The contact hypothesis is an old idea in social psychology. It posits that under the right circumstances, bringing people from different groups together can reduce prejudice. In this episode, we discuss a new field experiment by Salma Mousa testing whether putting Iraqi Christians and Muslims on soccer teams together can rebuild social cohesion after war. Part of our conversation focuses on the direct implications of this work for the contact hypothesis. We also discuss how this study stands out against some common patterns in social science research. Why, despite the long history of research and intuitive appeal of the contact hypothesis, have no studies like this been done before? How did this paper benefit from integrating rigorous quantitative methods with a careful understanding of history and context? How did a commitment to not just the letter, but also the spirit, of preregistration keep the conclusions aligned so well with the data? Plus: We answer a letter about whether the COVID pandemic means this is an especially bad time to start a Ph.D. program. Links: Building social cohesion between Christians and Muslims through soccer in post-ISIS Iraq, by Salma Mousa Can playing together help us live together? Commentary by Elizabeth Levy Paluck and Chelsey Clark Twitter thread by Betsy Paluck The Black Goat is hosted by Sanjay Srivastava, Alexa Tullett, and Simine Vazire. Find us on the web at www.theblackgoatpodcast.com, on Twitter at @blackgoatpod, on Facebook at facebook.com/blackgoatpod/, and on instagram at @blackgoatpod. You can email us at firstname.lastname@example.org. You can subscribe to us on iTunes or Stitcher. Our theme music is Peak Beak by Doctor Turtle, available on freemusicarchive.org under a Creative Commons noncommercial attribution license. Our logo was created by Jude Weaver. This is episode 83. It was recorded on August 19/20 (US/AUS), 2020.