Jonathan Roberts, Page 51:
"And this is the manner of the Sons of Albion in their strength
They take the Two Contraries which are calld Qualities, with which
Every Substance is clothed, they name them Good & Evil
From them they make an Abstract, which is a Negation
Not only of the Substance from which it is derived
A murderer of its own Body: but also a murderer
Of every Divine Member: it is the Reasoning Power
An Abstract objecting power, that Negatives every thing
This is the Spectre of Man: the Holy Reasoning Power
And in its Holiness is closed the Abomination of Desolation
(Jerusalem, pl. 10, E151-2)
"This passage describes how the perceptions of an individual or a society are based on the contraries with which 'every substance' (i.e. phenomenal reality) is clothed and how those individuals or societies attach moral qualities to contraries, and from these they create an abstract scheme of reality which, Blake says, is a negation of reality itself. It is a negation because it is a mental abstraction that replaces reality itself.
"There is for Blake no means of describing nature other than from the human perspective that we have on it, and nature is therefore something interior to humans rather than exterior to them: its only perceivable life lies within us. The material universe therefore only takes shape as it is perceived:
'Nature has no Outline:
but Imagination has. Nature has no Tune: but Imagination has!
Nature has no Supernatural & dissolves: Imagination is Eternity'
(The Ghost of Abel, E269).
Thinking of nature as having a 'real' external existence outside of humanity is, for Blake, just another return to abstraction. Thus Blake writes:
"all are Men in Eternity [...]
as in your own Bosom you bear your Heaven
And Earth, & all you behold, tho it appears Without it is Within
In your Imagination of which this World of Mortality is but a Shadow.
[Jerusalem, pl. 71, E224]
This presents one of the most conceptually challenging aspects of Blake's work, which is when viewed from a 'cleansed' or 'eternal' perspective all things will appear in relation to our humanity, because for them to take any other form would lead back into the cycle of abstraction discussed earlier. When we look at nature what we see is our own humanity reflected, and each of us therefore sees slightly differently."
Seeing Blake's hesitancy to associate himself with any organization, we can surmise that it was not particular organizations he avoided, but what organizations represented to him. We know that he was acquainted with Moravians, Puritans, Swedenborgians, and Methodists. He joined for a short time the Royal Academy. But in the long run he found that organizations prevented individuals from exercising the perfect liberty of expressing their individual imaginations. To be true to his own humanity he eschewed associating himself with any system which had not come to him directly through the spirit within.
Copy A, Plate 32
He created one diagrammatic representation of his mythopoeic system, but ordinarily he communicated through images which required interpretation by the viewer or reader. A diagram is like an architectural drawing which answers the questions about how the building is to be constructed; Blake images ask us to answer many of the questions ourselves. Although this plate from Milton appears to be a diagram, it works as an image because so much must be added to it from a variety of extraneous locations for it to be understood.