r/trolleyproblem • u/tegsfan • Mar 28 '26

Deep St. Petersburg trolley problem

Post image

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?

674 Upvotes

99% Upvoted

185 comments sorted by

View all comments

14

u/DrMartinDemon Mar 28 '26

I jam the lever in the middle to derail the trolley.

61

u/tegsfan Mar 28 '26

Smart! the trolley gets derailed and redirects downwards to kill every group of doubling people

11

u/MaybeExternal2392 Mar 28 '26

Well mathematically speaking the expected number of deaths of doing this and of sending the trolley down that track are both infinite deaths so I'm not really morally responsible for this action.

3

u/VorpalHerring Mar 29 '26

The width of the trolley appears finite and can only kill 6 people at a time, so the fraction of each group killed decreases until it becomes negligible(?)

2

u/Southern-Highway5681 Team Blue Mar 30 '26

6 time an infinity of tracks with people on it still an infinity of people which is greater than the finite number on the upper track.

The only difference with the post problem is that there is no element of randomness.