An Analysis (of the Feeling Faculties) (3)
Vibhaṅga Sutta  (SN 48:38)

“Monks, there are these five faculties. Which five? The pleasure-faculty, the pain-faculty, the happiness-faculty, the distress-faculty, the equanimity-faculty.

“And what is the pleasure-faculty? Any physical pleasure, physical comfort born of body-contact to be experienced as pleasure & comfort. That is called the pleasure-faculty.

“And what is the pain-faculty? Any physical pain, physical discomfort born of body-contact to be experienced as pain & discomfort. That is called the pain-faculty.

“And what is the happiness-faculty? Any mental pleasure, mental comfort born of intellect-contact to be experienced as pleasure & comfort. That is called the happiness -faculty.

“And what is the distress-faculty? Any mental pain, mental discomfort born of intellect-contact to be experienced as pain & discomfort. That is called the distress-faculty.

“And what is the equanimity-faculty? Anything, physical or mental, to be experienced as neither comfort nor discomfort. That is called the equanimity-faculty.

“With regard to this, the pleasure-faculty & happiness-faculty are to be seen as a feeling of pleasure. The pain-faculty & distress-faculty are to be seen as a feeling of pain. The equanimity-faculty is to be seen as a feeling of neither pleasure nor pain. Thus, by this exposition, the five are three; and the three, five.”

See also: MN 59: SN 36:22