सर्वार्थान्विपरीतांश्च बुद्धि: सा पार्थ तामसी ॥ ३२ ॥
sarvārthān viparītāṁś ca
buddhiḥ sā pārtha tāmasī
That understanding which considers irreligion to be religion and religion to be irreligion, under the spell of illusion and darkness, and strives always in the wrong direction, O Pārtha, is in the mode of ignorance.
Intelligence in the mode of ignorance is always working the opposite of the way it should. It accepts religions which are not actually religions and rejects actual religion. Men in ignorance understand a great soul to be a common man and accept a common man as a great soul. They think truth to be untruth and accept untruth as truth. In all activities they simply take the wrong path; therefore their intelligence is in the mode of ignorance.