The role and importance of the enlightenment continues to be debated. The early start is traced back to the 1660s in England.This article reviews that past and the twist and turns these ideas have taken through later centuries. "Even more important was the Enlightenment notion of freedom of expression. In our age, we think of technological change as natural and obvious; indeed, we consider its absence a source of concern. Not so in the past: inventors were seen as disrespectful, rebelling against the existing order, threatening the stability of the regime and the Church, and jeopardizing employment. In the eighteenth century, this notion slowly began to give way to tolerance, to the belief that those with odd notions should be allowed to subject them to a market test." And the nature of nationalism: "In the nineteenth century, Europeans used their new technology to oppress, exploit, and murder non-Europeans; in the late nineteenth century, they replaced the transnational ideals of some enlightened thinkers wit:h an often ugly nationalism that taught the masses that the way to show love for their country was to hate its neighbors; and in the first half of the twentieth century, they turned on one another with a brutality and destructiveness that history had never witnessed before."