I was thinking today about the old practical joke involving dog poo wrapped in toilet paper, dumped on your doorstep, and set alight. The intuitive response to seeing something burning on your doorstep is to stamp it out. In this case, leaving you with warmish dog poo all over your footwear.
A shitty joke - literally - but what it demonstrates is that if you can hijack people's intuitive responses, you can induce us to act against our own best interests.
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