One of the many things that used to baffle me was people’s behavior that’s evidently harmful to themselves. Take the case of Pune (a city in India where I live). It has simultaneously the lowest rate of helmet adoption and the highest number of two-wheeler casualties. How do you explain that?
Obviously, my confusion was a cognitive bias that impacts many people. It’s the mind projection fallacy: how I think is how other people must also be thinking. It’s an understandable bias as we know no other mind better than ourselves. We have direct access to our thoughts, but for others we can only guess why they’re behaving a certain way. My mistake was that I assumed that if I understand the tradeoff between the cost of wearing a helmet and benefits of avoiding a potential accident (conditioned on how frequently I use a two-wheeler * probability of an accident each time I use it), I’d be foolish not to wear a helmet. ...