As happens with a few articles on this site, as the understanding evolves I end up editing an article a few times until it becomes a bit messy. This is one such article, now rewritten and updated here.
Earlier this year, I spoke of the Mahavakyas – phrases said to be used to assist an aspirant in the shift into Unity. [Updated] However, they largely describe the relationship of aspects of Unity with Brahman. Brahman does not unfold until late in Unity so it would seem these are more for the completion of Unity and the shift into Brahman.
I am That, Thou art That, All This is That, That alone Is. From a Unity perspective, That is consciousness or Atman. But from Brahman, That is itself. As English, the phrases can have meaning for both but as Sanskrit, the terms favour the second. The Great Sayings are for the Great Awakening of Brahman.
In the prior article, I listed the 4 from Shankara, as mentioned on Wikipedia.
In a discussion with a friend, it became clear this list is actually backwards. As the “I am That” phrase above illustrates, “I” is where it should start. [Update – reversed sequence correctly – see comments]
1. Prajnanam Brahma – “Consciousness is Brahman” or “That alone Is”
(Aitareya Upanishad 3.3 of the Rig Veda)
2. Ayam Atma Brahma – “This Self (Atman) is Brahman”
(Mandukya Upanishad 1.2 of the Atharva Veda)
(also as Sarvum
Kalvidam Kaluhidam Bramha – “All This is That”)
3. Tat Tvam Asi – “Thou art That”
(Chandogya Upanishad 6.8.7 of the Sama Veda)
4. Aham Brahmasmi – “I am Brahman”
(Brhadaranyaka Upanishad 1.4.10 of the Yajur Veda)
Note that they come from each of the 4 primary Vedas. They also map the components of full realization from the higher stages of consciousness.
The 4 related realizations were in the sequence of discovery:
Aham Vishvam: I am the Universe
(Taittiriya Upanishad 3.10)
Devo Hum: I am the Devata
Aham Shrivir: I am the Cosmic Body
Veda Hum: I am the Veda