When the rate of return on capital exceeds the rate of growth of output and income, as it did in the nineteenth century and seems quite likely to do again in the twenty-first, capitalism automatically generates arbitrary and unsustainable inequalities that radically undermine the meritocratic values on which democratic societies are based. (Introduction)

Importance: This quote is a concise statement of Piketty's argument throughout the book. It draws together in one sentence all the elements of his thought: the economic mechanism driving inequality, the historical trajectory of this mechanism, and the ideological foundations upon which the forces of inequality must be stemmed.

Before presenting my results in detail, it is best to proceed by stages. The purpose of Part One of this book is to introduce certain basic notions. In the remainder of this chapter, I will begin by presenting the concepts of domestic product and national income, capital and labor, and... (chapter 1)