From the Letter to Pythocles:
Quote[95] For on earth too we see many things shining with their own, and many with reflected light. Nor is any celestial phenomenon against these explanations, if one always remembers the method of manifold causes and investigates hypotheses and explanations consistent with them, and does not look to inconsistent notions and emphasize them without cause and so fall back in different ways on different occasions on the method of the single cause.
Epicurus' Letter to Pythocles - Epicureanfriends.com
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