Completed in 1970 and published the following year, Grendel was the first of John Gardner's novels to bring him not just critical but popular success. The novel was praised as a literary tour de force and named a book of the year by Time and Newsweek magazines. As a professor of English specializing in medieval literature, Gardner had been teaching Beowulf, the source of inspiration for Grendel, for many years at various colleges. A relatively minor character in Beowulf, Grendel is a symbol for "darkness, chaos, and death," according to critic John M. Howell in Understanding John Gardner. In Gardner's version, however, Grendel becomes a three-dimensional character with, in Howell's words, "a sense of humor and a gift for language." Grendel even has a weakness for poetry. As a would-be artist, Grendel strives, however comically, to escape from his baseness. Such is the power of art, Gardner seems to be saying, that even a monster can be affected by it. Gardner also develops the theme of heroism as another moral force that enables society to advance by elevating Unferth, a minor character in the original poem, to a major character and foil for Grendel. Similarly, Gardner builds up the role of Grendel's mother to emphasize, through her inarticulateness, the importance of language in the development of civilization. Gardner also creates a relationship between Grendel and the dragon (another minor character in the original epic) in order to expand the concept of nihilism—the belief that there is no purpose to existence. Through these changes, Gardner is able to develop themes that recur not only in Grendel but throughout his other works: the struggle between good and evil, the clash between order and disorder, the hero's sacrifice and achievement of immortality, and the importance of art and the artist as a means of affirming the moral meaning of life.