Mr. Miller is a fine story teller at his best—which is in the opening section of ["A Canticle for Leibowitz"], depicting the medieval reprise. But when his time-machine shifts gears into the neo-Renaissance, it stalls in a bog of quasi-historical novelese. These chapters are overrun with thanes and clans and polyglot hugger-mugger concerning a baronial type named Hannegan II, who operates out of the Red River country, and has designs on the states of Laredo and Denver.

A graver misdemeanor is the author's heavy-handed approach to allegory; his far too explicit moralizing dulls the luster of his imaginative format.

Martin Levin, "Incubator of the New Civilization," in The New York Times Book Review, March 27, 1960, pp. 42-3.