俱舍論頌疏論本 1.132

1.132

應知六識轉為意者，明有意界。應知六識轉謝過去，能與後識為所依邊，名為意界。故知六識居現在世名識，在過去名意。

"Should be known as: the six consciousnesses transform into the mind" clarifies the existence of the mind element. It should be known that when the six consciousnesses pass away into the past, insofar as they can serve as the basis for a subsequent consciousness, they are called the mind element. Therefore, one knows that when the six consciousnesses dwell in the present tense they are called consciousness, and when in the past they are called mind.