In the process of preparing to testify in a divorce case, Brian had to study one of the strangest books he had ever come across, where religion, mathematics, and the apocalypse intersect. This week, we look at how a religious cult of number worshipers on the Italian coast gave rise to modern science, mathematics, philosophy, and music. In the interim 2500 years, as we have increased our knowledge of the universe using mathematics, we have lost the ability to explain why math is so successful at describing nature. Guest voices include Brian Frye, Errol Morris, Monte Johnson, and Gideon Rosen.

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High school students from around the country converge on the University of North Carolina for a weekend of moral dilemmas. We follow twenty-four of the nation's top ethics teams competing in the 2017 National High School Ethics Bowl, and take a whirlwind tour of moral philosophy in the process. Guest voices include Walter Sinnott-Armstrong, Geoff Sayre-McCord, Jeff Sebo, and students from high schools across the country.

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At the beginning of their adult lives, millennials are trying to find out what it means to be happy in their 20s, not knowing that they have no where to go but down. Meanwhile, three highly successful people find themselves at the bottom of life's happiness curve, and try to find their way back up. The show today is about a demographic inevitability, the midlife crisis, and how we seek happiness in the face of our approaching death. Two mid-lifers leave their careers to gamble on fulfillment, and one philosopher seeks answers to life's most common existential crisis. Guest voices include recent graduates of Vassar College, Philosopher Kieran Setiya, Neil Hayward, and Diane Hope.

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On our season finale, we follow a mother's love through the stages of life to seek wisdom about what love is, what love does, and why love happens. We follow five mothers at five different stages of motherhood, from the joys and anxieties of birth, letting go, coming back, being proud, and saying goodbye. We then turn to the philosophy of love and life, to figure out the role of love in the shape of a human life, and the significance of death in revealing the true value of our loved ones. Guest voices include Yael Goldstein Love, Tiffany Ward, Randy Scott Carroll, Diana Carroll, The J Family, Rachel Matlow, Elaine Mitchell, philosopher Susan Wolf, and philosopher Kieran Setiya. Special thanks to CBC radio's The Sunday Edition.

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Documentary film and science do not appear to have much in common, except that, philosophically, they have everything in common. Two men met in 1971 and had a disagreement, which turned into an assault, and then 45 years of disdain. One of them was the most cited philosopher of the 20th century, the other is one of the most influential documentary filmmakers of his generation. It was a disagreement that ran deep, right down to the nature of truth, history, reference, and the objects and limits of human inquiry.

Guest voices include Errol Morris, Lydia Patton, Thomas Rankin, James Challey, and Dan Epstein.

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Our ideas of manhood and womanhood determine the ways in which we raise and socialize our children, but how much does gender in a particular society depend on that society's relationship with violence? What happens when, all of a sudden, women are allowed to participate in a form of violence once reserved for men? This week, we investigate the effects and side effects of gender norms arising from militarism. Guest voices include two lieutenants in the US Army, LTC Naomi Mercer, Joshua Goldstein, Tom Digby, and Graham Parsons.

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One scientist decided to put the entire field of psychology to test to see how many of its findings hold up to scrutiny. At the same time, he had scientists bet on the success-rate of their own field. We look at the surprising paradoxes of humans being human, trying to learn about humans, and the elusive knowledge of human nature. Guest voices include Brian Nosek of the Center for Open Science, Andrew Gelman of Columbia University, Deborah Mayo of Virginia Tech, and Matthew Makel of Duke TiP. A philosophical take on the replication crisis in the sciences.

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After years of unusual episodes dating back to her childhood, Anita went to the doctor and was told there was nothing medically wrong with her. "She had a gift," she was told, and she was sent down the street to an ESP lab. Parapsychology is the scientific study of telepathy, clairvoyance, telekinesis, precognition, and spirits. Or is it? The field has been pushed to the fringes of science for decades now. In two episodes, I first follow the study of psychics, and then the mainstream sciences of human nature, to see if they differ enough to make one worthy of belief, and the other scorn. Guest voices include Anita Woodley, John Kruth and Sally Rhine Feather of the Rhine Research Center, and philosopher Massimo Pigliucci.

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Two records from 1983 achieved minor novelty fame, and then faded away, only to emerge 20 years later as the originators of a curious genre of pop music in the age of social media. This peculiar genre raises questions about how we should think about genre, musical aesthetics, and artistry in the time of industrially-produced music and digital reproduction. Guest voices include Jordan Roseman, aka DJ Earworm, Steve Stein, aka Steinski, philosopher Chris Bartel, and musicologist Christine Boone.

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With a small gesture of good will toward Syrian refugees, one woman incurred the wrath of evangelical Christians on social media. The resulting chaos helped write the next chapter in a thousand year-old controversy concerning Christianity, Islam, their shared origins, and the nature of God. Guest voices include Larycia Hawkins, Michael Mangis, Karly Bothman, Paul Griffiths, and Amir Hussain.

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