成唯識論述記 5.492

5.492

述曰：義雖不然，汝之五識，亦應許有無依之時；六識攝故；如汝意識。此有自宗相違過失，以就他宗，然成返難。五識恒有依，意識應亦爾，結成前難。

The Commentary states: Although the meaning is not so, your five consciousnesses should also be admitted to have times when they lack a support; because they are included within the six consciousnesses; like your mental consciousness. This has the fault of contradiction with one's own tenet, but adopting the other's system, it turns into a counter-challenge. The five consciousnesses always have a support; mental consciousness should also be like that—concluding the previous challenge.