[681] "'Bhikkhu, this person has eighteen mental explorations (manopavicāra).' Thus indeed was this said. In dependence on what was this said? Having seen a form with the eye, one explores a form that is a basis for joy, explores a form that is a basis for grief, explores a form that is a basis for equanimity (upekkhā). Having heard a sound with the ear … having smelled an odor with the nose … having tasted a flavor with the tongue … having touched a tangible with the body … having cognized a mind-object (dhamma) with the mind, one explores a mind-object that is a basis for joy, explores a mind-object that is a basis for grief, explores a mind-object that is a basis for equanimity. Thus there are six explorations with joy, six explorations with grief, six explorations with equanimity. 'Bhikkhu, this person has eighteen mental explorations'—when this was said, it was in dependence on this that it was said."
English translation from the Pali (Siam Raṭṭha edition) — under review, not for citation.