Chapter XIII · Śloka 21
कार्यकारणकर्तृत्वे हेतुः प्रकृतिरुच्यते ।
पुरुषः सुखदुःखानां भोक्तृत्वे हेतुरुच्यते ॥
पुरुषः सुखदुःखानां भोक्तृत्वे हेतुरुच्यते ॥
kārya-kāraṇa-kartṛtve hetuḥ prakṛtir ucyate |
puruṣaḥ sukha-duḥkhānāṃ bhoktṛtve hetur ucyate ||
puruṣaḥ sukha-duḥkhānāṃ bhoktṛtve hetur ucyate ||
Prakṛti is said to be the cause with respect to the production of effect and cause; puruṣa is said to be the cause with respect to the experience of pleasure and pain.
The division of labor: prakṛti is the efficient and material cause of all that is created and done, while puruṣa is the locus of experience — it is because of consciousness (puruṣa) that pleasure and pain are actually felt. Agency belongs to nature; sentience belongs to spirit.