MahāvaggavaggaEkaccaṁatthītikathā

Abhidhammapiṭaka · Kathāvatthu · Vol. 37 · Section 424

[424] [P.] Should it not be said, "Future phenomena subject to arising (anāgatā uppādino dhammā) — they exist"? [S.] Yes. [P.] But will not future phenomena subject to arising arise? [S.] Yes. [P.] If future phenomena subject to arising will arise, then indeed, good sir, it should be said, "Future phenomena subject to arising — they exist."

English translation from the Pali (Siam Raṭṭha edition) — under review, not for citation.