[Phineas is] concerned mainly with the psychological problems of American male adolescents. Admirers of Mr. Knowles's well-known novel, A Separate Peace, will recognize in the title story, as well as in "A Turn in the Sun," much of the source material for A Separate Peace. Competent, sophisticated, and a master of place description, Mr. Knowles also dramatizes as well as anyone I know the torments—especially the torments of ostracism—suffered by the sensitive and intelligent male adolescent. But when he gets off this subject he seems lost. In "The Peeping Tom," for example, he seems desperately and unsuccessfully to be searching for a subject worthy of his ambition and talent. (pp. 275-76)