गुणत्रयं कारणकार्यकर्तृ ।
येनैव तुर्येण तदेव सत्यम् ॥ २० ॥
samanvayena vyatirekataś ca
yenaiva turyeṇa tad eva satyam
vijñānam — (the mind, whose symptom is) full knowledge; etat — this; tri-avastham — existing in three conditions (wakeful consciousness, sleep and deep sleep); aṅga — My dear Uddhava; guṇa-trayam — manifesting through the three modes of nature; kāraṇa — as the subtle cause (adhyātma); kārya — the gross product (adhibhūta); kartṛ — and the producer (adhidaiva); samanvayena — in each of them, one after another; vyatirekataḥ — as separate; ca — and; yena — by which; eva — indeed; turyeṇa — fourth factor; tat — that; eva — alone; satyam — is the Absolute Truth.
The material mind manifests in three phases of consciousness — wakefulness, sleep and deep sleep — which are products of the three modes of nature. The mind further appears in three different roles — the perceiver, the perceived and the regulator of perception. Thus the mind is manifested variously throughout these threefold designations. But it is the fourth factor, existing separately from all this, that alone constitutes the Absolute Truth.
As stated in Kaṭha Upaniṣad (2.2.15), tam eva bhāntam anubhāti sarvaṁ/ tasya bhāsā sarvam idaṁ vibhāti: “Everything radiates its illumination in pursuance of His original illumination; His light illuminates everything in this universe.” As thus described, the entire range of perception, cognition and sensitivity is an insignificant expansion of the perception, cognition and sensitivity of the Personality of Godhead.