Here is something important. Sri Aurobindo says that everything is involved down here - the mind, the vital, the supermind - and that what is involved evolves. But if everything is involved, including the supermind, what is the need for a 'descent'? Can't things evolve by themselves?
Ah! He has explained this somewhere.
But I don't remember seeing anything that satisfied me.
Isn't it in the Essays on the Gita ? He explains what Krishna says and how the two [descent and evolution] are combined. I read it not long ago because I was interested in this very question. And I even said something myself about the difference between what evolves (what emerges from this involution) and the Response from what already exists above in all its glory.
We'll have to find this passage.
There are two lines in the ancient traditions, two ways of explaining this. One says it is by the 'descent' of what already exists in all its perfection that what is involved can be awakened to consciousness and evolution. It's like the old story: when what Sri Aurobindo calls the universal Mother or the Shakti (or Sachchidananda [[Sachchidananda is the Supreme Consciousness in its triple aspect of Existence (Sat), Consciousness (Chit) and Bliss (Ananda). ]] ) realized what had happened in Matter (that is, in what had created Matter) and that this involution had led to a state of Inconscience, total unconsciousness, the ancient lore says that at once the divine Love descended straight from the Lord into Matter and began to awaken what was involved there. 
Other traditions speak of the Consciousness, the divine Consciousness, instead of Love. One even finds accounts full of imagery depicting a Being of prismatic light lying in deep sleep in the cave of the Inconscient; and this Descent awakens him to an activity which is still (how to put it?) inner, an immobile activity, an activity by radiation. Countless rays issue from his body and spread throughout the Inconscient, and little by little they awaken in each thing, in each atom, as it were, the aspiration to Consciousness and the beginning of evolution.
I have had this experience.
I have had the experience of being 'missioned,' so to speak, in a form of Love and Consciousness combined - divine Love in its supreme purity, divine Consciousness in its supreme purity - and emanated DIRECTLY, without passing through all the intermediate states, directly into the nethermost depths of the Inconscient. And there I had the impression of being, or rather of finding a symbolic Being in deep sleep ... so veiled that he was almost invisible. Then, at my contact, the veil seemed to be rent and, without his awakening, there was a sort of radiation spreading out.... I can still see my vision. [[See the addendum following this conversation for a transcription of Mother's vision as she noted it down for publication in Theon's Cosmic Review in 1906. ]]
There is always what could almost be called a popular way of presenting things. Take the whole Story of the Creation, of how things have come about: it can be told as an unfolding story (this is what Theon did in a book he called The Tradition - he told the whole story in the Biblical manner, with psychological knowledge hidden in symbols and forms). There is a psychological manner of telling things and a metaphysical manner. The metaphysical, for me, is almost incomprehensible; it's uninteresting (or interesting only to minds that are made that way). An almost childish, illustrative way of telling things seems more evocative to me than any metaphysical theory (but this is a personal opinion - and of no great moment!). The psychological approach is more dynamic for transformation, and Sri Aurobindo usually adopted it. He doesn't tell us stories (I was the one who told him stories! Images are very evocative for me).  But if one combines the two approaches.... Actually, to be philosophical, one would have to combine the three. But I have always found the metaphysical approach ineffective; it doesn't lead to realization but only gives people the IDEA that they know, when they really know nothing at all. From the standpoint of push, of a dynamic urge towards transformation, the psychological approach is obviously the most powerful. But the other [the symbolic approach] is lovelier!
In The Hour of God, there's a whole diagram of the Manifestation made by Sri Aurobindo [[Cent. Ed., Vol. XVII, p. 28 ff. ]] : first comes this, then comes that, then comes the other, and so forth - a whole sequence. They published this in the book in all seriousness, but I must say that Sri Aurobindo did it for fun (I saw him do it). Someone had spoken to him about different religions, different philosophical methods - Theosophy, Madame Blavatski, all those people (there was Theon, too). Well, each one had made his diagram. So Sri Aurobindo said, 'I can make a diagram, too, and mine will be much more complete!' When he finished it, he laughed and said, 'But it's only a diagram, it's just for fun.' They published it very solemnly, as if he had made a very serious proclamation. Oh, it's a very complicated diagram!
But the trouble is that people will say: what's the need for a 'descent' if all is involved and then evolves? Why a descent? Why should there be an intervention from a higher plane?
