Bhagavad Gita 18.29

Reason and conviction are threefold, according to the quality that is dominant. I will explain them fully and separately, O Arjuna!

बुद्धेर्भेदं धृतेश्चैव गुणतस्त्रिविधं श्रृणु।प्रोच्यमानमशेषेण पृथक्त्वेन धनञ्जय॥

buddherbhedaṃ dhṛteścaiva guṇatastrividhaṃ śrṛṇu|procyamānamaśeṣeṇa pṛthaktvena dhanañjaya||

English translation (above): Shri Purohit Swami (1935), public domain. Sanskrit text via github.com/gita/gita (Unlicense).