Rav Aharon Lichtenstein is considered an expert on John Milton, and Paradise Lost is an incredible influence on his hashkafa (not to mention a profound inspiration on Lord of the Flies and on western civilization, in general). CS Lewis has even impacted his hashkafa. Machon Herzog, associated with Gush, has even pioneered literary study of Tanakh.
Many fine works of literature offer tremendous insight into human nature and psychology, and hence, I am methodologically making my way through many of the great books of the Western Canon.