Bhagavad Gita: Chapter 2, Verse 16

नासतो विद्यते भावो नाभावो विद्यते सतः ।
उभयोरपि दृष्टोऽन्तस्त्वनयोस्तत्त्वदर्शिभिः ॥ २-१६ ॥

nāsato vidyate bhāvo nābhāvo vidyate sataḥ
ubhayor api dṛṣṭo ’ntas tv anayos tattva-darśibhiḥ 2.16

That which is unreal never exists and that which is real has no non-existence. But the nature of both real and unreal, indeed, has been realized by the seers of Truth.