कार्यकारणकर्तृत्वे हेतुः प्रकृतिरुच्यते । पुरुषः सुखदुःखानां भोक्तृत्वे हेतुरुच्यते ॥ १३-२१॥ kāryakāraṇakartṛtve hetuḥ prakṛtirucyate puruṣaḥ sukhaduḥkhānāṃ bhoktṛtve heturucyate In the production of the effect and the cause, PRAKRITI is said to be the cause; in the experience of pleasure and pain, PURUSHA is said to be the cause. kārya = of effect; kāraṇa = and cause; kartṛtve = in the matter of creation; hetuḥ = the instrument; prakṛtiḥ = material nature; ucyate = is said to be; puruṣaḥ = the living entity; sukha = of happiness; duḥkhānāṃ = and distress; bhoktṛtve = in enjoyment; hetuḥ = the instrument; ucyate = is said to be.;