The rise of economic inequality over the past generation has become a hot-button issue. In this e‑book Cato senior fellow Brink Lindsey offers a fresh new interpretation of the growing class divide along educational lines. The good news, he argues, is that modern economic growth has made us smarter. Growth breeds social complexity, complexity imposes increasingly heavy demands on our mental capabilities, and people respond by investing heavily in “human capital” — that is, valuable knowledge and skills. In recent decades, however, the connection between economic development and cognitive development has broken down for large segments of American society. The demand for human capital has continued to grow, but the supply has stalled. Lindsey explores the cultural roots of this problem and offers policy prescriptions for reviving broad-based human capital accumulation.