“Tocqueville’s deepest belief,” historian Olivier Zunz writes at the beginning of “The Man Who Understood Democracy: The Life of Alexis de Tocqueville,” “was that democracy is a powerful, yet demanding, political form. What makes Tocqueville’s work still relevant is that he defined democracy as an act of will on the part of every citizen—a project constantly in need of revitalization and of the strength provided by stable institutions. Democracy can never be taken for granted. Once the aristocratic chain connecting all parts of society is broken, democracy’s need for vigilance, redefinition, and reinforcement is constant if it is to ensure the common good on which it must, in the end, depend.” This week on the podcast, Lewis H. Lapham speaks with Olivier Zunz, author of “The Man Who Understood Democracy: The Life of Alexis de Tocqueville.” Thanks to our generous donors. Lead support for this podcast has been provided by Elizabeth “Lisette” Prince. Additional support was provided by James J. “Jimmy” Coleman Jr.