Samkhya Karika 56

इत्येष प्रकृतिकृतौ महदादिविशेषभूतपर्यन्तः ।
प्रतिपुरुषविमोक्षार्थं स्वार्थ इव परार्थ आरम्भः ॥ ५६ ॥

ityeṣa prakṛtikṛtau mahadādiviśeṣabhūtaparyantaḥ ।
pratipuruṣavimokṣārthaṁ svārtha iva parārtha ārambhaḥ ॥ 56 ॥

Ityeṣaḥ=iti+eṣaḥ= this (evolution – what has been described thus far); prakṛti=mūla prakriti; kṛtau=in the creation; mahat=buddhi; ādi=starting from; viśeṣa=specific; bhūta=gross elements; paryantaḥ=up to; prati=each; puruṣa=Purusha; vimokṣa=liberation; arthaṁ=purpose; svārthaḥ=own interest; iva=as if; parārtha=in the interest of another; ārambhaḥ=undertaken

This creation from Mahat (intellect) down to the gross elements is a result of the modifications of Prakriti for the liberation of each Purusha. This is done in the interest of another appearing as if in its own interest.