Decide in the Light
Precommit calmly so fear cannot rewrite sound decisions during turmoil
- Difficulty
- Moderate
- Time to result
- ~ongoing to results
- Steps
- 6
- Confidence
- 98%
Decide in the Light is a precommitment discipline for high-pressure situations. During a calm period, the decision-maker analyzes facts, records the thesis, identifies risks, and specifies evidence that would justify changing course. When markets or circumstances become frightening, a physical or written cue prompts a pause: is the underlying evidence different, or does the situation merely feel terrible? The original plan remains in force when only emotion has changed, but it is revised when predefined invalidating evidence appears. This avoids two common failures—freezing like a deer in headlights and abandoning a sound decision during panic. The method also requires comfort with being wrong, because disciplined decisions improve process rather than guaranteeing every outcome.
Origin
Christine Hurtsellers kept a picture of a deer in headlights on the trading floor and used the phrase about decisions made in light versus darkness to reinforce calm investment discipline. Extracted from Masters in Business.
Core principles
- 01Calm analysis is more reliable than panic
- 02Emotional discomfort does not prove a decision is wrong
- 03Precommitment protects against reactive behavior
- 04Being wrong is a normal part of investing and decision-making
- 05Plans should change when facts change, not merely when feelings intensify
How to run it
- 1
Analyze in calm conditions
Evaluate the decision when you can think deliberately about facts, probabilities, and consequences.
Pro tip Delay non-urgent commitment until emotional intensity has subsided.
Watch out A calm mood does not compensate for missing evidence.
- 2
Write the thesis
Record the decision, supporting facts, assumptions, expected outcome, and acceptable risk before turmoil arrives.
Pro tip Keep the record short enough to consult quickly under pressure.
Watch out A vague thesis can be retrofitted to justify any action.
- 3
Set invalidation conditions
Specify which observable changes would require reducing risk, reversing the decision, or gathering new evidence.
Pro tip Distinguish thesis failure from ordinary volatility.
Watch out Precommitment must not become stubbornness.
- 4
Install a pause cue
Use a visible reminder, checklist, or waiting period to interrupt automatic reactions during fear or euphoria.
Pro tip Choose a memorable image or phrase, as Hurtsellers did with the deer photograph.
Watch out A reminder helps only if it is consulted before acting.
- 5
Compare facts with the plan
Ask whether the evidence has changed or whether only emotional conditions have changed.
Pro tip Have a trusted colleague challenge the comparison when stakes are high.
Watch out Do not dismiss new evidence merely because it arrives during a crisis.
- 6
Hold or revise deliberately
Maintain the decision when the thesis remains intact, and change it promptly when an invalidation condition is met.
Pro tip Document why you held or revised the decision for later review.
Watch out Judging discipline solely by the immediate outcome encourages hindsight bias.
In the wild
An investment team enters a selloff with documented security theses, risk limits, and invalidation conditions. As prices gap lower, the team checks whether issuer fundamentals have changed rather than selling solely because the market feels frightening.
→ The team avoids reflexive liquidation while retaining permission to exit positions whose evidence has deteriorated.
A founder commits to a six-week market test based on customer interviews and defines cancellation thresholds in advance. A harsh first week creates anxiety, but the founder waits for the agreed evidence rather than abandoning the test immediately.
→ The launch is evaluated against its original evidence and thresholds instead of short-term emotion.
Common mistakes
Treating discomfort as evidence
Fear can be intense even when the original thesis remains intact, especially near market lows.
Refusing to update
The framework protects sound decisions from emotion; it does not excuse ignoring genuinely changed facts.
Keeping the thesis implicit
Without written assumptions and invalidation conditions, memory will reshape the original reasoning after events change.
Is it for you?
Best for
Investors and leaders who must act consistently through volatile, frightening, or euphoric conditions.
Not ideal for
Decisions whose original evidence has materially changed or whose downside requires immediate emergency action.
From the transcript
“get comfortable being wrong”
“am I being that deer in the headlights?”
“don't doubt in the darkness things you decided in the light.”
From the episode
Christine Hurtsellers on the Business of Trust (Podcast)
Christine Hurtsellers