Assumption

An assumption is an untested belief that has been allowed to function as established fact within a decision process. It enters the system silently — often through precedent, convenience, or inherited opinion — and compounds its influence the longer it remains unexamined. Assumptions are not errors in themselves; they become dangerous when they are invisible to the people acting on them.

In decision infrastructure

Governed decision-making requires that assumptions are surfaced, declared, and stress-tested before they carry weight. In a properly engineered decision infrastructure, every material assumption is logged as a dependency — something the conclusion rests on, and something that can be audited when conditions change. The discipline is not to eliminate assumptions, which is impossible, but to make them visible and reviewable. An assumption register is as important as the evidence file.

Failure pattern

When assumptions go unexamined, institutions make confident decisions on unstable foundations. The board approves a strategy built on market conditions that no longer hold. The executive acts on a competitor analysis that assumed stable regulation. The failure is not in the decision itself but in the invisible load-bearing belief that was never tested. Post-failure reviews almost always trace the collapse back to an assumption that everyone treated as settled fact.

Practical test

Can you name the three most consequential assumptions behind your current strategy — and state what evidence would invalidate each one?