成唯識論述記 7.231

7.231

自下第三解起滅分位。於中有二：初解意常現起；後解除生無想天等。初中二復次解，將明第六常現起故，却結解五識由緣，故生、不生。

From here on, the third section explains the states of arising and cessation. Within this there are two parts: first, explaining that the mind [the sixth consciousness] constantly manifests in active operation; second, explaining the exceptions: being born in the heaven of no-thought, and so forth. In the first part, there are two successive explanations: about to clarify that the sixth constantly manifests in active operation, it turns back to conclude the explanation of why the five consciousnesses arise or do not arise due to conditions.