成唯識論述記 4.27

4.27

述曰：由此執受五色根故，五識得轉。即顯此識展轉為依。若不執持其五根者，識不得依，如死人等。故說為緣，亦有種依。然是因緣，今約五根增上共許，顯處說故。釋「意識」者。

The Commentary states: Because it appropriates the five corporeal faculties, the five consciousnesses can operate. That is, it shows that this consciousness serves as support indirectly. If it did not hold the five faculties, consciousness would not be able to rely on them, like a corpse and so forth. Therefore it is spoken of as a condition; it also has a seed-support. However, that is a cause-condition; now it is discussed in terms of the predominant condition of the five faculties, which is mutually accepted, as an evident matter. Next, it explains the "mental consciousness."