Explain the extent to which this excerpt of Buddha’s “Setting in Motion the Wheel of Law [Dharma]” is a reliable source of evidence about the teachings of Siddhartha Gautama

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Excerpt 1 from “Setting in Motion the Wheel of the Law[Dharma]” from the Tripitaka

And the Blessed One thus addressed the five Bhikkhus [men that later became Buddha’s followers]: 'There are two extremes, O Bhikkhus, which he who has given up the world, ought to avoid. What are these two extremes? A life given to pleasures, devoted to pleasures and lusts: this is degrading, sensual, vulgar, ignoble [shameful], and profitless; and a life given to mortifications: this is painful, ignoble, and profitless. By avoiding these two extremes, O Bhikkhus, the Tathâgata has gained the knowledge of the Middle Path which leads to insight, which leads to wisdom, which conduces to calm, to knowledge, to the Sambodhi, to Nirvâna.

Explain the extent to which this excerpt of Buddha’s “Setting in Motion the Wheel of Law [Dharma]” is a reliable source of evidence about the teachings of Siddhartha Gautama.

The reliability of “Setting in Motion the Wheel of Law [Dharma]” as a source of evidence about Buddha´s teachings can be questioned because it was inscribed two hundred years later in the Three Baskets of Wisdom, after being shared orally by Buddhists.

Explanation:

Beginning with the five Bhikkhus who received the message, that oral tradition, the content might have changed or become reinterpreted by those sharing it.