Scope of Investigation
The Upanishads are the secret, mystical scriptures that conclude the Vedic canon, written between 800 and 300 BCE. They mark a historical transition from external ritualism to internal contemplation.
Through dialogues between sages and students, they repeatedly declare that the subjective self (Atman) is identical to the universal ground of existence (Brahman).
01
The Mandukya & The Four States
The Mandukya Upanishad deconstructs human identity by analyzing three normal states of experience: waking (Jagrat), dreaming (Svapna), and deep sleep (Susupti).
It points to the fourth (Turiya)—not a state itself, but the changeless consciousness that underlies and observes the other three. This Turiya is the true Self.
02
The Mahavakyas
The Upanishads contain the 'Great Sayings' (Mahavakyas) that summarize non-dual truth:
- 'Tat Tvam Asi' (That Thou Art) in the Chandogya.
- 'Aham Brahmasmi' (I am Brahman) in the Brihadaranyaka.
- 'Ayam Atma Brahma' (This Self is Brahman) in the Mandukya.
- 'Prajnanam Brahma' (Consciousness is Brahman) in the Aitareya.
03
Neti Neti (The Method of Negation)
First formulated in the Brihadaranyaka Upanishad, 'Neti Neti' ('not this, not this') is a key contemplative practice.
By systematically stripping away identification with the physical body, sensory experiences, and mental concepts, the seeker isolates the ultimate Subject that can never be turned into an object.