Mahabharata 12.203.33

मनः सत्त्वगुणं प्राहुः सत्त्वमव्यक्तजं तथासर्वभूतात्मभूतस्थं तस्माद्बुध्येत बुद्धिमान्

manaḥ sattvaguṇaṃ prāhuḥ sattvamavyaktajaṃ tathāsarvabhūtātmabhūtasthaṃ tasmādbudhyeta buddhimān

Our plain-language meaning of this verse is waiting for scholar review.