俱舍論疏 22.103

22.103

論「且以諸樂因至非不決定」，破樂因不定。謂觀所依身分位差別，外境方為樂因。或唯苦因，非唯外境。如所依患冷，煖為樂因；所依患熱，冷為樂因。翻此苦因。苦、樂之因非唯外境，亦依身分為苦、樂因。分位決定，因亦定也。

On the Śāstra's 'First, because causes of pleasure [...] are not indeterminate': This refutes [the view that] causes of pleasure are indeterminate. It means that depending on the difference in the states of the support—the body—an external object only then becomes a cause of pleasure. Or it may be only a cause of suffering; it is not determined by the external object alone. For instance, when the bodily support suffers from cold, warmth is a cause of pleasure; when the bodily support suffers from heat, cold is a cause of pleasure. The reverse applies to causes of suffering. The causes of suffering and pleasure are not solely external objects; they also depend on the body to be causes of suffering or pleasure. Since the state is determinate, the cause is also determinate.