In this week’s podcast, we're replaying an episode that first aired earlier this year, but seems more relevant now than ever. Sam is joined by two writers to talk about the perennially fraught issue of race. There’s a wide consensus that discrimination on the basis of race is wrong; but what actually *is* race? Does it map onto a meaningful genetic or scientific taxonomy? Does it map onto a lived reality - is it possible to generalise, say, about 'black' experience? And can we or should we opt out of or ignore it? Adam Rutherford and Thomas Chatterton Williams approach these issues from very different angles: the former, in How To Argue With A Racist, brings genetic science to bear on the myths and realities of population differences; while the latter describes in Self-Portrait in Black and White: Unlearning Race how after half a lifetime strongly attached to the idea of his own blackness, the arrival of his blonde haired and blue eyed daughter made him rethink his worldview.