Nagarjuna, the 2nd-century Buddhist logician, built his entire philosophical system on a single uncomfortable move: he applied every concept to itself. If something is 'permanent,' is the concept of permanence itself permanent? If something is 'empty of inherent existence,' is emptiness itself empty? His method — called *prasanga*, reductio by self-application — wasn't nihilism. It was a scalpel for detecting concepts that quietly exempt themselves from the very rules they impose on everything else. The mental models you use to lead are almost certainly doing this. 'Don't overcomplicate things' is a model — but have you ever applied it to your collection of mental models? 'Trust the process' is a model — but have you examined the process by which you adopted it? The models that have never been turned back on themselves are the ones doing the most invisible work, which means they're also the ones most likely to be quietly wrong. The practical discipline Nagarjuna points toward is this: once a month, take your most relied-upon heuristic and ask whether it survives contact with itself.

Which heuristic do you use most often — and have you ever tried running it through its own logic to see if it holds?

Drawing from Madhyamaka Buddhist philosophy — Nagarjuna