Every mental model is a lossy compression — it sacrifices detail for speed. That tradeoff is the point. But the American pragmatist philosopher Charles Sanders Peirce noticed something more unsettling: the models we reach for fastest are the ones that were reinforced under past conditions, not the current ones. He called this the 'fixation of belief' — the way inquiry stops the moment we feel the discomfort of uncertainty dissolve, even if the belief that dissolved it is outdated. The problem isn't that you have models. It's that relief feels identical whether the model is accurate or merely familiar. In business and technology especially, the model that once worked spectacularly becomes the one most resistant to revision — because it carries the weight of past wins. Peirce's prescription wasn't skepticism; it was a specific kind of alertness: notice when a belief is functioning as an anxiety reducer rather than a map. That's the moment to probe it, not defend it.

What belief about your market, your users, or your team feels so settled it never comes up in meetings anymore — and what conditions would have to change before it should?

Drawing from American Pragmatism — Charles Sanders Peirce (The Fixation of Belief, 1877)