Through their viral TED Talks, bestselling books, and counterintuitive remedies for complicated problems, psychologists and allied social scientists have become leading thinkers of our time. “Power posing” and “grit,” they say, can help individuals overcome entrenched inequality in schools and the workplace. Positive psychologists inspired the U.S. Army to spend hundreds of millions of dollars on an intervention geared toward preventing PTSD in its combat soldiers. The implicit association test swept the nation on the claim that it can reveal unconscious biases and reduce racism in police and human resources departments. But what if much of the science underlying these blockbuster ideas is dubious or fallacious? What if Americans’ long-standing preference for simplistic self-help platitudes is exerting a pernicious influence on the way behavioral science is communicated and even funded, leading respected academics and the media astray?