俱舍論疏 10.134

10.134

「論曰至五所緣故」，釋欲界意近行及緣三界多少。欲界具三受故，具有十八意近行也。具有六境，緣欲界境亦具十八也。欲界意識三受俱能別緣色界四境，故具十二也。以色界中無香、味故，無香、味各三也。欲界三受俱容得緣無色法處，所以有三，以無色界無五境，故闕十五也。

[On the Śāstra's statement:] 'The Śāstra says [up to] because there are five cognitive objects', this explains the mental investigations of the desire realm and how many objects of the three realms they take. Because the desire realm possesses all three feelings, it possesses all eighteen mental investigations. Possessing all six objects, taking the objects of the desire realm as referents likewise possesses all eighteen. Mental consciousness in the desire realm with all three feelings can separately take the four objects of the form realm as referents, hence it possesses twelve; because odors and tastes do not exist in the form realm, the three each of odors and tastes are absent. Mental consciousness in the desire realm with all three feelings can all apprehend the dharma-base of the formless realm, so there are three; because the formless realm lacks the five objects, fifteen are missing.