*Om* (also written *Aum* or *ॐ*) is the most universally recognised Hindu symbol and the most often-recited syllable. The *Mandukya Upanishad* — one of the shortest and most concentrated of the principal Upanishads — is dedicated entirely to its analysis. Here is what classical Hindu thought says about Om.
✦ The Three Sounds
Spoken slowly and clearly, Om unfolds into three sequential sounds:
- ✦**A** — formed at the back of the throat, with the mouth open. The sound of beginning.
- ✦**U** — formed in the middle of the mouth, with the lips rounding. The sound of progression and continuation.
- ✦**M** — formed at the lips, with the mouth closed. The sound of completion.
So *A-U-M* covers the entire range of vocal articulation — from the open back of the throat to the closed lips. It is, in this sense, a complete sound: it begins where speech begins and ends where speech ends.
✦ The Three Sounds and the Three States
The Mandukya Upanishad maps the three sounds to three classical states of consciousness:
- ✦**A** — *jagrat* (waking consciousness)
- ✦**U** — *svapna* (dream consciousness)
- ✦**M** — *sushupti* (deep dreamless sleep)
Together, the three sounds cover the full range of ordinary experience.
✦ The Fourth — Silence
The Upanishad then makes its central move: *after the M sound dies away, there is silence.* That silence is the fourth — *turiya*, the witness-consciousness that underlies waking, dreaming and deep sleep without itself being any of them. The actual content of Om, in classical Hindu meditative practice, is not the spoken sound but the silence into which the sound dissolves.
This is why advanced practice often involves holding the silence after Om for as long as the sound itself was held. The sound is the door; the silence is what the door opens onto.
✦ The Written Symbol — ॐ
The Devanagari symbol ॐ has its own articulated geometry:
- ✦The lower curve represents *jagrat* (waking)
- ✦The middle curve represents *svapna* (dream)
- ✦The upper curve (extending leftward) represents *sushupti* (deep sleep)
- ✦The crescent and dot above represent *turiya* and the *paramartha* (the absolute), beyond the three states.
The Tamil and Sanskrit calligraphic traditions both treat the symbol with care; it is one of the few Hindu visual elements whose form is inherently meaningful, not just decoratively conventional.
✦ In Scripture
The *Katha Upanishad* (1.2.15-16): *"The goal which all the Vedas declare, that all austerities aim at, that for which men live as students of the holy life, that I will tell you in brief: it is OM."*
The *Bhagavad Gita* (8.13): *"He who departs from the body uttering the single syllable OM, attains the highest goal."*
These are not occasional mentions; they are direct designations of Om as the sound that points most exactly at what the entire Vedic tradition is pointing toward.
✦ In Practice
The simplest practice with Om:
- 1Sit straight, eyes closed.
- 2Take a slow inhalation.
- 3On the exhalation, vocalise *A* slowly, then transition to *U*, then close to *M*. Let the M-hum continue until breath nearly runs out.
- 4Hold a moment of silence at the end of breath before inhaling again.
- 5Repeat 7, 11 or 21 times.
The practice settles the mind quickly. It is one of the few mantra-practices that can be honestly recommended to anyone, of any tradition or none, on the basis of demonstrable physiological effect alone — the long, controlled exhalation produces parasympathetic activation reliably.
✦ Why Om is Universal
In Buddhist mantras (*Om Mani Padme Hum*), Sikh scripture (*Ek Onkar*), Jain texts (*Om* as the namokar's seed), and even Vedic Hindu mantras across all sampradayas — Om appears. It belongs to no single school. The *Mandukya* makes the case that Om is what every spiritual practice is in fact pointing toward; the various traditions are routes to the same underlying recognition.