His reference at the end is from this famous verse of Blake's:
Now I a fourfold vision see And a fourfold vision is given to me Tis fourfold in my supreme delight And three fold in soft Beulah's night And twofold always. May God us keep From single vision & Newtons sleep.
Doesn't that marvellous phrase 'single vision' describe so accurately the sort of corpohacks and pols who are fulminating so madly at the moment at the uppity plebs everywhere suddenly not doing what they're told; and when it's all for their own good too, as Nanny knows best...? See the Greer article for more unpacking of this idea. Just struck me that what he describes fits - for example - the ridiculous salaried stiffs at the Fraud so accurately.
As to what Blake thought about Newton, and the several-centuries-long thrust towards the extreme, thankfully-now-moribund, reductive-materialism of today's science, of which Isaac and his epoch-changing Principia Mathematica was such a notable part - well, that's a whole other story.