Dr. Steven Pinker is a Cognitive Scientist and the Johnstone Family Professor of Psychology at Harvard University. He is an elected member of the National Academy of Sciences, a two-time Pulitzer Prize finalist, a Humanist of the Year, a recipient of nine honorary doctorates, one of Foreign Policy’s “World’s Top 100 Public Intellectuals” and Time’s “100 Most Influential People in the World Today,” and the bestselling author of 12 books including The Language Instinct, How the Mind Works, The Blank Slate, The Better Angels of Our Nature, Enlightenment Now, and most recently, Rationality: What It Is, Why It Seems Scare, and Why it Matters.

In this episode we discuss Dr. Pinker’s latest book Rationality, and how rationality is best defined as using knowledge to achieve a particular goal. We talk about the distinction between rationality as expressed in formal logic and ecological rationality, why people (including hunter-gatherers) may fail at logic puzzles but excel at those same puzzles when applied to reasoning about social or resource dilemmas. We also discuss cognitive biases that interfere with rationality, such as the “myside bias” and how the availability heuristic distorts our memories, and how these biases may be overcome through looking at the world in data. Additionally, we discuss how many irrational beliefs, such as conspiracy theories, are not failed attempts at objective descriptions of the world, but rather beliefs constructed using a “mythology mindset” that attempts to convey a moral message. Lastly, we discuss how rationality relates to enlightenment values, and the case to be (cautiously) made for rational optimism.