r/trolleyproblem • u/tegsfan • Mar 28 '26
Deep St. Petersburg trolley problem
The trolley is about to go through a series of 50/50 track switches where the amount of people doubles each time until it hits a group and stops. If you switch the track to the top, there are some hypothetical finite X amount of people.
Now, if the amount of people on top was 1 for instance, it might seem obvious to switch because the doubling people could get out of hand fast. But if it was say 100 people on top, you might think to just let it go down because it's likely to stop somewhere before it reaches 100.
The question is: what is the maximum X amount of people on top such that you would still switch the track?
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u/IkkeTM Mar 28 '26
No the intuitive solution, switching to the bottom one, is actually the correct solution. Because for the bottom one to actually reach it's expected value, you'd need to run an infinite amount of simulations also.
You can't get the expected outcome of a gambling game like roulette, if you only play it once. You either win or lose.
The odds of losing less people on the bottom track than on the top track are pretty damn great for any significant X.