Mythbusters episode where they have to call Omelas busted because it turns out there's an upper limit of how much a person can suffer and it's surprisingly low, the child wouldn't be able to take on even a small town's worth of suffering
also they test it by putting Jamie in the hole and he says something like "Well it wasn't all that bad, but I can see it being upsetting for a kid" afterward
actually no, they literally stole candy from a baby and made it cry in one episode, I think they'd put a kid in a hole to see what happens
also, same episode as this
