Costello analyzes paradigms of world history, focusing on seven twentieth-century historians, from H. G. Wells to William H. McNeill. He interprets central models of the history of civilizations as responses to modernism and as efforts to rescue meaningful patterns of history as a whole.

Costello locates his study in the post-Nietzschean context, in which the "death of God" and modernism's threat to progressive ideology stimulated a perception of the crisis of Western civilization. He analyzes H. G. Wells's sense of "progress threatened," in which the catastrophic potentials of modernity demand a world state; the cyclical "decline of civilizations" theories of Oswald Spengler, Arnold J. Toynbee, Pitirim Sorokin, Christopher Dawson, and Lewis Mumford; and the ecological metahistory of William H. McNeill.

These historians, Costello finds, develop a pattern of the past that incorporates a history of the future—a pattern that perpetuates those they perceive in their study of the rise and fall of civilizations. Costello describes a reciprocal process between the historians' analyses of the past and their personal visions of the future. Such visions, he suggests, present the historian with moral imperatives that demand action in line with the hidden ends of history.

Each chapter includes a biographical sketch, a study of the intellectual influences on its subject's thought, an evaluation of his goals, and a brief review of relevant criticism. The various theories are examined in light of each historian's moral and philosophic intentions and polemical goals in writing.