瑜伽論記 8.406

8.406

辨究不究中，景云：舊解，據今一身不發故名究竟，後身還有發義。今解，此據無大乘種姓之人雖遇勝緣相似發心，一退已後畢竟不熏發，退已熏發者，不定姓為遇惡緣故退，由有種姓故能熏發。

In distinguishing definitive and non-definitive, Jing says: The old explanation held that based on not generating it in this single present lifetime, it is called definitive, but in a future lifetime there is still the possibility of generating it. The present explanation holds that this is based on a person who lacks the Mahāyāna gotra; although encountering supreme conditions they generate a mind in semblance, once they regress, they ultimately never perfuse and generate it again. Those who perfuse and generate it again after regressing are persons of indeterminate gotra who regress because of encountering bad conditions; because they possess the gotra, they are able to perfuse and generate it.