In his fantastic book The Method of Early Advaita Vedanta: A Study of Gaudapada, Sankara, Suresvara and Padmapada (2008), Michael Comans discusses perhaps the most basic question concerning the relationship between the One and the many in the thought of Advaita Vedanta.

The puzzle comes, in part, from the nondual position that Brahman is both the efficient cause and the material cause of all manifestation. An efficient cause alone is not hard to explain in traditional Catholic theology: God created creation; accordingly, the transcendent is, and remains, ontologically different from the immanent. Additionally, garden variety material causes are, on their own, also easy to grasp: the material cause of the clay pot is clay; the material cause of the ocean waves is water.

One more wrinkle: Brahman is indivisible and therefore changeless while manifestation is apparently divisible and thus changeable. How, then, can Brahman be both efficient cause and material cause, be both changeless while–somehow–undergoing alteration?

For, writes Comans, “if Brahman is the material cause, then, as in the case of the clay, some sort of alteration of Brahman must nevertheless occur. And if Brahman undergoes any sort of transformation a number of difficulties arise” (p. 193).

Comans goes on to present us with just some of those difficulties:

If Brahman has parts it is conceivable that one part could transform while another part remains unchanged. But if Brahman has parts, Brahman would be a composite entity, and would thereby be subject to disintegration. Moreover we know that Brahman is without parts from the sruti texts [above all, from The Upanishads] that negate attributes, such as: “Partless, actionless, peaceful, faultless, without taint” (SvU 6.19). Therefore Brahman must be without parts. But there is a difficulty here also for if Brahman is without parts Brahman must undergo transformation in its entirety, and that goes against the sruti which repeatedly says that Brahman is without change. Furthermore, if Brahman transform in its entirety into the world it would amount to saying that Brahman as such would cease to exist, for there would be be no Brahman apart from the world, and the sruti teachings that Brahman is to be known would prove meaningless, because the world can be known without any effort on one’s part, merely by looking. Thus the teaching that Brahman is the material cause that transforms is fraught with difficulty. (p. 193)

To summarize:

1. Either Brahman has parts or it does not.

2. If it has parts, then it would be corruptible; but such, so long as Brahman is the Absolute, is impossible.

3. But if Brahman is partless, then transcendence would collapse into immanence with the result that there would be no Absolute as such.

4. Alternatively (and this is not mentioned by Comans), if Brahman is partless, then no manifestation could ever come into being. But it certainly seems as if there is manifestation (about which more below as we come to unreal causation).

So, how can Brahman be said to be the efficient as well as the material cause of manifestation?

Sankara (alt. Shankara) argues, in what will become the position of early Advaita Vedanta, that “Brahman [in actuality] undergoes absolutely no alteration” (p. 194) and thus causation is unreal, transformation of Brahman merely apparent (vivarta).

What is Sankara’s argument for this conclusion? Comans quotes Sankara’s commentary on The Brahma Sutra:

No, because we maintain that this difference of aspects [i.e., one aspect undergoes transformation while another remains unchanged {Comans’ interpolation}] is constructed by Ignorance (avidya).

The Method of Early Advaita Vedanta, p. 195.

Sankara sounds quite Mahayana Buddhist in this respect as he unties the knot. Here, again, is Comans:

The way that Sankara can resolve the [apparent] contradiction that Brahman becomes the world [material cause] and yet somehow undergoes no change in the process [is partless, etc.] is to interpret the sruti as speaking from two levels, from the perspective of absolute reality (paramartha), as well as from the perspective of empirical reality (vyavahara).

Ibid, p. 196.

We need only to add back Sankara’s remark about ignorance to see how all this fits together. From the vantage point of the finite mind, it seems as if Brahman becomes the world and thus undergoes change. This–that is, the stance of conventional reality–is indeed ignorance, for it is not what the Sages report. From the no-vantage vantage point of ultimate reality (i.e., paramartha), there is no independently existing world undergoing change in the first place. Such, so far as it seemed to the apparently existing, apparently separate finite mind, is merely apparent.

In sum, there exists only the One Mind that, like a single membrane, abides in and as Itself even as it vibrates or shimmers forth in apparent forms that are nothing but Itself and even as such apparent forms sink or subside back into the One, Pristine Mind. Indeed, in the absence of the belief in and stance of the finite mind, it cannot even be said that there is the One Mind, or the many, or the One and the many, or silence or sound, or stillness or pulsation, or nonduality or duality.

This is the doctrine of unreal causation.