The Equation

A father tells his son to put a lump of salt into a bowl of water and to come back in the morning. The boy does it. The next day the father says, bring me the salt you put in the water last evening. The boy reaches into the bowl and cannot find it. It has dissolved. Taste the water at this edge, the father says. Salt. The middle. Salt. The far edge. Salt. The salt is in all of it and cannot be picked out of any of it.

The lesson the father draws from the bowl is the largest claim the Upanishads make. It is also, read carefully, one of the oldest arguments by experiment in any literature. He has not asserted the conclusion. He has built it from a thing the boy can touch.

This chapter is about that conclusion, and about the four short sentences in which the tradition later fixed it.

Two words

Everything here turns on two Sanskrit words, and the whole of Vedanta is the long argument over the small word that joins them.

The first is atman. It means the self, but not the self of biography, not the bundle of name, memory, and preference you would list if asked who you are. Atman is what remains when those are peeled away, the bare fact of being a conscious subject at all, the one that is awake behind the eyes. The texts hunt for it by removing everything it is not, a method the fifth chapter of this volume takes up under its own name.

The second is brahman. From a root meaning to grow, to swell, to burst forth, it names the absolute: the ground of all being, the reality from which the worlds come and into which they return, the totality. In the older ritual layer the word had pointed at the power in the sacred utterance, the force in the formula. By the time of the Upanishads it has expanded to mean the force behind everything.

The ordinary assumption, the one almost every religious system in history has made, is that the self in here and the absolute out there are two different orders of thing, separated by an unbridgeable distance, and that the religious life is the work of crossing it. The Upanishads make the opposite claim, and they make it flatly. The distance is not there. Atman is brahman. The reality at the centre of the person and the reality at the bottom of the cosmos are one reality, met from two sides.

The four sentences

The later tradition, and specifically the lineage of Advaita Vedanta that traces itself to Shankara, gathered the statement of this identity into four sentences and called them the mahavakyas, the great sayings. One was drawn from each of the four Vedas, and in the initiation of a renunciant in the Dashanami order the four were transmitted as the core of what the new monk was to realize.

It is worth saying at once what this grouping is and what it is not, because the neat scheme has a way of presenting itself as the texts’ own. The Upanishads nowhere line these four up as a set. They nowhere call them “the great sayings.” The one-per-Veda symmetry is a later curation, elegant and useful and not original. What is original is each sentence, sitting inside its own text, doing its own work. Read in place, they are more interesting than the list that flattens them.

The first is the one the salt was for. In the sixth chapter of the Chandogya Upanishad, the sage Uddalaka Aruni instructs his son Shvetaketu, who has come home from twelve years of study swollen with book-learning and short on understanding. Uddalaka takes him through example after example, the salt in the water, the seed of the great banyan that contains a tree it is too small to show, and after each one he repeats a single refrain. In Robert Hume’s public-domain rendering of 1921:

That which is the finest essence, this whole world has that as its soul. That is Reality. That is Atman. That art thou, Shvetaketu.

Tat tvam asi. That thou art. The refrain returns nine times across the chapter, hammered home like a nail given one more strike each time the boy thinks he has understood. It is assigned, in the fourfold scheme, to the Sama Veda, to which the Chandogya belongs.

The second comes from the Brihadaranyaka Upanishad, the great forest text of the White Yajurveda. Here the statement is made of reality itself, at the first moment of its self-knowledge, and not of the student. Hume:

Verily, in the beginning this world was Brahma. It knew only itself: ‘I am Brahma!’ Therefore it became the All.

Aham brahmasmi. I am Brahman. The text adds that whoever knows this in the same way becomes the All in turn. The realization attributed to the cosmos at its origin is the realization offered to the listener now.

The third is the shortest, and the most abstract. From the Aitareya Upanishad, embedded in the Rigvedic schools, comes a single equation after a long meditation on what guides and underlies everything. The line is prajnanam brahma. Hume, who renders prajnana as intelligence rather than the more common consciousness, gives it as “Brahma is intelligence.” Consciousness, intelligence, the awareness that knows: this, the text says, is what brahman is. The cited location is usually given as Aitareya 3.3, sometimes with its section as 3.1.3. The sentence is one; only the numbering varies between editions.

The fourth is assigned to the Atharva Veda, through the smallest of all the principal Upanishads, the Mandukya, a text of twelve verses that the fifth chapter of this volume reads closely. Its second verse states the identity and then opens it for analysis. Hume:

For truly, everything here is Brahma; this self is Brahma.

Ayam atma brahma. This self is Brahman. The same sentence appears independently in the Brihadaranyaka as well, at the close of its honey doctrine, where Müller’s older translation renders the surrounding teaching “this Self is Brahma, the all-perceiving.” That it sits in two Vedas at once is a quiet reminder that the per-Veda assignment is a selection laid over the texts, not a fact discovered in them.

Why four

The number four is doing quiet work in the scheme, and it pays to notice it. There are four Vedas, so four great sayings, one apiece, makes a satisfying architecture. It is the kind of symmetry a teaching tradition reaches for because it is memorable, and memory, as the first volume of this work showed at length, was the whole technology of Vedic transmission. A renunciant could carry four sentences across a lifetime.

But the texts contain more than four statements of the identity, and the tradition knew it. The Chandogya alone offers several. “All this is indeed Brahman,” it says in one place, sarvam khalvidam brahma. “One only, without a second,” ekam evadvitiyam, it says of the reality before the world came to be. The Katha Upanishad has its own compressions of the same truth. None of these made the canonical four, and there is no deep reason why the four chosen were chosen beyond the elegance of the per-Veda fit and the authority of the lineages that fixed them.

This is not a complaint against the tradition. It is a caution for the reader. The four mahavakyas are a genuine and ancient teaching device, and they point at something the texts really say. They are also a frame placed around the texts, after the fact, by people with a particular philosophy to transmit. The frame is Advaita’s. The sentences belong to everyone. Keeping the two apart is the difference between reading the Upanishads and reading a school’s reading of them, and the historian’s job is to keep them apart even while honouring both.

What the sentence will and will not settle

Read the four together and the temptation is to treat the matter as closed. The self is the absolute; the Upanishads said so in four places; the rest is commentary. The history of Vedanta is the proof that it is not closed, and the smallest of the four sentences is where the whole later argument concentrates.

Tat tvam asi. Three words. Tat, that. Tvam, thou. Asi, art. Everything depends on what kind of “art” this is. Shankara read it as the is of strict identity: the self simply is brahman, and the apparent difference between them is ignorance, to be dissolved as the salt dissolved. Later teachers read the same three words differently, as a statement of the closest possible relation in which the self is nevertheless a real part or mode of the divine whole and not collapsed into it. And there is a further wrinkle the historian is obliged to record. The Sanskritist Joel Brereton has argued on grammatical grounds that the phrase in its original context may be less a bald equation than a statement about how the listener exists, something closer to “in that way are you.” The reading is contested. It is named here because honesty requires it, and set down beside the others without a verdict.

This is the posture this whole treatise keeps. Where the texts speak plainly, they are reported plainly. Where the great readers diverge, the divergence is named and the positions are set side by side. The Upanishads give the equation. They do not hand over the interpretation, and the centuries of Vedanta are the record of careful people refusing to agree on it.

What is not in dispute is the audacity of the claim itself, and the fact that it is made without raising its voice. A father with a bowl of salt water. A line repeated to a proud boy until it lands. A cosmos waking to say I am. The grandest assertion in the literature, delivered in the register of instruction.

The next chapter leaves the assertion and goes to the people who forced it into the open, the questioners whose stubbornness the texts preserved: a boy who out-argued Death, a woman who silenced an assembly, a son who would not stop asking his father what happens to the salt.