Satyasya Satyam

 By sheer speculation on the meaning of the facts of the external world, the Vedic thinkers had earlier arrived at a unitary conception of the universe, at a materialistic monism, through their concepts of avyakta, indeterminate nature, or prana cosmic energy. But the culminating point of their discoveries was the spiritual unification of all experience in the Atman or Brahman: Brahmaivedam visvamidam varishtham—‘All this manifested universe is verily Brahman the Supreme’ (Mundaka, II. 2. 12); idam sarvarm yadayam atma—‘All this (manifested universe) is this Atman’ (Brhadaranyaka, II. 4. 6); and tat etat brahma apurvam anaparam anantaram abahyam, ayam atma brahma sarvanubhuh —‘This Brahman is without a prior or a posterior, without interior or exterior, this Atman is Brahman, the experiencer of everything’ (ibid., II. 5. 19).