kārya-kāraṇa-kartṛtve hetuḥ prakṛtir ucyate puruṣaḥ sukha-duḥkhānāṁ bhoktṛtve hetur ucyate
"Nature is said to be the cause of effects, instruments, and agency; the spirit is said to be the cause of the experience of pleasure and pain."
What This Means:
Prakriti (nature) is responsible for all action—the body-mind doing things, the instruments used, the effects produced. Purusha (spirit) is responsible for experiencing pleasure and pain—but not for causing them.
Going Deeper:
Division of roles: Prakṛti causes kārya (effects), kāraṇa (instruments—body, senses), and kartṛtva (sense of doership). Puruṣa causes bhoktṛtva (experiencership) of sukha-duḥkha (pleasure-pain). The confusion (ignorance) is thinking 'I do' when actually prakṛti does, and 'I enjoy/suffer' when purusha merely witnesses. Liberation is seeing this clearly.
How To Apply This:
When you feel 'I am doing this' or 'I am suffering this,' investigate: who is the 'I'? The doing is prakṛti's nature. The pure witnessing is purusha. Can you find the witness who observes both action and experience?
Key Sanskrit Terms: