Yōga Sūtra 4.23

द्रष्टृदृश्योपरक्तं चित्तं सर्वार्थम्।

draṣṭr̥dr̥śyōparaktaṁ cittaṁ sarvārtham।

[द्रष्टृ दृश्या उपरक्तं चित्तं सर्वार्थम्।
draṣṭr̥ = the observer; dr̥śyā = the observed; uparaktaṁ = colored uniformly; cittaṁ = the Chitta; sarvārtham = comprehend all aspects;]

The observer and the observed being colored uniformly, the Chitta can comprehend all aspects.