Radiolab’s Ellen Horne and Oscar-winning filmmaker Alex Gibney kick off Lies We Tell by discussing a simple untruth: The Pulitzer Prize–winning war historian Joseph Ellis lied about serving in Vietnam. The rest of Ellis’s record has been vetted by other academics and seems to check out, so the hosts attempt to make sense of what appears to be a singular departure. Each episode stands on the conceptual building blocks from the last, creating something akin to a book of essays. The show so effectively breaks down the notion of lying that by the final episode, the hosts have made several convincing cases that it’s a foundational tool for human existence; little distinguishes a strongly held belief from a lie. Narrative making, which contains degrees of truth and untruth, is required for us to organize the world around us. Sometimes we need to fool ourselves, just a little, to go after our dreams. Lies We Tell features plenty of antagonists, but lying isn’t one of them.