Tikaniddesa

Abhidhammapiṭaka · Dhammasaṅgaṇī · Vol. 34 · Section 588

[588] Which is that form (rūpa) that is internal (ajjhattika), derived (upādā)? The eye base (cakkhāyatana) … the body base (kāyāyatana) — this is that form that is internal, derived. Which is that form that is external (bāhira), derived? The form base (rūpāyatana) … edible nutriment (kabaḷīkāro āhāro) — this is that form that is external, derived. Which is that form that is external, not derived (no-upādā)? The tangible base (phoṭṭhabbāyatana), the water element (āpodhātu) — this is that form that is external, not derived.

English translation from the Pali (Siam Raṭṭha edition) — under review, not for citation.

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