In the late twentieth century, many social scientists and other social commentators came to characterize the world as evolving into an “information society.” Central to these claims was the notion that new social uses of information, and particularly application of scientific knowledge, are transforming social life in fundamental ways. Among the supposed transformations are the rise of intellectuals in social importance, growing productivity and prosperity stemming from increasingly knowledge-based economic activity, and replacement of political conflict by authoritative, knowledge-based decision-making. We trace these ideas to their origins in the Enlightenment doctrines of Saint Simon and Comte, show that empirical support for them has never been strong, and consider the durability of their social appeal.