因明入正理論疏 3.195

3.195

問：「若爾，現量、比量及念，俱非比量智之正體，何名比量？」答：「此三能為比量之智近、遠生因，因從果名。故《理門》云：『是近是遠，比量因故，俱名比量。』又云：『此依作具、作者而說。』如似伐樹，斧等為作具，人為作者，彼樹得倒，人為近因，斧為遠因。有云：『斧親斷樹為近因，人持於斧疎，非親因。』此現、比量為作具，憶因之念為作者。或復翻此，避前二釋，故名比量。」

Question: 'If so, perception, inference, and memory are all not the primary substance of inferential cognition; why are they called inference?' Answer: 'These three can serve as the proximate and remote productive causes for the cognition of inference, and the cause receives the name of the result. Thus the Nyāyamukha states: "Because they are proximate and remote causes of inference, they are both called inference." It also says: "This is stated in terms of the instrument (karaṇa) and the agent (kartṛ)." Just like felling a tree, an axe and the like are the instrument, and the person is the agent; for that tree to be felled, the person is the proximate cause, and the axe is the remote cause. Some say: "The axe directly cuts the tree and is the proximate cause; the person holding the axe is distant and not the direct cause." Here, perception and inference are the instrument, and the memory of the reason is the agent. Or conversely, avoiding the previous two explanations, it is therefore called inference.'