Assumption Excavation

First-principles reasoning is often described as reasoning from fundamentals. In practice the useful activity is narrower: finding the assumptions nobody has said out loud and asking whether they are true.

The excavation questions, applied to a stated requirement: why is this needed? — repeatedly, until the answer is a business outcome rather than a solution. Who says so, and when did they say it? — many constraints are decisions made years ago under conditions that no longer hold. What would happen if it were not true? — which distinguishes an obstacle from a catastrophe. Is this a constraint or a convention?

The findings that recur: a requirement that is a solution in disguise ("we need a message queue" rather than "orders must not be lost if the downstream is unavailable"); a constraint that expired, such as a policy written for a data centre the organisation no longer has; and a performance target inherited from a system with different characteristics.

The counterweight that keeps this from being tiresome: most conventions encode real experience, and re-deriving everything from fundamentals is slow and frequently rediscovers why the convention exists. Excavate where the stakes are high or the constraint is blocking something valuable — not as a general habit applied to every decision.