Race is not a biological reality. Racism thrives on our not knowing this. Racist pseudoscience has become so commonplace that it can be hard to spot. But its toxic effects on society are plain to see—feeding white nationalism, fueling hatred, endangering lives, and corroding our discourse on everything from sports to intelligence. Even well-intentioned people repeat stereotypes based on “science,” because cutting-edge genetics are hard to grasp—and all too easy to distort. Paradoxically, these misconceptions are multiplying even as scientists make unprecedented discoveries in human genetics—findings that, when accurately understood, are powerful evidence against racism. We’ve never had clearer answers about who we are and where we come from, but this knowledge is sorely needed in our casual conversations about race. How to Argue With a Racist emphatically dismantles outdated notions of race by illuminating what modern genetics actually can and can’t tell us about human difference. We now know that the racial categories still dividing us do not align with observable genetic differences. In fact, our differences are so minute that, most of all, they serve as evidence of our shared humanity.