Entertaining these days, to find, in the rather bloodless, incestuous body of American literary criticism, a young critic who allows himself to become joyously tipsy on what he's read. The author, with the courage of unpublished youth, has constructed a daring rope ladder of organic theory up and into the highlands of American literature. Mr. Van Nostrand has been reading Emerson, Whitman, Melville, Hart, Crane, Adams, Poe, James, Faulkner and Williams. He loosely nets them into closer scrutiny with a startling metaphorical view of what he calls ""cosmologies."" ""Each (work) represents a struggle to build a true cosmos. . .a parochial scheme which demonstrates the unseparate wholeness of all being according to the single vision of the author."" But the core of these ""romantic"" works lies in the authors' assumption that the reality of their vision, their doctrine, may reach into and interpret the ""intractable"" world around and beyond them. The process of the struggle is the subject,' the expression, of his work. Slyly entitling his chapters ""paradigms,"" Mr. Van Nostrand constantly reinforces his intention of playing out and reeling in the luminous totality of the works with the aim of exploration rather than analysis. Stratospheric sorties where most popular critics fear to tread. Very special, difficult, but ingratiating.