Weber's work, for the most part, is an attempt to explain modernity. One of the most important trends he perceived in modern life was what he called "demystification," which described the replacement of a religious worldview by rationality and science. This occurred alongside, and was reinforced by, a process known as "rationalization." This was associated with both science and rationality, but also modern capitalism, which sought to reduce every aspect of human life and social relations to the accumulation of profits.

Weber's most famous work, The Protestant Ethic and the Spirit of Capitalism, contended that the Protestant virtues of frugality and work ethic in pursuit of a "calling" were conducive to the rise of capitalism. In time, these religious mores were stripped of their spiritual underpinnings and simply became virtuous inasmuch as they contributed to the production of wealth. Society was organized into bureaucracies, which gave rise to "organizational men" who worked in highly specialized vocations. Weber described the emergence of bureaucracy as an "iron cage" and the new type of person that worked within them as a "specialist without spirit."

Rationalization is certainly evident in modern life. Modern people are besieged by online advertisements based on algorithms that ascertain their tastes. People in a variety of fields have seen their jobs altered, if not replaced, by a variety of technologies. As for the persistence of religious values, Weber did not argue that people would not continue to find meaning in spiritual sources. Rather, he would likely be struck by the extent to which religion as an institution reflected these concerns—the creation of "mega-churches," for example, or the rise of "self-help" themes in modern faiths. He would likely be interested in the ways that such things as yoga became commodified and institutionalized. Indeed, the concept of "late capitalism" sometimes described by sociologists as a salient feature of twenty-first century life owes much to Weber's rationalization thesis.