http://www.swamij.com/yoga-sutras-10511.htm#1.7
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Yoga Sutra 1.7: Of these five, there are three ways of gaining correct knowledge (pramana): 1) perception, 2) inference, and 3) testimony or verbal communication from others who have knowledge.
(pratyaksha anumana agamah pramanani)
pratyaksha = direct perception or cognition
anumana = inference, reasoning, deduction
agamah = authority, testimony, validation, competent evidence
pramanani = valid means of knowing, proofs, sources of correct knowing
Introduction to Yoga Sutras:
http://www.swamij.com/yoga-sutras-intro.htm
Yoga Sutras Table of Sutras:
http://www.swamij.com/yoga-sutras.htm
Yoga Sutras List of Sutras:
http://www.swamij.com/yoga-sutras-list.htm
Yoga Sutras in Narrative:
http://www.swamij.com/yoga-sutras-narrative.htm
Chapters Outline of Yoga Sutras:
http://www.swamij.com/yoga-sutras-ch1.htm
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