Valmiki Ramayana Aranya Kanda Sarga 66 Shloka 15
Original Shlokaतत्त्वतो हि नरश्रेष्ठ बुद्ध्या समनुचिन्तय। बुध्द्या युक्ता महाप्राज्ञा विजानन्ति शुभाशुभे।।3.66.15।।
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नरश्रेष्ठ O best among men, तत्त्वतः the facts, बुद्ध्या applying your intellect, समनुचिन्तय think rightly, महाप्राज्ञाः very wise, बुध्द्या with their intellect, युक्ताः endowed, शुभाशुभे right and wrong, विजानन्ति people know.
O best among men judge the facts rightly with your intellect. The wise apply their minds and know what is right and what is wrong.