The earliest known texts of Gotama’s teachings are the Pāli Nikāyas, preserved mainly through the Theravāda Buddhist tradition, the only one still actively practiced today (in Sri Lanka, Thailand, & Myanmar, mostly). We have these monastic traditions to thank for knowledge of these texts. Some parallels in Chinese & Sanskrit exist, as Bhikkhu Anālayo & others have explored; these do not seriously contradict the Pāli. Pāli is believed to be close to, if not matching, the languages that Gotama used; it combines several common languages spoken at that time. As the game of telephone (passing a whispered phrase around a circle) illustrates, earlier texts are most likely closest to the teachings Gotama actually gave. They are not pure, in any sense, but they are the best we have. That being said, there are many helpful teachings given by others following in Gotama’s footsteps, for example Nāgārjuna (2nd century C.E. in South India), sometimes known as “the second Buddha,” & Dōgen (13th century C.E. Japan) in the Zen tradition. However, rigid views & other dogma began to masquerade as Gotama’s teachings even in his own day. A fifth-century text, the Visuddhimagga, attributed to Buddhaghosa, for example, is a tricky mixture of helpful synthesis, unhelpful reification, cultural baggage, & nonsense. The earliest texts provide the best tool—along with meditation practice—for separating cultures, later ideas, & misunderstandings that have become mixed with Gotama’s teachings over time.