In 1962, Thomas Kuhn noticed something that should have been obvious but wasn't: scientists don't abandon a flawed theory when evidence contradicts it. They add patches, exceptions, and workarounds — sometimes for decades — until the accumulated mess finally collapses under its own weight. He called this the pre-paradigm crisis, the strange phase where everyone quietly knows the model is broken but keeps using it anyway. The mental models you use to run a business or read people work exactly the same way. You don't drop them when they fail; you explain away the failure. The model that once helped you — 'my best people need autonomy, not process,' or 'users always know what they want' — becomes load-bearing architecture, and you build your next ten decisions on top of it. Kuhn's practical gift isn't the famous word 'paradigm.' It's the diagnostic question buried inside his work: when did I last count how many exceptions I'm carrying? If your mental model now requires more exceptions than predictions, you're not using a model anymore — you're preserving a belief.

What's one mental model you're currently defending with exceptions — and what would you have to admit if you discarded it?

Drawing from Philosophy of Science (Kuhnian paradigm theory) — Thomas Kuhn