成唯識論述記 4.911

4.911

述曰：總例餘識令八有根。量云：第八之識有但有根；與餘七識同識性故；如餘七識。此即對前，次前師故得為因也。若對初師即第七識為不定過，以彼不許有此依故。前師問曰：前七別依已如前辨，前第八所依謂以何法？

[The Commentary states:] He generally analogizes it to the other consciousnesses to make the eighth have a sense-faculty. The syllogism is: The eighth consciousness has a sense-faculty; because its nature is identical with the other seven consciousnesses in being a consciousness; like the other seven consciousnesses. This forms a valid reason against the preceding, immediately prior master. If it were against the first master, the seventh consciousness would incur the fallacy of uncertainty, since that master does not accept that it has such a support. The previous master asks: The distinct supports of the prior seven have already been differentiated as before; what dharma is asserted to be the support of the eighth?