Om and Brahman. It's not a metaphor, it's not an exaggeration, it's not poetic license. The Māṇḍūkya Upaniṣad opens with this direct declaration: oṃkāra eva idaṃ sarvam — "Om is all of this that exists."
This is the shortest of the principal Upaniṣads — just 12 mantras. But what it accomplishes in these 12 mantras is extraordinary: it dismantles the entire human experience, shows you that you are already free, and uses Om as the vehicle for this revelation.
Why Om?
Most people know Om as a sound chanted at the beginning of yoga or meditation practices. Some know it's considered "sacred." Few understand why.
Om is not an arbitrary sound chosen by tradition. It is the sound that, according to the Vedas, contains all other sounds. When you open your mouth and produce sound without articulation, you start with "A" (open throat) and end with "M" (closed mouth). "U" is the transition between the two. Every possible sound fits between A and M.
This makes Om the sonic symbol of totality. And that's why the Māṇḍūkya uses it as a means of knowledge.
A-U-M: The Three States of Consciousness
The Māṇḍūkya maps each letter of Om to a state of experience:
A — Waking (Vaiśvānara)
The waking state. You perceive the external world through your senses. There's a "self" that experiences objects out there. It's the most familiar state, and what most people consider "reality."
U — Dreaming (Taijasa)
The dream state. The mind creates an entire world — with objects, people, emotions — without any external input. The dream "self" experiences this world as completely real. Only upon waking do you realize it was a mental projection.
M — Deep Sleep (Prājña)
The dreamless state. There are no objects, no world, no subject-object division. There is only non-dual consciousness and a kind of diffuse well-being. You are aware of nothing — but you are there. The proof? You wake up and say "I slept well" or "I didn't sleep well."
The Silence After Om: Turīya
Here's the deepest point. Beyond the three letters, there is the silence that follows the sound of Om. This silence is called turīya — literally, "the fourth."
Turīya is not a fourth state that you experience beyond the other three. It is the consciousness that is present in all three and does not depend on any of them. It's like the movie screen — the films change (waking, dreaming, deep sleep), but the screen remains.
You don't need to "achieve" turīya. You already are turīya. The confusion (avidyā) is identifying with the content of the states instead of recognizing the consciousness that witnesses them.
Om as a Means of Knowledge (Pramāṇa)
This is a point many people miss. Om is not a mantra to "raise your vibration" or "open chakras." In the Māṇḍūkya, Om functions as pramāṇa — a valid means of knowledge.
When you understand that: - A = waking = the world you experience when awake - U = dreaming = the world the mind projects - M = deep sleep = objectless consciousness - Silence = turīya = you, the consciousness that permeates everything
...you are using Om to know yourself. It's not faith. It's not mystical experience. It's methodical investigation into the nature of reality using a symbol that contains totality.
This is the method of Vedānta: using words (and in this case, a sound) as instruments that point to what you already are.
Om: The Sannyāsī's Mantra
Traditionally, Om is the mantra of the renunciant (sannyāsī). When a person takes sannyāsa — the formal order of renunciation — the mantra they receive is Om.
Why? Because Om represents totality. The sannyāsī is one who has recognized (or is on the path to recognizing) that there is nothing outside of themselves to seek. If Om is everything, and if you are Om, what is left to conquer?
The sannyāsī doesn't renounce the world because the world is bad. They renounce the search — the search for completeness in objects, situations, relationships. And Om, as the symbol of totality, is the constant reminder of this truth.
This doesn't mean Om is exclusive to sannyāsīs. Anyone can and should chant Om. But understanding that Om is the mantra of renunciation helps to grasp the depth of what this sound represents.
The Māṇḍūkya in Practice
How can you use this knowledge?
- When chanting Om, do so with understanding. When you pronounce A, contemplate the waking state and all that you experience when awake. With U, contemplate the dream world and the creative power of the mind. With M, contemplate deep sleep and objectless consciousness. In the silence, recognize yourself — the consciousness that is present in all three states.
2. In [meditation](/blog/meditacao-vedanta-diferenca), use Om as an object of contemplation. Not as mechanical repetition, but as an investigation: who am I that perceives waking, dreaming, and deep sleep? Who am I that remains while the states come and go?
3. In study, the Māṇḍūkya with the Kārikā of Gauḍapāda (a verse commentary) is one of the most important texts of Vedānta. If you are in a gurukulam or studying with a qualified teacher, this text will be studied at some point.
Summary
The Māṇḍūkya Upaniṣad doesn't teach you to chant Om. It teaches you to understand Om. And by understanding Om, you understand yourself — because Om is you, and you are Brahman.
It's not mysticism. It's the most direct method the Vedic tradition offers for self-knowledge.
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