I beg your pardon, but what was built up through this involution had to be unbuilt. The CAUSE of this involution had to be undone.
The way Theon told it, there was first the universal Mother (he didn't call her the universal Mother, but Sri Aurobindo used that name), the universal Mother in charge of creation. For creating she made four emanations: Consciousness or Light; Life; Love or Beatitude and (Mother tries in vain to remember the fourth) ... I must have cerebral anemia today! In India they speak only of three: Sat-Chit-Ananda (Sat is Existence, expressed by Life; Chit is Consciousness, expressed by Power; Ananda is Bliss, synonymous with Love). But according to Theon, there were four (I knew them by heart). Well, these emanations (Theon narrated it in such a way that someone not a philosopher, someone with a childlike mind, could understand), these emanations, conscious of their own power, separated themselves from their Origin; that is, instead of being entirely surrendered to the supreme Will and expressing only....  Ah, the fourth emanation is Truth! Instead of carrying out only the supreme Will, they seem to have acquired a sense of personal power. (They were personalities of sorts, universal personalities, each representing a mode of being.) Instead of remaining connected, they cut the link - each acted on his own, to put it simply. Then, naturally, Light became darkness, Life became death, Bliss became suffering and Truth became falsehood. And these are the four great Asuras: the Asura of Inconscience, the Asura of Falsehood, the Asura of Suffering and the Asura of Death.
Once this had occurred, the divine Consciousness turned towards the Supreme and said (Mother laughs): 'Well, here's what has happened. What's to be done?' Then from the Divine came an emanation of Love (in the first emanation it wasn't Love, it was Ananda, Bliss, the Delight of being which became Suffering), and from the Supreme came Love; and Love descended into this domain of Inconscience, the result of the creation of the first emanation, Consciousness - Consciousness and Light had become Inconscience and Darkness. Love descended straight from the Supreme into this Inconscience; the Supreme, that is, created a new emanation, which didn't pass through the intermediate worlds (because, according to the story, the universal Mother first created all the gods who, when they descended, remained in contact with the Supreme and created all the intermediate worlds to counterbalance this fall - it's the old story of the 'Fall,' this fall into the Inconscient. But that wasn't enough). Simultaneously with the creation of the gods, then, came this direct Descent of Love into Matter, without passing through all the intermediate worlds. That's the story of the first Descent. But you're speaking of the descent heralded by Sri Aurobindo, the Supramental Descent, aren't you?
Not only that. For example, Sri Aurobindo says that when Life appeared there was a pressure from below, from evolution, to make Life emerge from Matter, and simultaneously a descent of Life from its own plane. Then, when Mind emerged out of Life, the same thing from above happened again. Why this intervention from above each time? Why don't things emerge normally, one after another, without needing a 'descent'?
You may as well ask why everything has gone wrong! No, with experience it becomes easy to understand. 
Take the experience of Mind, for example: Mind, in the evolution of Nature, gradually emerging from its involution; well - and this is a very concrete experience - these initial 'mentalized forms,' if we can call them that, were necessarily incomplete and imperfect, because Nature's evolution is slow and hesitant and complicated. Thus these forms inevitably had an aspiration towards a sort of perfection and a truly perfect mental state, and this aspiration brought the descent of already fully conscious beings from the mental world who united with terrestrial forms - this is a very, very concrete experience. What emerges from the Inconscient in this way is an almost impersonal possibility (yes, an impersonal possibility, and perhaps not altogether universal, since it's connected with the history of the earth); but anyway it's a general possibility, not personal. And the Response from above is what makes it concrete, so to speak, bringing in a sort of perfection of the state and an individual mastery of the new creation. These beings in corresponding worlds (like the gods of the overmind, [[ In Sri Aurobindo's terminology, the 'Overmind' represents the highest level of the mind, the world of the gods and origin of all the revelations and highest artistic creations - the world that has ruled mental man till now. in his gradations of the worlds, Sri Aurobindo speaks of two hemispheres, the upper hemisphere and the lower. The Overmind is the line between these two hemispheres, 'This line is the intermediary overmind which, though luminous itself, keeps from us the full indivisible supramental Light, but in receiving it divides, distributes, breaks up into separated aspects, powers, multiplicities of all kinds.' In the words of the Upanishad, 'The face of the Truth is covered by a golden lid.' ]] or the beings of higher regions) came upon earth as soon as the corresponding element began to evolve out of its involution. This accelerates the action, first of all, but also makes it more perfect - more perfect, more powerful, more conscious. It gives a sort of sanction to the realization. Sri Aurobindo writes of this in Savitri - Savitri lives always on earth, with the soul of the earth, to make the whole earth progress as quickly as possible. Well, when the time comes and things on earth are ready, then the divine Mother incarnates with her full power - when things are ready. Then will come the perfection of the realization. A splendor of creation exceeding all logic! It brings in a fullness and a power completely beyond the petty shallow logic of human mentality.
