俱舍論疏 15.216

15.216

論「不說心狂至故說為狂」，答也。由前六種惡因，感不平等大，令心狂亂。非心狂亂故即異熟果，故不相違。

The Śāstra says: "It is not said that the insane mind […] therefore it is spoken of as insane"—this is the answer. Due to the aforementioned six kinds of bad causes, an imbalance of the great elements is induced, which causes the mind to become deranged. It is not that the mental derangement itself is the fruit of maturation, so there is no contradiction.