Patanjali Yoga Sutra 2.4

Ignorance is the field of those that follow — whether dormant, thin, interrupted, or fully out.

अविद्या क्षेत्रमुत्तरेषां प्रसुप्ततनुविच्छिन्नोदाराणाम् ॥

avidya ksetram uttaresam prasupta-tanu-vicchinna-udaranam ||

Ignorance is the field of those that follow — whether dormant, thin, interrupted, or fully out.

Mental struggles move through four distinct states: