A mental model, once it works, starts to do something insidious: it begins selecting which evidence reaches you. The 11th-century Persian philosopher Al-Ghazali described this in his spiritual autobiography *Deliverance from Error* — not as a failure of logic, but as a failure of what he called *taqlid*, the unconscious deference to inherited frameworks. His argument was precise: the problem isn't that we use frameworks; it's that successful frameworks generate social proof, and social proof replaces continued questioning. The model stops being a probe and becomes an authority. For product leaders, this plays out in a specific way — the mental models that got your team to product-market fit quietly become the criteria by which you evaluate whether you've achieved it again. You're no longer measuring against reality; you're measuring against a previous self. Al-Ghazali's corrective was radical doubt directed not at conclusions, but at the instruments of reasoning themselves. Not 'is our thesis wrong?' but 'is the framework we're using to evaluate the thesis still the right instrument for this stage of the problem?'

What would remain of your current product strategy if you removed the one mental model you've relied on longest — not replaced it, just temporarily removed it?

Drawing from Islamic Philosophy / Sufi Epistemology — Al-Ghazali (Deliverance from Error / Al-Munqidh min al-Dalal, c. 1109 CE)