Online trolls and political disinformation. Cancel culture and Twitter pile-ons. We’re living in a time when truth itself is under perpetual assault by growing numbers of our fellow citizens (and more than a few Russian bots) who simply don’t want to believe anything that they — well — didn’t already want to believe. This rising tide of illiberalism from across the political spectrum has many of us yammering on until we turn blue about respectful disagreement and the marketplace of ideas. But what if defenders of truth are missing the most fundamental conceptual revolution at the very core of this American experiment and the enlightenment — of western civilization itself? Jonathan Rauch argues we must know the constitution of knowledge exists if we are to have any hope of defending it.   This frame-shifting conversation is offered in partnership with Florida Humanities as a part of a multi-year series “Unum: Democracy Reignited,” exploring the past, present and future of the American idea — as it exists on paper, in the hearts of our people, and as it manifests in our lives. We thank The Andrew W. Mellon Foundation for their generous support of this program and the Pulitzer Prizes for their partnership.