PERFECT UNITY

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Joseph of Arimathea preaching to the inhabitants of Britain

Blake saw that the Perfect Unity of Homer's poetry was apparent in its parts (minute particulars) as much as in its totality. The unifying force came not from what the author included or omitted but from his own inner truth or spirit from which he was writing. The ability to trust his imagination instead of his reasoning power enabled him to connect with the underlying reality which transcends individual experience.

The Perfect Unity of Homer's poetry included the bad with the good. It was not about morality but about intrinsic character. Blake considered bad and good to be contraries whose differences would be reconciled when error was annihilated. The substance of poetry is furnished not by the Reasoning Abstract but by the Imagination which has access to the Holy Spirit - connecting the image of God within each with the one in whose image man is made. 

ON HOMERS POETRY, (E 269) 
"Every Poem must necessarily be a perfect Unity, but why Homers is

peculiarly so, I cannot tell: he has told the story of
Bellerophon & omitted the judgment of Paris which is not only a
part, but a principal part of Homers subject
  But when a Work has Unity it is as much in a Part as in the
Whole. the Torso is as much a Unity as the Laocoon
  As Unity is the cloke of folly so Goodness is the cloke of
knavery  Those who will have Unity exclusively in Homer come out
with a Moral like a sting in the tail: Aristotle says Characters
are either Good or Bad: now Goodness or Badness has nothing to do
with Character. an Apple tree a Pear tree a Horse a Lion, are
Characters but a Good Apple tree or a Bad, is an Apple tree
still: a Horse is not more a Lion for being a Bad Horse. that is
its Character; its Goodness or Badness is another consideration.
  It is the same with the Moral of a whole Poem as with the Moral
Goodness
of its parts Unity & Morality, are secondary considerations &
belong to Philosophy & not to Poetry, to Exception & not to Rule,
to Accident & not to Substance. the Ancients calld it eating of
the tree of good & evil.
  The Classics, it is the Classics! & not Goths nor Monks, that
Desolate Europe with Wars.
                                                             
ON VIRGIL                            
Sacred Truth has pronounced that Greece & Rome as Babylon &
Egypt: so far from being parents of Arts & Sciences as they
pretend: were destroyers of all Art.  Homer Virgil & Ovid confirm
this opinion & make us reverence The Word of God, the only light
of antiquity that remains unperverted by War.  Virgil in the
Eneid Book VI. line 848 says Let others study Art: Rome has
somewhat better to do, namely War & Dominion
  Rome & Greece swept Art into their maw & destroyd it     a
Warlike State never can produce Art.  It will Rob & Plunder &
accumulate into one place, & Translate & Copy & Buy & Sell &
Criticise, but not Make.
  Mathematic Form is Eternal in the Reasoning Memory.  Living
Form is Eternal Existence.
  Grecian is Mathematic Form
  Gothic is Living Form"

Descriptive Catalogue, (E 544)
"The human mind cannot go beyond the
gift of God, the Holy Ghost.  To suppose that Art can go beyond
the finest specimens of Art that are now in the world, is not
knowing what Art is; it is being blind to the gifts of the
spirit."

Vision of last Judgment, (E 554)
 "The Last Judgment when all those are Cast away who trouble
Religion with Questions concerning Good & Evil or Eating of the
Tree of those Knowledges or Reasonings which hinder the Vision of
God turning all into a Consuming fire  Imaginative Art &
Science & all Intellectual Gifts all the Gifts of the Holy Ghost
are [despisd] lookd upon as of no use & only Contention
remains to Man then the Last Judgment begins & its Vision is seen
by the [Imaginative Eye] of Every one according to the
situation he holds"

Milton, Plate 25 [27], (E 122)
"And you shall Reap the whole Earth, from Pole to Pole! from Sea to Sea
Begining at Jerusalems Inner Court, Lambeth ruin'd and given
To the detestable Gods of Priam, to Apollo: and at the Asylum
Given to Hercules, who labour in Tirzahs Looms for bread    
Who set Pleasure against Duty: who Create Olympic crowns
To make Learning a burden & the Work of the Holy Spirit: Strife."

Jerusalem, Plate 74 (E 229)
"The Spectre is the Reasoning Power in Man; & when separated      
From Imagination, and closing itself as in steel, in a Ratio
Of the Things of Memory. It thence frames Laws & Moralities
To destroy Imagination! the Divine Body, by Martyrdoms & Wars

Teach me O Holy Spirit the Testimony of Jesus! let me
Comprehend wonderous things out of the Divine Law" 
.