[255] How is it that wisdom in fathoming the conduct of consciousness in its diversity and unity, through the pervasion of the three kinds of mind (citta) and by way of the clarity (pasāda) of the faculties (indriya), is the knowledge of penetration of the minds of others (cetopariyañāṇa)?
Here a bhikkhu develops the basis of spiritual power (iddhipāda) endowed with concentration (samādhi) due to zeal (chanda) and volitional formations of striving (padhānasaṅkhāra); concentration due to energy …; concentration due to mind …; he develops the basis of spiritual power endowed with concentration due to investigation (vīmaṃsā) and volitional formations of striving. He thoroughly develops the mind in these four bases of spiritual power, thoroughly tames it, makes it malleable and workable. Having thoroughly developed the mind in these four bases of spiritual power, having thoroughly tamed it, made it malleable and workable, he knows thus: "This form (rūpa) has originated from the joy faculty (somanassindriya); this form has originated from the grief faculty (domanassindriya); this form has originated from the equanimity faculty (upekkhindriya)."
With his mind thus developed, purified, and cleansed, he directs and inclines his mind to the knowledge of penetration of the minds of others. Having encompassed with his own mind the mind of other beings, of other persons, he understands: a mind with lust he understands as "a mind with lust"; a mind without lust he understands as "a mind without lust"; a mind with hatred he understands as "a mind with hatred"; a mind without hatred, or a mind with delusion, or a mind without delusion, or a contracted mind, or a distracted mind, or an exalted mind, or an unexalted mind, or a surpassable mind, or an unsurpassable mind, or a concentrated mind, or an unconcentrated mind, or a liberated mind, or an unliberated mind, or a resolved mind, or an unresolved mind—an unresolved mind he understands as "an unresolved mind."
That is knowledge (ñāṇa) in the sense of what is known; it is wisdom in the sense of understanding. Therefore it is said: wisdom in fathoming the conduct of consciousness in its diversity and unity, through the pervasion of the three kinds of mind and by way of the clarity of the faculties, is the knowledge of penetration of the minds of others.
English translation from the Pali (Siam Raṭṭha edition) — under review, not for citation.