Decisions

How to Decide: 8 key ideas

by Annie Duke

The core ideas of How to Decide, each in under a minute, written in our own words. Want the full depth? Get the book.

1. IDEA 1 OF 8

   Good decisions can have bad outcomes

   Duke, a former professional poker player, warns against resulting: judging a decision only by its outcome.

   A good decision can turn out badly because of luck, and a bad decision can turn out well.

2. IDEA 2 OF 8

   Hindsight distorts memory

   Duke describes hindsight bias, believing after the fact that an outcome was obvious.

   This makes it harder to learn. So we may feel we should have known better, and then we do not learn what we truly could not have predicted.

3. IDEA 3 OF 8

   Map possible outcomes

   Duke suggests drawing decision trees, listing possible outcomes for each option.

   This makes choices clearer. Seeing the branches on paper lets you compare paths side by side, rather than holding all the possibilities in your head at once.

4. IDEA 4 OF 8

   Estimate probabilities

   Duke encourages estimating how likely each outcome is, even roughly.

   Thinking in probabilities improves decisions. Instead of saying something is likely or unlikely, putting even a rough number on it helps you compare risks and spot your own overconfidence.

5. IDEA 5 OF 8

   Consider preferences

   Duke suggests considering how much you would like or dislike each outcome.

   Combining preferences with probabilities helps choose. A very likely outcome that you hardly care about may matter less than an unlikely one that would change your life.

6. IDEA 6 OF 8

   Use the outside view

   Duke recommends looking at how similar situations usually turn out, not just your own case.

   This reduces bias. If most people who tried a similar plan struggled, that is a strong clue about how yours may go too.

7. IDEA 7 OF 8

   Decide quickly when stakes are low

   Duke describes the happiness test: if a choice will not matter much in a year, decide quickly.

   Save time for big decisions. The idea is that you spend your careful thinking on choices that really shape your life.

8. IDEA 8 OF 8

   Imagine failure in advance

   Duke recommends pre-mortems, imagining a decision has failed and asking why.

   This helps spot risks. Because people are tempted to be overly optimistic, imagining the failure first helps the team speak up about problems they might otherwise ignore.