成唯識論述記 4.631

4.631

述曰：論主難云：若心不滅故言不爾，如何名為無心定也？此中心應滅，名所無心故，如受、想。受、想名為滅受想定，此二即無，心例亦應爾，名無心定故。

The Commentary states: The author of the treatise objects: If mind does not cease, and you therefore say it is not so, how could it be called a mindless attainment? In this [attainment], mind should cease, because it is named after the mind that is absent, just as with feeling and conception. Feeling and conception give it the name 'attainment of the cessation of feeling and conception,' and these two are absent; by analogy, mind should also be like this, because it is called 'mindless attainment.'