In the April 30, 1978, edition of the Washington Post Book World, William McPherson wrote that The World According to Garp is: "A wonderful novel, full of energy and art, at once funny and horrifying and Heartbreaking…. You know The World According to Garp is true. It is also terrific.
Many of the initial reviews for The World According to Garp were equally enthusiastic. Christopher Lehmann-Haupt, in a favorable review published in the New York Times on April 13, 1978, recognized the book as "what is easily [Irving's] best novel to date." Mark Stevens, in a brief review published in the March 2, 1979, issue of the National Review, wrote that "The World According to Garp is the work of an extravagant imagination." In a review published in the April 23, 1978, issue of the New York Times Book Review, Julian Moynahan stated that "[Irving's] instincts are so basically sound, his talent for storytelling so bright and strong, that he gets down to the truth of his time."
Several critics admired Irving's skillful blending of humor and tragedy. Lehmann-Haupt noted that "we find ourselves laughing throughout The World According to Garp, and at some of the damndest things." Stevens wrote that Garp is "richly comic, its dialogue and scenes sometimes filled with a riotous energy worthy of the Marx Brothers." Several critics also commented favorably on "The Pension Grillparzer," the first short story written by Garp in the novel. Moynahan wrote that "the utterly charming 'The Pension Grillparzer'… glows at the heart of The World According to Garp." Michael Malone, in a review published in the June 10, 1978, issue of The Nation, wrote:
The short story, "The Pension Grillparzer," which the novelist, Garp, rightly suspects is the best thing he ever wrote, and which I suspect is the best thing in The World According to Garp—and further suspect Irving may think so too—is a beautiful fiction.
There were, however, critics who did not find Irving's novel "utterly charming." For example, critic Richard Gilman attacked what he believed was the novel's "fundamental insincerity." In the October 6, 1979, issue of the Nation, he wrote:
The World According to Garp is a model of its kind, and its kind is a seductive imitation of literary seriousness, an elegantly perpetrated, if not wholly deliberate, hoax. Irving's book is an extremely instructive example of how to have it all ways, an impressive feat of having one's literary cake while eating off commercial success."
Even some of the favorable reviews found flaws in Irving's novel. Moynahan, in noting a publisher's blurb saying that the book was "rich, humorous, and wise," wrote: "The book is certainly rich and humorous but it is more confused than wise." Malone, in his generally positive review, questioned what he called the novel's tendency to "explicate rather than embody" the idea that "comedy and death may be intrinsically joined."
Many academic articles on the novel have been published in various journals through the years as well. For example, Raymond J. Wilson examined the postmodern construction of The World According to Garp in the Fall 1992, edition of Critique: Studies in Contemporary Fiction. Wilson compares Irving's fiction to the works of John Barth and Robert Coover. He demonstrates that Irving's novel has a number of characteristics that identify it as a postmodern novel. For example, in The World According to Garp there is a "zone of the bizarre, where fantasy best expresses our sense of reality" as well as "a propensity for metafiction, in which writing draws attention to the techniques and processes of its own creation."
In another essay, published in Gender Studies: New Directions in Feminist Criticism, Janice Doane and Devon Hodges analyze the female characters in Garp. They contend that the strong female characters in the novel only serve to cover the "patriarchal power inscribed in traditional narrative conventions." They claim that in The World According to Garp "truth is structured in such a way as to guarantee paternal authority and to silence women no matter how much they speak." Of course, Irving, and many of his readers, would disagree with this conclusion.