俱舍論記 9.140

9.140

「已顯老死至此言何用」者，若名色生六處，六處生觸，觸生受，已顯老死為事因。若受生愛，已顯老死為惑因。若受生愛，顯無明為事果。若愛生取，已顯無明為惑果，以過去無明則現屬愛、取二惑性故。未來老死，則現名色、六處、觸、受四事性故。由此已顯老死為因、無明為果，豈假更立餘緣起支？故無終始過也。故契經中說十二緣起云「如是純大苦蘊集」，引經意證無明亦果，老死亦因。十二有支皆通苦、集，諸支果義名為苦蘊，諸支因義說名為集。若不許無明是果、老死是因，此經言何用？

Regarding "It has already manifested that old age and death [...] what would be the use of these words?": If name-and-form produces the six sense-bases, the six sense-bases produce contact, and contact produces feeling, it has already been manifested that old age and death serve as the cause of entities. If feeling produces craving, it has already been manifested that old age and death serve as the cause of afflictions. If feeling produces craving, it manifests ignorance as the fruit of entities. If craving produces grasping, it has already been manifested that ignorance is the fruit of afflictions, because past ignorance belongs in its nature to the two present afflictions of craving and grasping, and future old age and death belong in their nature to the four present entities of name-and-form, the six sense-bases, contact, and feeling. By this, it has already been manifested that old age and death are causes and ignorance is a fruit; why should it rely on further establishing other links of dependent origination? Therefore, there is no fault of an end and a beginning. Hence, in the sūtra it is said of the twelvefold dependent origination: "Thus is the arising of this entire great mass of suffering." Citing this sūtra's intent proves that ignorance is also a fruit, and old age and death are also causes. The twelve links of existence all pertain to suffering and origin: the meaning of the various links as fruits is called the mass of suffering, and the meaning of the various links as causes is said to be the origin. If one does not accept that ignorance is a fruit and old age and death are causes, what would be the use of these words of the sūtra?