People can't understand! To put oneself at the level of the general public may be all very well [[Mother is referring to the book Satprem will write on Sri Aurobindo, which prompted the questions posed in this conversation. ]] (personally I have never found it so, although it's probably inevitable), but to hope that they will ever understand the splendor of the Thing.... They have to live it first! 
I myself would NEVER try to deal with the 'why'; I would always say 'this is how it is.' When people ask me, 'Why did it happen like this? Why is the world so unhappy? Why does it have to be dark before growing luminous? Why has there been this "accident" (if it can be called an "accident")? Why did the Lord permit You can say it's because of this, because of that - there are fifty thousand replies and they're all worthless.
It's like this because that's the way it is!
It wasn't so much a question of the 'why' as of the process.
The process? I am giving you an historical process that I know through experience.
Both are needed.
Yes. The earth is a representative and symbolic world, a kind of crystallization and concentration of the evolutionary labor giving it a ... more concrete reality. It has to be taken like this: the history of the earth is a symbolic history. And it is on earth that this Descent takes place (it's not the history of the universal but of the terrestrial creation); the Descent occurs in the individual TERRESTRIAL being, in the individual terrestrial atmosphere.
Let's take Savitri, which is very explicit on this: the universal Mother is universally present and at work in the universe, but the earth is where concrete form is given to all the work to be done to bring evolution to its perfection, its goal. Well, at first there's a sort of emanation representative of the universal Mother, which is always on earth to help it prepare itself; then, when the preparation is complete, the universal Mother herself will descend upon earth to finish her work. And this She does with Satyavan - Satyavan is the soul of the earth. She lives in close union with the soul of the earth and together they do the work; She has chosen the soul of the earth for her work, saying, 'HERE is where I will do my work.' Elsewhere (Mother indicates regions of higher Consciousness), it's enough just to BE and things Simply ARE. Here on earth you have to work.
There are clearly universal repercussions and effects, of course, but the thing is WORKED OUT here, the place of work is HERE. So instead of living beatifically in Her universal state and beyond, in the extra-universal eternity outside of time, She says, 'No, I am going to do my work HERE, I choose to work HERE.' The Supreme then tells her, 'What you have expressed is My Will.'.... 'I want to work HERE, and when all is ready, when the earth is ready, when humanity is ready (even if no one is aware of it), when the Great Moment comes, well ... I will descend to finish my work.' 
That's the story.
So if people ask 'why,' we can tell them, 'I don't know, but that's how it is.' Why? (Mother shrugs her shoulders) How can a small human brain understand why! When you live it, you know! There's no problem, it's clear; it's like that because it's like that. It had to be that way - that's how it is.
You can find all sorts of explanations for it: consciousness would never have been so complete, joy would never have been so full, the realization would never have been so total, if one had not passed through ... all that. But these explanations are just to satisfy the mind. When you live in it, there's no need for explanations.
As for hoping to make people understand! ... The only thing that really matters is that they read your book with interest. Let them read it with interest; each one will imagine he has understood (and of course he will have 'understood'!), and through (I was going to say under) their interest, well, something will be awakened in their consciousness, a kind of first aspiration towards the need to realize - that's all. If you do that, good Lord, you have done a great thing!
Make them understand! How to understand? As long as one is there [at the mind level], one does not understand. One can imagine all sorts of things, explain all sorts of things, but ... with a pinch of common sense, you see very well that you don't explain a thing.
(Extract from the 'Cosmic Review' of 1906)
From sleep, I now emerge awakened.
I slept upon the westward waters and now I plunge into the ocean to fathom its depths. Its surface is the green of beryl, silvered by moonbeams. Below, the water is the blue of sapphire and already faintly luminous.
