This episode features Professor Dean Simonton, who has spent his life quantitatively studying geniuses, from Einstein to Mozart. Dean and Julia discuss his views on whether IQ is important, whether some innovations are "in the air" at given points in history, whether the "10,000 hours = mastery" theory promoted by Malcolm Gladwell is accurate, and more.

This episode features neuroscientist Ed Boyden discussing two inventions of his that have revolutionized neuroscience: optogenetics and expansion microscopy. Ed and Julia talk about Ed's approach to coming up with good ideas, why he prefers reading old science to new science, his big-picture plan for what he wants to solve in his career, and his take on the rationalist versus Hayekian debate over how to make important progress.

This episode features physicist Sabine Hossenfelder, author of Lost in Math, arguing that fundamental physics is too enamored of "beauty" as a criterion for evaluating theories of how the universe works. She and Julia discuss the three components of beauty (simplicity, naturalness, and elegance), why physicists think it's reasonable to put their trust in beauty, and why this might be merely a symptom of other underlying problems with physics as a discipline.

This episode features Stuart Ritchie, intelligence researcher and author of the book "Intelligence: All That Matters." Stuart responds to some of the most common conceptual objections to the science of IQ testing. Can we even define intelligence? Aren't there lots of different kinds of intelligence? How do we know the tests are measuring intelligence at all instead of something like motivation or familiarity with the style of testing? Does it undermine the meaningfulness of IQ as a metric that people can improve over time, with practice, or over generations?

This episode features cognitive psychologist Christopher Chabris discussing his research on "collective intelligence" -- why do some teams perform better than others at a wide variety of tasks? Julia discusses potential objections to the findings and how gender-related publication bias should affect our interpretation of them. In the second half of the episode, Julia and Chris discuss why people get so upset at companies like Facebook and OKCupid for doing experiments on their users, and whether that's fair.

This episode features Annie Duke, former pro poker player and author of the book Thinking in Bets: Making Smarter Decisions When You Don't Have All the Facts. Julia and Annie debate why people tend to ignore the role of luck in their decisions, whether expressing uncertainty makes you seem weak, and how people end up engaging in "defensive decision-making," where they're not trying to make the best call so much as simply avoid being blamed for bad outcomes.

Developmental psychologist Alison Gopnik explains why modern parenting is too goal-oriented. Alison and Julia discuss whether anything parents do matters, whether kids should go to school, and how kids learn discipline if you don't force them to do things. They also discuss Alison's reservations about Steven Pinker's book Enlightenment Now, and her concerns about potential downsides of modernity.

When people argue on the internet, you never expect anyone to actually say "You know what, that's a good point, you've changed my view somewhat." But Change My View, a fast-growing subreddit founded by Kal Turnbull, is an exception to the rule. Julia and Kal discuss the culture of Change My View, what makes it such an oasis for reasonable discussion on the Internet, and what we've learned about what motivates people to change their minds or not.

This episode features economist Michael Webb, who recently co-authored a paper titled "Are ideas getting harder to find?" It demonstrates that the number of researchers it takes to produce a technological innovation has gone up dramatically over time. Michael and Julia discuss various possible explanations for why this is happening, along with several challenges to his paper.

Simine Vazire is a professor of psychology, the author of the blog, "Sometimes I'm Wrong," and a major advocate for improving the field of psychology. She and Julia discuss several potential objections to Simine's goal, how to handle criticism, and Simine's psychology research on the question: How self-aware are people about the way they behave?