Excerpted from "Freethinkers: A History of American Secularism" by Susan Jacoby with permission of Henry Holt.

To describe the last quarter of the nineteenth and the first decade of the twentieth centuries as a golden age of freethought is to suggest not that a majority of Americans were persuaded by rationalist or antireligious arguments but that those arguments reached a much broader public than they ever had in the past. Unlike eighteenth-century deists, nearly all of whom identified with Jeffersonian democracy, American freethinkers of the late nineteenth century were anything but unified in their political views, which ran the gamut from anarchism to Spencerian conservatism. Freethinkers might be Democrats, rock-ribbed Republicans, or, on occasion, socialists with either a capital or a small s.

The one political concern that did unite all freethinkers was their support for absolute separation of church and state, which translated into opposition to any tax support of religious institutions-especially parochial schools. For the most part, tax support of religious schools had been a nonissue on a national basis before the Civil War-although New York City's Catholic leadership had pushed unsuccessfully in the 1840s for government subsidy, long established in many European countries, of religious education. By the 1870s, when the growth of the older Irish Catholic community and new immigration from the Catholic countries of Europe began to transform the ethnic and religious makeup of most large cities, the financing of parochial school education became a divisive issue throughout the country.

Nineteenth-century opposition to tax subsidies for parochial schools is often portrayed by modern supporters of religious school vouchers as a manifestation of singleminded anti-Catholicism, but that was certainly not true for freethinkers. Deists of Jefferson's generation fought tax support for religious institutions at a time when the only influential American religious sects were Protestant. Their nineteenth-century successors were unquestionably appalled when the Roman Catholic Church became the first large religious denomination to establish its own school system in America, and they viewed the growth of Catholic schools as a threat to the expansion of public education-a major goal of all social reformers after the Civil War. In addition, Pius IX's well-publicized denunciations of religious pluralism, secular government, modernism, and science reinforced long-standing American suspicions, on the part of devout Protestants as well as freethinkers, of "papists." But freethinkers, secularists, rationalists, infidels, agnostics, and atheists, whatever they call themselves or are called by others-have always taken the position that the American government has no business spending any money on any institution whose purpose is the promotion of any religion.

Because Americans of different faiths were accustomed to religious liberty in practice as well as in theory, separation of church and state-however compelling as a constitutional principle-was not an issue that touched the daily lives of most citizens. Arguments over the mention of God on coins or tax exemption of church property could not provide freethinkers with a basis for appeal to the larger public. The absence of a political focus-a problem unknown to anticlerical Europeans, who formed a political opposition to governments based on monarchy, narrow economic privilege, and church authority-is generally considered a weakness of the American freethought movement. But this lack of identification with a particular political point of view or party was also a strength, in that it enabled freethinkers to exert a strong influence on other reform movements that were nonpartisan in character. For if freethinkers did not have a political platform, they nevertheless agreed on a wide range of social, cultural, and artistic concerns, which generated such fierce debate in the decades after the Civil War that they would form a template for the nation's "culture wars" a century later. These included free political speech; freedom of artistic expression; expanded legal and economic rights for women that went well beyond the narrow political goal of suffrage; the necessity of ending domestic violence against women and children; dissemination of birth control information (a major target of the punitive postal laws, defining birth control information as obscene, that bore the name of Anthony Comstock); opposition to capital punishment and to inhumane conditions in prisons and insane asylums; and, above all, the expansion of public education.

American secularists were dedicated to the improvement of free cultural and educational institutions for pragmatic as well as philosophical reasons. The unprecedented postwar expansion of public schools, libraries, and museums-the latter two supported by private philanthropists as well as public funds-contributed greatly to the willingness of Americans to entertain, if not necessarily to adopt, unfamiliar ideas. Free public education for the many rather than the few was essential to the secularist vision of a society in which every individual, unhampered by gatekeepers who sought to control the spread of dangerous knowledge, could go as far as his or her intellect would permit. In the view of freethinkers, the most pernicious gatekeepers were religious authorities; thus, education must be both secular and publicly financed. Indeed, by the 1870s the word secularist was used not only as a general philosophical term but as a specific definition, in either the affirmative or the pejorative sense, of those who advocated public schooling free of religious content.