In this second interview with Dr. David Robert Grimes, author of the indispensably excellent book, The Irrational Ape, I began by asking him about the reductive fallacy, before moving onto a related essentialising bias known as the No True Scotsman fallacy. I then asked my guest about two woefully widespread mental shortcuts, namely the anecdotal fallacy and the post hoc ergo propter hoc fallacy, which literally means “after this therefore because of this,” but is often stated as correlation does not equal causation. Dr. Grimes also reminded listeners that the plural of anecdote is never data. We spent some time discussing various issues pertaining to statistics, including the difference between relative and absolute risk, the nature of statistical significance, the meaning of a P-value, and the so-called replication crisis in social science and in biomedical research. I then asked Dr. Grimes to explain sensitivity and specificity, two crucially important attributes pertinent to all tests for diseases. Understandably, these concepts have gained even greater relevance during the Covid pandemic. In The Irrational Ape, Dr. Grimes draws from a 2005 paper by John Ioannidis called ‘Why Most Published Research Findings are False’ to provide six guidelines to assess the validity of research findings, which we spent some time discussing. I also asked him about some ways to distinguish between science and pseudoscience. At the time we recorded the interview, Dr. Grimes was about to pen a piece for The Observer about the Wuhan Lab Leak theory, averring that the virus was engineered at the Wuhan Institute of Virology, which he argues is a conspiracy theory that violates the principle of Occam’s Razor. He helpfully explained what this is for those who might not know and is another handy weapon in one’s critical thinking armoury. Near the end of this once again insightful and enjoyable interview, my guest pointed out how liberating it can be to admit you do not know something. As he said, “don’t believe anything until the evidence is in,” which is a reminder of the kind of humility and intellectual honesty we should all try to cultivate. Official website: https://www.davidrobertgrimes.com/ Twitter account: http://www.twitter.com/drg1985 Instagram account: https://www.instagram.com/david_robert_grimes/ Buy The Irrational Ape: https://www.amazon.co.uk/Irrational-Ape-Flawed-Critical-Thinking/dp/1471178250 https://www.waterstones.com/books/search/term/the+irrational+ape+david+robert+grimes Dr. Grimes’ article about the Wuhan Lab Leak Theory: https://www.theguardian.com/commentisfree/2021/jun/13/newly-respectable-wuhan-lab-theory-remains-fanciful Twitter account for Skeptically Curious: https://twitter.com/SkepticallyCur1 Patreon page for Skeptically Curious: https://www.patreon.com/skepticallycurious