The Dhammapada
Buddhist canon (attrib. Siddhartha Gautama) · -300
"Suffering originates in the untrained mind — specifically in craving and attachment to things that are inherently impermanent — and the discipline of the mind, not ritual, not belief, not birth, is the entire path out of it."
A compact collection of the Buddha's core teachings in verse form, one of the most widely translated texts in the Pali Buddhist canon. Its opening line sets the frame for the whole text: all that we are is the result of what we have thought — mental states, not external circumstances, are treated as the actual source of both suffering and its end, which makes the mind itself the object of practice rather than any external ritual or deity.
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Tao Te Ching
"The most effective way to live and lead is wu wei — effortless action aligned with the natural grain of things — and force, striving, and the pursuit of recognition are self-defeating compared to yielding, simplicity, and working with rather than against the nature of a situation."