Bhagavad Gītā Chapter 13, Verse 20: Krishna to Arjuna — Kṣetra-Kṣetrajña-Vibhāga-Yoga
*Prakṛti* is the cause of the body, the senses, and the capacity for action; *puruṣa* is the cause of the experiencing of pleasure and pain.
Bhāṣyakāra purports
- Śaṅkaraadvaita
Prakrti (primal matter) and purusa (pure witness) are both without beginning — they are the two powers of Isvara without which lordship itself would be impossible. Prakrti, the tri-guna (three-stranded) maya-sakti, is the cause of all vikara (transformation) — body, senses, and their objects; purusa, the unchanging witness, is the cause of bhoga (experience) of sukha-duhkha (pleasure-pain), not as a real enjoyer but as the apparent locus of experience superimposed by avidya (nescience). Both are real as vyavaharika (conventional-empirical) categories, but at the paramarthika (ultimate) level only the non-dual Brahman is; the samsara-cycle that binds is itself beginningless and is dissolved only by jnana (liberating knowledge).
- Rāmānujaviśiṣṭādvaita
The body (karya) and the cognitive-action senses (karana) act because prakrti — the mode of matter that is Bhagavan's body — is their efficient cause when animated by the purusa who dwells within as adhishthatr (indwelling controller). The purusa's kartrtva (agency) is real but derivative: it is the capacity to initiate effort for body-dwelling, dependent on Isvara's sustaining will as established in Brahmasutras 2.3.33. When prakrti-samsrsta (entangled with matter) the purusa becomes the asraya (substrate) of sukha-duhkha-anubhava (experience of joy and pain) — not because pain is intrinsic to him, but because mixed-mode contact with the three gunas produces it; liberation is the purusa returning to sva-anubhava-eka-sukha (joy of self-awareness alone) in Bhagavan's presence.
- Madhvadvaita
Prakrti with its vikara (modifications) — the guna-triad of sattva, rajas, and tamas — is the instrumental cause of all karya (effects in the body-world); these vikara are enumerated separately from the gunas because even a small difference from the state of laya (dissolution) constitutes sarga (manifestation), as the Madhucchandasa-sakha (Madhucchandas branch of sruti) attests. Purusa — the jiva, eternally distinct from both prakrti and from Hari — is the bhoktr (experiencer) of sukha-duhkha, and this bhoktrva belongs to him only in the mode of paratantrya (absolute dependence on Hari). Neither prakrti nor jiva acts or experiences from autonomous selfhood; all movement is Hari's superintendence.
- Vallabhaśuddhādvaita
Prakrti and purusa here are not the inert Sankhya dyad but Bhagavan's own svarupa-saktis — maya-sakti (the unmanifest causal power) and its amsa-jivas (partial expressions) — both anadi (beginningless) because they are non-different from the one Anadi Purusottama. Bhagavata 3.26.4-5 is the key: Bhagavan yad-rcchaya (by sovereign will, not compulsion) entered the suksma-daivi-guna-mayi (subtle, divine, attribute-woven) prakrti as lila (divine play), beheld her and was enchanted — this 'enchantment' is itself lila, not bondage. For the jiva-purusa, vikara (iccha-dvesa-adi, desire-aversion, etc.) become bandha-hetu (cause of binding) when prakrti's avidya-aspect is operative, but those same vikara become amrta-hetu (cause of liberation) when Bhagavan's vidya-aspect, mediated by amanitvadi (humility and the virtues of 13.8-12), illumines the field.
- Śrīdharabhakti
Prakrti and purusa are both anadi (without beginning): were they to have a beginning, an infinite regress of prior causes would follow — therefore the Paramesvara's saktis must be eternal, as Sankarabhasya itself extensively establishes (Sridhara defers to that demonstration). Vikara (modifications of prakrti — body, senses) and guna-parinamana (transformations of the gunas into sukha-duhkha-moha) are all prakrti-sambhava (arising from prakrti alone); the purusa is their bhoktr-hetu (cause of the experiencing) because he is entangled. This samsara-hetu (samsara-causation) framing of the verse fulfils the prior pledge at 13.3-4 to explain 'what the field is, whence it arises, and who knows it' — all resolved in two verses.
- Madhusūdanaadvaita-bhakti
Bhagavan's two praksrtis from BG 7 — the apara-prakrti (lower, the kshetra) and para-prakrti (higher, the jiva) — reappear here: the kshetra-laksana tri-guna maya-sakti is the cause of all vikara (the sixteen: five mahabhuta, eleven indriya) and guna-parinamana (sattva-rajas-tamas, which yield sukha-duhkha-moha); the jiva-purusa is the cause of bhoga because his dharma-adharma-kama drives rebirth and suffering — without this the twin fallacies of krtahani (good deeds going unrewarded) and akrtabhyagama (suffering without prior karma) would follow. Both are anadi: to posit a beginning for either generates anava-stha (infinite regress). Jnana dissolves the superimposition, and bhakti (love of Krsna) is the living texture of that dissolution.