成唯識論述記 5.851

5.851

述曰：言說因相者，謂如前第三卷八識中說。取境分齊相故，謂此是青，非非青等，便起言說，故想之相言，說因也。思了正因等者，謂正因、邪因、俱相違等，即是境上正邪等相，業之因也。此中一一如作意說，亦取別相。何以知心所亦取總相？

The Commentary states: 'The marks of the causes of conventional designation' means what was said previously in the third fascicle regarding the eight consciousnesses: because it grasps the demarcated marks of the object, judging 'this is blue, not non-blue,' and so forth, conventional designation is then aroused; hence the mark of saṃjñā is the cause of conventional designation. 'Cetanā cognizes right causes and so forth' means right cause, wrong cause, neither cause, etc., which are precisely the marks of righteousness, wrongness, and so forth upon the object, being the causes of karma. Each of these, as explained for attention, also grasps specific marks. How is it known that caitasikas also grasp the general mark?