成唯識論述記 2.4

2.4

述曰：即總問也。大乘之餘，即小乘也，若言「異識大乘」亦成。色異心故，今言「離識」，簡違宗過。

The Commentary states: This is the general question. What is "other than the Great Vehicle" is the Lesser Vehicle (Hīnayāna). If one said "different from consciousness," it would also apply to the Great Vehicle, because form is different from mind. Now it says "apart from consciousness" to avoid the fault of contradicting one's own doctrine.