This book provides a comprehensive analysis of the dynamics of capital accumulation and distribution over the last few centuries. The author argues that the rate of capital return in developed countries is persistently greater than the rate of economic growth, leading to high levels of wealth inequality. The book further suggests that the level of income inequality is not primarily a result of differences in individual labor income but rather the result of differences in capital ownership and the income derived from it. The author proposes a global tax on wealth to prevent soaring inequality.

This book delves into the historical patterns of inequality, arguing that significant reductions in inequality have only ever been brought about by cataclysmic events, which the author terms as the "Four Horsemen": war, revolution, state collapse, and plague. Through a comprehensive examination of societal structures from the Stone Age to the modern era, it presents a compelling case that peaceful reforms have rarely led to lasting decreases in inequality. The work challenges readers to confront the uncomfortable reality that significant improvements in equality have often been forged in the crucible of immense human suffering, thereby questioning the prospects for achieving future equality without such extreme catalysts.