俱舍論記 20.48

20.48

「此復應詰至去來性不成」者，經部復詰。若去、來世體俱是有，如何可言是去、來性二世差別？故說彼有，據曾有因、據當有果，非體實有。世尊為遮謗因果見，據曾、當義說有去、來，有聲通顯有、無法故。有顯有法，相顯可知，不指事說；有顯無法，相隱難知，故指事云。如世間說：有燈先時無，謂燈未生；有燈後時無，謂燈已滅。又如有言：有燈已滅，非我今滅。此雖說有，皆顯無法。說有去、來，義亦應爾，有顯無法。若不爾者，體皆實有，去、來性不成。

Regarding "This should be questioned again [...] the nature of past and future is not established": The Sautrāntika questions again. If the entities of the past and future times both exist, how can one speak of a difference between the two times as the nature of past and future? Therefore, when their existence is spoken of, it is based on the previously existing cause and based on the effect that will exist, not on real existence of the entity. To prevent the view that slanders cause and effect, the World-Honoured One spoke of the existence of the past and future based on the sense of "previously existed" and "will exist," because the word "existence" applies generally to express both existent and non-existent phenomena. When "existence" expresses an existent phenomenon, its characteristics are manifest and can be known without pointing to an instance; when "existence" expresses a non-existent phenomenon, its characteristics are concealed and difficult to know, so an instance is pointed to, as the worldly say: "there is a lamp that previously did not exist," meaning the lamp had not yet been produced; "there is a lamp that later does not exist," meaning the lamp has already ceased. Or as it is said: "There is a lamp that has already ceased, it is not I who extinguished it now." Although these speak of "existence," they all express non-existent phenomena. Speaking of the existence of past and future should also be understood in this way: "existence" expresses a non-existent phenomenon. If it were not so, the entities would all be real, and the nature of past and future would not be established.