Visuddhimagga IV-193

Adukkhamasukhanti dukkhābhāvena adukkhaṃ.

「不苦不乐」── 无苦为不苦，

Ñ(IV,193): Which has neither-pain-nor-pleasure: no pain owing to absence of pain;

Notes in Chinese translation: 「不苦不乐」（adukkhamasukha），在《解脱道论》中的解说为：「不苦不乐受者，意不摄受，心不弃舍，此谓不苦不乐受。不苦不乐受者，何相、何味、何起、何处？中间为相，住中为味，除是起，喜灭是处」。

Sukhābhāvena asukhaṃ.

无乐为不乐，

Ñ: no pleasure owing to absence of pleasure (bliss).

Etenettha dukkhasukhapaṭipakkhabhūtaṃ tatiyavedanaṃ dīpeti, na dukkhasukhābhāvamattaṃ.

以此（不苦不乐之语）是表示此中的乐与苦的对治法的第三受，不只是说苦与乐的不存在而已。

Ñ: By this he indicates the third kind of feeling that is in opposition both to pain and to pleasure, not the mere absence of pain and pleasure.

Tatiyavedanā nāma adukkhamasukhā, upekkhātipi vuccati.

第三受即指不苦不乐的舍而言。

Ñ: This third kind of feeling named 'neither-pain-nor-pleasure' is also called 'equanimity'.

Sā iṭṭhāniṭṭhaviparītānubhavanalakkhaṇā, majjhattarasā, avibhūtapaccupaṭṭhānā, sukhadukkhanirodhapadaṭṭhānāti veditabbā.

以反对可意与不可意的经验为相，中立为味（作用），不明显（的态度）为现起（现状），乐的灭为足处（近因）。

Ñ: It has the characteristic of experiencing what is contrary to both the desirable and the undesirable. Its function is neutral. Its manifestation is unevident. Its proximate cause should be understood as the cessation of pleasure (bliss).