Karika 16

कारणमस्त्यव्यक्तं प्रवर्तते त्रिगुणतः समुदयाच्च। परिणामतः सलिलवत् प्रतिप्रतिगुणाश्रयविशेषात् ॥१६॥

The cause exists in the un-manifest, that instigates the combination of three qualities. Varied multiple effects flow with ease, specially sheltered in the qualities.

It is critical to note, unambiguously cause is attributed to the unmanifest 'Purusha' or the individual soul.