Bhagavad Gita Chapter 3, Verse 28

तत्त्ववित्तु महाबाहो गुणकर्मविभागयोः | गुणा गुणेषु वर्तन्त इति मत्वा न सज्जते ||

tattva-vit tu mahā-bāho guṇa-karma-vibhāgayoḥ guṇā guṇeṣu vartanta iti matvā na sajjate

But the knower of truth, O mighty-armed Arjuna, understanding the categories of gunas and actions, and knowing 'gunas act upon gunas,' does not become attached.

After showing how the deluded think 'I am the doer,' Krishna now reveals the wise perspective. The tattva-vit (knower of truth) understands that gunas act upon gunas—nature interacts with nature. Your senses are gunas, sense objects are gunas. When you're angry, that's guna (brain chemistry) reacting to guna (words, situation). When you're happy, guna (nervous system) responding to guna (pleasant circumstance). There's no personal 'I' doing anything—just prakṛti acting on prakṛti. Seeing this creates na sajjate (non-attachment)—not because you suppress feelings, but because you see there's no personal 'me' to be attacked, rejected, or judged.