When the mind attains that imperturbable peace, then nirvāṇa is reached

The Mumukṣu Prakaraṇa asked about the desire for liberation; the Vairāgya Prakaraṇa explored detachment as a condition. Now Vasiṣṭha introduces the third pillar: upaśama, the radical stillness of the mind. Not the forced stillness of an ascetic who represses, but the naturalness of a flame consuming its own fuel. When the vāsanās exhaust their projective impulse, the mind does not die: it reveals itself as what it always was — a stainless mirror, a cloudless sky. This stillness is not the result of a method but the consequence of having seen the futility of every method aimed at obtaining something. Patañjali, in I.12, called it abhyāsa-vairāgyābhyāṃ tannirodhaḥ: the cessation of vṛttis through practice and detachment. But Vasiṣṭha goes further: stillness does not require active cessation, but the natural exhaustion of what ceases by itself when looked at directly.