The Lions lose

About this video

Before the big match on Saturday, Lina's friends argue about who will win. Lina says it could go either way: maybe the Lions, just. The Lions lose 3-0. On Monday Lina tells everyone she knew the Lions would lose, that you could see it coming. She isn't lying; she really feels she knew. But on Saturday she said the Lions might win. What happened to her memory?

Once we know how something turned out, it begins to look obvious. The signs that pointed to it stand out, the signs that pointed the other way fade, and we remember expecting it all along. This is hindsight bias, the "I knew it all along" feeling. In 1975 the psychologists Baruch Fischhoff and Ruth Beyth asked people how likely some events were before they happened, and afterwards asked them to remember what they had said. People remembered being much surer of what really happened than they had been. They had rewritten their own memory without noticing.

Hindsight seems harmless, but it fools us in three ways. We think we are better at guessing than we are, because we only remember the times we knew. We judge other people unfairly: after something goes wrong, we say they should have seen it coming, though beforehand it may not have been clear at all. And we learn the wrong lesson, because if everything looks obvious afterwards, we never learn how unsure we were or what we missed. The cure is simple: write your predictions down before you know the answer, with how sure you are, and afterwards read what you wrote, not what you remember. When you judge a decision, ask not whether the result is obvious now, but what could have been known then. This video goes with the I Knew It All Along lesson of Knowledge Level 2 on Knaph.

Transcript

1. 0:00Saturday, Lina says the match could go either way. Maybe the Lions, just.
2. 0:05The Lions lose 3-0. On Monday Lina says, I knew it all along.
3. 0:11She isn't lying. Knowing the result quietly rewrote what she remembers expecting.
4. 0:17So we think we guess well, blame others unfairly, and learn the wrong lesson.
5. 0:23Write predictions down, with how sure you are. Then read what you wrote.
6. 0:29Judge by what could be known then.