Why Your Best Ideas Come in the Shower (A 1926 Answer)

You fight a bug all afternoon, give up, and the answer arrives in the shower the next morning. It feels like luck. In 1926, Graham Wallas, a co-founder of the London School of Economics, argued it isn't: it's stage three of a four-stage process, preparation, incubation, illumination and verification. We follow two of the stories Wallas built on: Henri Poincaré's fifteen fruitless days before a breakthrough that arrived as he stepped onto a bus, and Hermann von Helmholtz's best ideas coming on slow walks up wooded hills. Then we look at what later research says about breaks, walking and sleep, where the model falls short, and the one stage modern engineers skip every day. Chapters 0:00 Cold open 1:24 The man who mapped the aha 2:52 Stage one, preparation 4:50 Stage two, incubation 7:24 Stage three, illumination 9:23 Stage four, verification 10:37 What the model gets wrong 11:57 The afternoon that wasn't wasted 13:13 Your four-stage experiment Sources Graham Wallas, The Art of Thought (1926): https://archive.org/details/theartoft... Henri Poincaré, Mathematical Creation, in Science and Method: https://www.bayesianspectacles.org/he... Sio & Ormerod (2009), Does incubation enhance problem solving? Psychological Bulletin: https://pubmed.ncbi.nlm.nih.gov/19210... Wagner et al. (2004), Sleep inspires insight, Nature: https://research.uni-luebeck.de/en/pu... Oppezzo & Schwartz (2014), walking and creative thinking, Stanford: https://news.stanford.edu/stories/201... Du, Gordon & Tolmie (2025), mind wandering during incubation (on later replications): https://pmc.ncbi.nlm.nih.gov/articles... Alex and his Thursday bug are a made-up example. #Creativity #SoftwareEngineering #DeepWork #ProblemSolving #EngineersMotivation