Blake seems to have unusual access to the unconscious world. Like a spring of living water it welled up into his consciousness in the form of images which he translated for us into words and pictures. Like the description Blake gives of Eternity as an ever active interchange of a multitude of super-sensory movements, the unconscious is a reservoir for the imagination.
Four Zoas, Page 21, (E 310)
Then those in Great Eternity met in the Council of God
As one Man for contracting their Exalted Sense
They behold Multitude or Expanding they behold as one
As One Man all the Universal family & that one Man
They call Jesus the Christ & they in him & he in them
Live in Perfect harmony in Eden the land of life
Consulting as One Man above the Mountain of Snowdon Sublime
Jerusalem, Plate 88, (E 246)
"When in Eternity Man converses with Man they enter
Into each others Bosom (which are Universes of delight)
In mutual interchange. and first their Emanations meet
Surrounded by their Children. if they embrace & comingle
The Human Four-fold Forms mingle also in thunders of Intellect
But if the Emanations mingle not; with storms & agitations
Of earthquakes & consuming fires they roll apart in fear
For Man cannot unite with Man but by their Emanations
Which stand both Male & Female at the Gates of each Humanity"
In her book of essays on the basis of poetic expression, Defending Ancient Springs, Kathleen Raine looks for the common sources which illumine the poets. In this passage Raine in speaking of the collective unconscious which can speak to us in dreams and visions connecting our minds through the image world which we all share. (Page 114)
"Jung came nearer than did Freud to the traditional doctrine, as taught by those alchemists, Gnostics, and neo-Platonists whom he himself took for masters; for he realized that dreams do not so much conceal as embody meaning, and that this comes from their source within the psyche - or beyond it - normally inaccessible to the waking mind. Not all dreams come from the same level; and besides the personal elements recognized by Freud, Jung, was led to believe in what he calls a 'collective unconscious' because it is so as a rule, though at times accessible to consciousness. This is the ancient anima mundi, the soul of the world, whose images at times, waking or in dreams, we behold with amazement, so beautiful and so fraught with meaning do these appear. Because this world is not personal but common to all, its symbols are intrinsically intelligible as Freud's symbols from the personal unconscious are not.
The symbolic images come, of necessity, from the perceptible world; for this world is, in the nature of things, and unalterably, the 'given', inseparable from our human nature as incarnate beings; all the knowledge of the soul must come to it in terms of this world of embodiment - that is to say in symbolic form. Truly understood the entire world is one great symbol, imparting, in a sacramental manner, by outward and visible signature, an inward and spiritual essence."
This passage may intimate a way Blake reacted to placing his interior visions into outward forms:
Europe, Plate 1, (E 61)
"Ah mother Enitharmon!
Stamp not with solid form this vig'rous progeny of fires.
I bring forth from my teeming bosom myriads of flames.
And thou dost stamp them with a signet, then they roam abroad
And leave me void as death:
Ah! I am drown'd in shady woe, and visionary joy."
Blake seemed to have paid a price for transforming vision to poetry and images.
Illustration to Edward Young's Night Thoughts
Here is the link to Kathleen Raine's video speaking about Blake and imagination.