Proof: The Art and Science of Certainty

“Even mathematical notions of proof [are] not always as robust... as they might seem,” according to this thought-provoking analysis. Kucharski (The Rules of Contagion), an epidemiology professor at the London School of Hygiene and Tropical Medicine, uses historical examples to explore the challenges of establishing objective truths through math and science. For instance, he discusses how Abraham Lincoln’s efforts to use Euclidian logic to prove that slavery was at odds with America’s founding principles failed because such reasoning requires both parties to agree on certain foundational axioms, which Lincoln’s pro-slavery opponents didn’t subscribe to. Modern science determines what counts as a statistically significant result based on an “arbitrary” cutoff, Kucharski contends, describing how in the 1920s statistician Ronald Fisher first proposed disregarding findings if “the probability of obtaining a result that extreme by chance” is more than 5% because that figure was just large enough to validate his recent research. Lamenting how scientists have exploited this threshold, Kucharski notes that for every 10 experiments, “there’s a 40 percent chance that one will cross the traditional... cutoff purely by chance,” leading some researchers to repeat experiments until they get the desired result and omit mention of the unsuccessful iterations in publication. The straightforward prose renders the quirks of research methodology approachable for lay readers. This edifies. (May)