MENTAL WORKS

At times Blake gave the impression that he was opposed to science because of his criticism of Newton as the prime exponent of the scientific method in his day. However there was much that he admired about science. Blake was an experimenter and inventor himself devising methods and materials for engraving and painting, and for poetic expression. He objected to forming rigid systems of thought that limited the use of the imagination. And he objected to eliminating non sensory input from the equation of science. He felt that reasoning based only on material data led to sterile, repressive systems which restricted consciousness rather than expanding it.
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Blake often placed art and science in the same category. He considered that when practiced as endeavors of the imagination they both contribute to the building Jerusalem. Science as practiced by reductionists and empiricists he considered destructive to humanity and the kingdom of heaven. Mental activity expressed in art and science was not to be confused with generalized, mechanical, deterministic, materialistic philosophies which Blake associated with Bacon, Newton and Locke.

Jerusalem, Plate 77,(E 232)
"What is the joy of Heaven but Improvement in the
things of the Spirit? What are the Pains of Hell but Ignorance,
Bodily Lust, Idleness & devastation of the things of the Spirit[?]
Answer this to yourselves, & expel from among you those who
pretend to despise the labours of Art & Science, which alone are
the labours of the Gospel: Is not this plain & manifest to the
thought? Can you think at all & not pronounce heartily! That to
Labour in Knowledge. is to Build up Jerusalem: and to Despise
Knowledge, is to Despise Jerusalem & her Builders.
And remember: He who despises & mocks a Mental Gift in another;
calling it pride & selfishness & sin; mocks Jesus the giver of
every Mental Gift, which always appear to the ignorance-loving
Hypocrite, as Sins. but that which is a Sin in the sight of cruel
Man, is not so in the sight of our kind God.
Let every Christian as much as in him lies engage himself
openly & publicly before all the World in some Mental pursuit for
the Building up of Jerusal

Descriptive Catalogue , (E 542)

All these things are written in Eden.

The artist is an inhabitant of that happy country, and if
every thing goes on as it has begun, the world of vegetation
and generation may expect to be opened again to Heaven,
through Eden, as it was in the beginning.

Jerusalem, Plate 6
Los the Blacksmith

Vision of the Last Judgment , (E 565)
The Last Judgment is an Overwhelming of Bad Art & Science.
Mental Things are alone Real what is Calld Corporeal Nobody Knows
of its Dwelling Place is in Fallacy & its Existence an
Imposture Where is the Existence Out of Mind or Thought Where is
it but in the Mind of a Fool.

Jerusalem, Plate 55, (E205)
"Let the Indefinite be explored. and let every Man be judged
By his own Works, Let all Indefinites be thrown into Demonstrations
To be pounded to dust & melted in the Furnaces of Affliction:
He who would do good to another, must do it in Minute Particulars
General Good is the plea of the scoundrel hypocrite & flatterer:
For Art & Science cannot exist but in minutely organized Particulars
And not in generalizing Demonstrations of the Rational Power.
The Infinite alone resides in Definite & Determinate Identity
Establishment of Truth depends on destruction of Falshood
continually"

The pursuit of Art & Science under the guidance of Imagination is life itself leading to the 'Establishment of Truth.'
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