What happens when the public's understanding of a global event is hijacked by online psuedo-experts? How should scientists express uncertainty when everyone's suspicious? Was Anthony Fauci the victim of a crazed conspiracy, or is there something fishy in the official origins of Covid-19?

The inside story of how the Covid lab leak hypothesis went mainstream is just one of the tales which the science journalist Elizabeth Finkel investigates in her new book. Josh is still suspicious of the Wuhan lab so the two of them debate the wet market, gain of function research, China's secrecy, RFK's disinformation, Occam's razor, and how to do good science in a post-truth era.

Finkel is the co-founder and former Editor-in-Chief of COSMOS magazine and a regular contributor to Science magazine. Her new book is Prove It: A Scientific Guide for the Post-Truth Era.