俱舍論頌疏論本 9.31

9.31

故有輪無初者，明無始也。如是惑、業為因故生，生復為因，起於惑業，從此惑業更復有生，故知有輪旋環無始。

"Therefore, the wheel of existence is without a beginning" explains beginninglessness. In this way, due to affliction and karma as causes, there is birth; birth in turn acts as a cause, giving rise to affliction and karma; from these afflictions and karma there is birth once again. Therefore, one knows that the wheel of existence turns in a cycle without a beginning.