The best decision-makers aren't smarter — they use better mental models. These are the ideas that quietly improve almost every choice you make.
Second-order thinking: always ask 'and then what?'
Inversion: solve problems backward by asking how to fail
The real cost of anything is what you give up for it
Money already spent should never decide what you do next
Judge decisions by their quality, not their outcome
First-principles thinking: reason from what's true, not what's assumed
Base-rate neglect: the vivid story makes you forget the odds
The planning fallacy: why everything takes longer than you think
Urgent isn't the same as important
More choices can make you less happy
Decision fatigue: every choice drains the same limited tank
The overconfidence effect: we're far surer than we are right
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