Reclining on the waves' silken folds, I descend; rocked from one undulating wave to another in a gentle rhythm, I am borne straight towards the west.  The deeper I go, the more luminous the water becomes, great silvery currents coursing through it.
Cradled from wave to wave, for a long while I descend deeper, ever deeper.
All at once, as I gaze above me, I glimpse something roseate; I draw nearer and discern what appears to be a shrub, as large as a tree, held fast to a blue reef. The denizens of the waters glide to and fro, myriad and diverse. Now I find myself standing upon fine, shining sand. I gaze about me in wonder. There are mountains and valleys, fantastic forests, strange flowers that could as well be animals, and fish that might be flowers - no separation, no gap is there between stationary beings and mobile. Colors everywhere, brilliant and shimmering, or subdued, but always harmonious and refined. I walk upon the golden sands and contemplate all this beauty bathed in a soft, pale blue radiance, tiny, luminous spheres of red, green and gold circulating through it.
How marvelous are the depths of the sea! Everywhere the presence of the One in whom all harmonies reside is felt!
Ever westward I advance, without weariness or hesitation. Spectacle succeeds spectacle in incredible variety; here upon a rock of lapis lazuli stretch fine and delicate seaweed like long blond or violet tresses; here great, rose-hued fortress walls, all streaked with silver; here flowers seem chiseled from enormous diamonds; here goblets, as beautiful as if carved by the most gifted sculptor, are filled with what appear to be droplets of emerald, alternately vibrant with light and shadow.
Presently I find myself between two rock walls of sapphire blue, upon a path flecked with silver; and the water becomes ever purer and more luminous.
A sudden turn in the path and I come to a grotto which seems fashioned of crystal, scintillating in prismatic radiance.
Standing there between two iridescent pillars is a very tall figure; his face, framed in short blond curls, is that of a very young man; his eyes are sea-green; he is clad in a pale blue tunic, and like wings upon his shoulders are great, snow-white fins. Beholding me, he steps aside against a pillar to let me pass. Scarcely have I crossed the threshold when an exquisite melody strikes my ears. The waters are all iridescent here, the ground aglow with glossy pearls; the portico and the vault, hung gracefully with stalactites, are opaline; delectable perfumes hover everywhere; galleries, niches and alcoves open out on all sides; but directly ahead of me I perceive a great light and towards it I turn my steps.  There are great rays of gold, silver, sapphire, emerald and ruby, radiating outward in all directions, born from a center too distant for me to discern; to this center I feel drawn by a powerful attraction.
Now I see that these rays emanate from a recumbent oval of white light encircled by a superb rainbow, and I sense that the one whom the light hides from my view is plunged into a profound repose. For long I remain at the outer edge of the rainbow, trying to pierce through the light and see the one who is sleeping encircled by such splendor. Unable to discern anything, I enter the rainbow, and thence into the white and shining oval. Here I see a marvelous being: stretched on what seems to be a mass of white eiderdown, his supple body, of incomparable beauty, is garbed in a long, white robe. His head rests on his folded arm, but of that I can see only his long hair, the hue of ripened wheat, flowing over his shoulders. A great and gentle emotion sweeps through me at this magnificent spectacle, and a deep reverence as well.
Has the sleeper sensed my presence? For now he awakens and rises in all his grace and beauty. He turns towards me and his eyes meet mine, mauve and luminous eyes with a gentle, an infinitely tender expression. Wordlessly he bids me a sublime welcome and my whole being joyously responds. Taking my hand, he leads me to the couch he has just left. I stretch out on this downy whiteness, and his harmonious visage bends over me; a sweet current of force enters wholly into me, invigorating, revitalizing each cell.
Then, wreathed by the splendid colors of the rainbow, enveloped by lulling melodies and exquisite perfumes, beneath his gaze so powerful, so tender, I drift into a beatific repose. And during my sleep I learn many beautiful and useful things.
Of all these marvelous things, understood without the noise of words, I mention only one.
Wherever there is beauty, wherever there is radiance, wherever there is progress towards perfection, whether in the Heaven of the heights or of the depths, there, assuredly, is found the form and similitude of man-man, the supreme terrestrial evolutor. [['Evolutor': a word coined by Mother. ]] 
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