成唯識論述記 2.482

2.482

述曰：此五色根非現量得，亦非現世人所共知。此眼、耳等，各由彼彼有發識用，比知是有。言「證知」者，證成道理也，以現見果比有因故，果謂所生心、心所法，比量知有清淨色根，此非現量，他心智知。然今大乘第八識境，亦現量得，佛智緣時亦現量緣，今就他部，除佛以外，共許為論，非世共悉，是故但言比知是有。

The Commentary states: These five material sense-faculties are not apprehended by direct perception, nor are they commonly known by worldly people. These eyes, ears, and so forth are each inferred to exist from their function of initiating consciousness. "Proven to exist" refers to the principle of establishing proof: because an effect is presently seen, a cause is inferred to exist; the effect refers to the produced mind and mental factors, by which pure material sense-faculties are known to exist through inference; they are not known through direct perception or by the knowledge of others' minds. However, in our Mahāyāna, the objects of the eighth consciousness are also apprehended by direct perception, and when the Buddha's wisdom cognizes them, it also cognizes them by direct perception. Now, addressing other schools, excluding the Buddha, we argue in terms of what is mutually accepted; since it is not known to the worldly, it is only said to be known to exist by inference.