The Irreversibility Test: How to Make Better Decisions
Before any major decision, ask one question: Can I reverse this in 6 months if I hate it?
If yes, move fast. Reversible decisions are options. Mistakes are learning opportunities.
If no, move slowly. Irreversible decisions require far more caution. The cost of error is permanent.
This simple principle reorganizes how you approach decision-making.
Reversible Decisions
A reversible decision is one you can undo or change without permanent consequence.
Examples: - New job (can leave within 6 months) - Moving to a new city (can move back) - Taking a course (can stop) - Starting a project (can abandon it) - Publishing a controversial idea (can clarify or retract) - Trying a new diet (can return to the previous one)
For reversible decisions, the threshold for trying should be low.
You don't need to be certain. You just need to think it might work and be willing to try it for a period. If it works, great. If not, you reverse course.
The benefit of being right far exceeds the cost of being wrong. Reversible mistakes are cheap.
Irreversible Decisions
An irreversible decision is one that cannot be undone or changed easily.
Examples: - Marriage (can divorce, but with enormous cost) - Having a child (cannot be undone) - Major geographic relocation with family (difficult to reverse) - Signing a 30-year mortgage (committed for 30 years) - Permanent modification to your body (surgery, tattoos) - Cutting off a relationship definitively
For irreversible decisions, the threshold for committing should be high.
You need to be quite certain. You need to think deeply about the downsides. You need to stress-test your assumptions. The cost of being wrong is permanent.
The Practical Power
Most people reverse the logic. They deliberate endlessly over reversible decisions and rush into irreversible ones.
"Should I try this new job? Let me research for three months." (Reversible — you can change within 6 months)
"Should I propose to this person? Let's decide right now." (Irreversible — the cost of error is enormous)
This is backwards.
The antifragile approach: - Reversible decisions: spend an hour thinking, then try - Intermediate reversibility: spend a week thinking, then try - Irreversible decisions: spend a month thinking, then decide
Real Examples
Moving to a new city:
If you have a remote job and no family commitments, moving is reversible. You can move back within a year. The decision threshold should be low. "Might I like living in Portland? Let's try it."
If you're tied to a specific company and have school-age children, moving is irreversible. The threshold should be much higher. "Are we absolutely sure this is where we want to raise our children?"
Changing careers:
If you have savings and portable skills, changing careers is reversible. You can return to the previous career within a few years if it doesn't work. The threshold can be low. "Is this new career potentially better? Let's try."
If you have a family depending on your income and specialized skills, changing careers is irreversible. The threshold should be much higher.
Starting a business:
If you can start part-time while keeping your job, starting a business is reversible. You can close it down if it doesn't work. The threshold for trying should be low.
If you need to quit your job and liquidate savings to start, the business is irreversible (in practical terms). The threshold should be high.
Edge Cases
Some decisions are in the middle — mostly reversible but with some permanent costs.
Publishing: You can publish something controversial and later retract it, but the initial publication is permanent. Some people will always remember it.
Decision: publish? Threshold is moderate. Not "definitely sure" but more than "might be interesting."
Hiring: You can fire someone, but there's cost and awkwardness. The decision is somewhat irreversible.
Decision: hire? Threshold is moderately high. You need to be fairly confident it's the right fit.
Stress Testing
Once you've identified whether a decision is reversible, stress test it.
Reversible decision stress test: "If this goes terribly wrong, can I recover in 6 months? Do I have the resources? Is there a plan to unwind it?"
If yes to all, the threshold for trying is low.
Irreversible decision stress test: "If this goes terribly wrong, what's the permanent consequence? Can I live with it? Have I considered the worst case?"
If the worst case is acceptable, the threshold for committing can be lower. If the worst case is unacceptable, don't do it.
The Practical Application
Apply this test to any major decision:
- Is this reversible?
- If yes, set a short trial period. Try it.
- If no, stress-test the worst case. Then decide carefully.
This principle alone improves decision-making significantly.