The stakes have never been higher. The world is more divided than ever before, and a significant part of the issue is that we can't agree on what counts as 'true'.
This week's episode features Dr Kiki Sanford: host of the hugely popular 'This Week in Science' and science communicator extraordinaire. Here, she takes on the core challenge of vaccine scepticism, the mechanics of how we come to decisions on what we think is true, and how to make the most of a PhD.