Mahat-tattva, or the great causal truth, transforms into false ego, which is manifested in three phases — cause, effect and the doer. All such activities are on the mental plane and are based on the material elements, gross senses and mental speculation. The false ego is represented in three different modes — goodness, passion and ignorance.
Srimad Bhagavata Purana
श्रीमद्भागवतमहापुराणम्
मूल श्लोकः
महत्तत्त्वाद्विकुर्वाणादहन्तत्त्वं व्यजायत । कार्यकारणकर्त्रात्मा भूतेन्द्रियमनोमयः
mahattattvādvikurvāṇādahantattvaṃ vyajāyata | kāryakāraṇakartrātmā bhūtendriyamanomayaḥ
SB 3.5.29