This presidential address argues that capitalism must be understood as an epochal phenomenon, that is, as a historically specific and temporally limited form of life with social and temporal dynamics that set it off from previous eras of history and that are not destined to last indefinitely. Capitalism’s most distinctive feature—sustained secular economic growth in per capita terms—has brought great benefits to the human race, not only increasing economic well-being but endowing people with bigger, stronger, and more resilient bodies and radically increased life spans. It has also made possible an astounding increase in society’s technical, educational, and scientific powers. The experience of sustained economic growth has led to a particular sense of time as open-ended and progressive—making possible modern historical consciousness. Meanwhile, the relentless commodification of social relations under capitalism has tended to free people from domination based on personal status, but also to subject them to more abstract forms of domination. Creative destruction, which is capitalism’s key mechanism for producing sustained economic growth, has also produced an unmasterable cyclical pattern of boom and bust, creating new forms of insecurity at the same time that it tends to lift people out of absolute poverty. Capitalist development has always been spatially uneven. There is reason, however, to think that the capitalist era may be approaching its end. The shape of the postcapitalist era will depend on how well we collectively make use of the powers that the capitalist era has produced—science and technology, to be sure, but also the critical historical consciousness that lies at the heart of social science history.