In 1936, the sociologist Louis Wirth, in his preface to the American edition of Karl Mannheim’s Ideology and Utopia, wrote:

It seems to be characteristic of our period that norms and truths which were once believed to be absolute, universal, and eternal, or which were accepted with blissful unawareness of their implications, are being questioned. In the light of modern thought and investigation much of what was once taken for granted is declared to be in need of demonstration and proof. The criteria of proof themselves have become subjects of dispute. We are witnessing not only a general distrust of the validity of ideas but of the motives of those who assert them. This situation is aggravated by a war of each against all in the intellectual arena where personal self-aggrandizement rather than truth has come to be the coveted prize. Increased secularization of life, sharpened social antagonisms and the accentuation of the spirit of personal competition have permeated regions which were once thought to be wholly under the reign of the disinterested and objective search for truth. 1

This observation could have been made anytime from the late nineteenth century through the present. While presented as peculiar to its moment—the 1930s—it would seem to be equally at home in the Progressive Era thought of William James, Elsie Clews Parsons, Henry Adams and Walter Lippmann or the so-called “postmodern” era of Kuhnian paradigms, Foucauldian critique, critical race theory and feminist theories of knowledge. The rhetoric of a world in which timeless verities and absolute truths are called into question by epistemological uncertainty, rapid social change, cultural conflict and a rooting of knowledge and belief in personal experience and interested motive, is a rhetoric that is pervasive throughout the long twentieth century. Wirth wrote as if his moment was to be distinguished from that immediately preceding it, when the authority of established truths went unquestioned, as if Darwinism, statistical thinking, Freudian psychology and the scientific agnosticism of the late nineteenth century were not already unsettling received knowledge and calling into question the authority of rational thought and objective truth. Like Wirth looking back to a prelapsarian era, the critics of postmodern relativism of the 1980s and 1990s imagined an era—Wirth’s own—prior to the 1960s as one in which the authority of science was absolute, the fixed categories of male and female were given in nature, and moral truths were matters of broad consensus in the philosophical tradition from Aristotle to Kant.