俱舍論記 22.73

22.73

「云何知然」者，問。「且應反徵至有樂應成」者，略作三番徵責經部，顯有實樂。

As for "How is this known to be so?": this is a question. As for "First, one should counter-interrogate... it should be established that pleasure exists": this briefly makes three rounds of interrogation against the Sautrāntikas, demonstrating that there is real pleasure.