Shakespeare?

in the book shakespeare the world as stage by bill bryson theres a paragraph on pg 105 where it says "o paradox black is the badge of hell the hue of dragons and the school of night" Shakespeare from Love's Labour's Lost "what exactly he meant by "the school of night" is really anyones guess" how come nobody mentions Raleighs school of night which Marlowe was ociated with? im only 13 and dont know much about these guys so does anybody else know how come it wasn't brought up?