ONE FLEW OVER THE CUCKOO'S NEST (311 pp.)Ken KeseyViking ($4.95).
The world of this brilliant first novel is Insideinside a mental hospital and inside the blocked minds of its inmates. Sordid sights and sounds abound, but Novelist Kesey has not descended to mere shock treatment or isolation-ward documentary. His book is a strong, warm story about the nature of human good and evil, despite its macabre setting. For as the boardinghouse provided a stock slice-of-life locale for another generation of writers, the sanitarium seems to appeal to many modern writers as a comparable microcosm...