Lecture Notes on the Sūtra of the Collection of the Father and Son (IX)

Eighteen Mental Scrutinies

Original text: 云何十八意所伺察。谓眼见色已。若生适悦。若生忧恼。若住于舍。如是六根。各各缘彼。适悦等三。是名十八意所伺察。

Explanation: Scrutinizing means observing, discerning, knowing, and experiencing. For example, after the eye faculty contacts form dust (visual objects), the eye consciousness and the mind consciousness discern the form dust; if a state of mind of joy or of sorrow and vexation arises, or if it abides in a neutral state of feeling that is neither joyful nor sorrowful, then three kinds of feeling appear—this is one faculty paired with three realms. The other five faculties—ear, nose, tongue, body, and mind—are the same as the eye faculty: the faculty contacts the sense object, consciousness arises, and the conscious mind then experiences feelings, producing three types of mental states: either joy, or sorrow and vexation, or neither joy nor aversion (equanimity). These respectively constitute five pairs, fifteen realms; combined together, they make six pairs, eighteen realms. After each faculty contacts its sense object, there are the three realms of faculty, object, and consciousness; the six faculties contacting the six sense objects together constitute the eighteen realms (dhātus), which respectively give rise to the three kinds of feeling—suffering, pleasure, and neutrality. These are the eighteen mental scrutinies.