Thought Experiment

When empiricism is out of reach, run a disciplined counterfactual: one isolated change, fixed conditions, step-by-step mechanism, and a hard bound on implications.

When to Use

• You need behavior under failure, scale, or policy you cannot cheaply trigger or measure (region outage, 100x load, one-way architecture).
• A decision is expensive or irreversible and a mental trace can surface break points before commit.
• Edge cases are too costly to stage, but a mechanistic chain can still expose missing controls.

When NOT to Use

• A cheap real test exists (load test, flag, query, spike) → run the test; do not substitute imagination.
• Adversarial security attack-path work → use red-team structure, not free-form scenarios.
• You already know the mechanism and only need a decision under known facts → decide; do not dramatize.
• Vague "what if everything" brainstorming without a single isolated variable → tighten or stop.

Procedure