But one interesting way to try and inject some rationality is to think from an outsider’s perspective. So here’s what happens. When you think about your own life, you’re trapped within your own perspective. You’re trapped within your own emotions and feelings and so on. But if you give advice to somebody else, all of a sudden you’re not trapped within that emotional combination, mish-mash, complexity and you can give advice that is more forward-looking and not so specific to the emotions.

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So for example, in one experiment, we asked people, we said, "Look, you went to your doctor. They gave you this diagnosis. You know that the thing that the doctor recommended is much more expensive and there are other things that would be much cheaper. Would you go for a second opinion?" And people say, "No, my doctor recommended it. How could I not take their advice? How could I say, 'Can you please refer me for a second opinion?'" Then we asked another group. We said, "Here is the situation. If this happened to your friend, would you recommend that they go for a second opinion?" People said, "Absolutely. How could you not go for a second opinion?" So one idea is to try and get ourselves from an outside perspective. You look at the situation and then you say to yourself if this was about somebody else, somebody I love and care about and then when this situation what would I advise them? And you would realize that often your advice will be different and often a more rational, useful perspective.

A useful trick from Dan Ariely on how to think more rationally.