Mandukya Karika, verse 1.14

Sanskrit text, IAST transliteration and English translation

स्वप्ननिद्रायुतावाद्यौ प्राज्ञस्त्वस्वप्ननिद्रया ।
न निद्रां नैव च स्वप्नं तुर्ये पश्यन्ति निश्चिताः ॥ १४ ॥

svapnanidrāyutāvādyau prājñastvasvapnanidrayā |
na nidrāṃ naiva ca svapnaṃ turye paśyanti niścitāḥ || 14 ||

14. The first two (Viśva and Taijasa) are associated with the conditions of dream and sleeps Prājña is the condition of sleep without dream. Those who have known the truth see neither sleep nor dream in Turīya.

Shankara Bhashya (commentary)

Svapna or dream is the mis-apprehension¹ of Reality like that of the snake in the rope. Nidrā or sleep has already been defined as darkness characterised by the absence of the Knowledge of Reality. Viśva and Taijasa are associated with these, viz., the conditions of dream and sleep. Therefore they have been described as conditioned by the characteristics of cause and effect. But Prājña is associated with sleep alone without dream; therefore it is described as conditioned by cause only. The knower of Brahman does not see them (dream and sleep) in Turīya,² as it would be inconsistent like seeing darkness in the Sun. Therefore³ Turīya has been described as not associated with the conditions of cause and effect.

Anandagiri Tika (glossary)

¹ Mis-apprehension—i.e., when one, then, thinks of Ātman as endowed with body, etc.

² Turīya—Ajñāna and its effects cannot exist in Turīya which is pure Knowledge.

³ Therefore—It is because there is no Nidrā or sleep in Turīya.