俱舍論記 29.92

29.92

「體若是實至便同我說」者，論主出過。我體若是實，破云：汝所執我應與蘊異，有別性故，如色異受等。若與蘊異，便違汝宗我蘊不異。又所執我必應有因，有實體故，猶如色等。若從因生，即是無常。然彼計我非是無常，若是無常即三世攝，彼宗說我必非是三世法藏所收。若言不從因生，汝所執我應是無為，非因生故，猶如虛空。若是無為，便同外道見，又違自宗，五法藏中我非無為，復言我體非是常故。又若是無為，應無有用。既無有用，徒執實有竟何所為？我體若是假，如乳、酪等。便同我說，違汝本宗。

[On the lemma]: "If its entity is real … it would then be identical to what I state."
The author of the treatise points out the faults: If the entity of the self is real, he refutes it by saying: The self posited by you would have to be different from the skandhas, because it would have a distinct nature, just as form is different from feeling and so forth. If it were different from the skandhas, it would contradict your school's tenet that the self and the skandhas are not different. Furthermore, the posited self must necessarily have a cause, because it would be a real entity, just like form and so forth. If it arises from a cause, then it is impermanent. Yet they hold that the self is not impermanent; if it were impermanent, it would be subsumed under the three times, whereas their school states that the self is definitely not subsumed under the categories of dharmas of the three times.
If you say that it does not arise from a cause, the self posited by you would have to be unconditioned (asaṃskṛta), because it does not arise from a cause, just like space. If it were unconditioned, it would then be identical to the views of non-Buddhists; moreover, it would contradict your own school, for among the five categories of knowables, the self is not unconditioned, and you further state that the entity of the self is not eternal. Furthermore, if it were unconditioned, it would have no function. Since it would have no function, what is the point of stubbornly grasping that it is real?
If the entity of the self is conceptual, like milk, curd, and so forth, it would then be identical to what I state, and would contradict your original doctrine.