Bhagavad Gita 18.32

अधर्मं धर्ममिति या मन्यते तमसाऽऽवृता।सर्वार्थान्विपरीतांश्च बुद्धिः सा पार्थ तामसी॥

adharmaṃ dharmamiti yā manyate tamasā''vṛtā |sarvārthānviparītāṃśca buddhiḥ sā pārtha tāmasī ||

That intellect, O Arjuna, which is enveloped in darkness and sees Adharma as Dharma and all things perverted, is Tamasic (dark).

And that which, shrouded in Ignorance, thinks wrong to be right, and sees everything perversely, O Arjuna, that intellect is ruled by Darkness.

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