The Five Modifications of the Mind — Vrittis
Patanjali identifies five categories of mental modification — correct knowledge, error, imagination, sleep, and memory — both painful and non-painful, that must be understood and stilled.
In sutras 1.6-1.11, Patanjali catalogs the five types of vritti (mental modifications): Pramana (correct knowledge — from direct perception, inference, or scripture), Viparyaya (incorrect knowledge or error), Vikalpa (imagination or verbal delusion without substance), Nidra (sleep, the modification of the void), and Smriti (memory, the retention of experienced objects). Each is further classified as painful (klishta) or non-painful (aklishta). What is remarkable is Patanjali's inclusion of correct knowledge and sleep in this list — even accurate perception is still a modification that creates identification with the content of consciousness rather than consciousness itself. Only when all five vrittis are stilled does pure consciousness shine undisturbed.
They are: correct knowledge, error, imagination, sleep, and memory.
Vyasa's Yoga Bhashya, the oldest commentary on the Yoga Sutras (c. 4th-5th century CE), provides detailed examples of each vritti and explains why even seemingly positive mental states like accurate knowledge constitute vrittis that must ultimately be transcended.
Yoga Sutras of Patanjali
Written about in
- What the Yoga Sutras say about a steady mind
Mental activity is sorted into five kinds: accurate knowledge, error, imagination, sleep and memory. Accurate knowledge is on the list, which tells you Patanjali is not after better thinking but after the stillness underneath thinking.
- What the Yoga Sutras say about doubt
Sutras 1.6-1.11 sort all mental activity into five kinds: correct knowledge, error, imagination, sleep, and memory. Doubt is not one of them, which is the point — it is the state of not yet knowing which of the five you are in. Patanjali counts even correct knowledge as a fluctuation still to be stilled.