community, the Sthavira nikāya became influential in Western and South India while the Mahāsāṃghika branch became influential in Central and East India. Akira Hirakawa and Paul Groner also associate Pali with Western India and the Sthavira nikāya, citing the Saurashtran inscriptions, which are linguistically closest to the Pali language.
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