Consider the following decision situation, first introduced by analytic philosopher Peter Singer:
You’re walking past a muddy pond and realize that a child is drowning in it, and that its life depends on your (in)action. As it happens, you’re wearing a newly bought suit and expensive shoes, which you need for professional purposes and which cost you $3,400. Rushing into the pond and saving the child poses no risk to you at all, but it will ruin your suit and shoes – you’ll have to replace them for $3,400, which amount you’d otherwise have spent on some luxury goods. What would you do?
Evidence-based development economics shows that in the real world out there, we can expect to actually save a life for $3,400. Since many people in rich countries possess thousands of dollars that are not essential to them, they’re faced with this choice multiple times over.