Premortem
Also called prospective hindsight — psychologist Gary Klein's procedure, endorsed by Daniel Kahneman and extended to personal life by Daniel Levitin.
Postmortem: after a disaster, experts figure out what went wrong.
Pre-mortem: before committing, imagine the plan failed catastrophically, identify what could go wrong, then prevent those failures or minimize damage.
Organizational Use (Kahneman)
Before a group commits to a plan, imagine it failed and write the history of how. Legitimizes dissent and surfaces risks optimism suppressed. Fights planning-fallacy, wysiati, and organizational lethargy when bad reference-class data gets noted then ignored.
Complements reference class forecasting and checklists — organizations can impose orderly procedures humans resist individually.
Personal Use (Levitin)
Levitin's Montreal cascade — lockout → broken window → forgotten passport → missed seat — taught him that stress impairs judgment in ways you can't detect in the moment. The pre-mortem response is systems installed while calm:
- Designated places for keys, passport, glasses
- Travel backups (cloud photos of documents)
- Physical fail-safes (combination lock with spare key)
- Pre-written medical questions (NNT, side effects, quality of life)
The principle: don't manufacture the chain of reasoning on the spot when cortisol is active. Pre-mortem the questions and systems before you need them.
Medical decisions are the stress-test case — but the frame applies to financial and social decisions too.
Connections
- stress-impairs-judgment — why pre-mortem must happen before stress, not during
- number-needed-to-treat — example of a question to pre-mortem for medical visits
- designated-place-system — physical pre-mortem against lost-essential failures
- planning-fallacy — organizational failure mode premortem targets
- implementation-intentions — if-then pre-commitments are a lighter-weight cousin
- decision-quality-vs-outcome — premortem improves process quality before outcome is known