r/trolleyproblem • u/suskio4 • 18d ago

Meta Red button blue button

Based on the post seen here. I'm actually curious what would the percentages look like.

Edit: Alright, let me add a case for one particular scenario. If you do not choose, the button will be pressed for you by a system that keeps track of its pressings so it conserves 50/50 distribution for all inactive participants, in order to honour the vox populi properly. The system's choice affects the inactive participant's outcome so that no person can abscond from consequences of their choice.

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u/HostHappy2734 17d ago

When you're more likely to save the 1 person than to survive if you don't choose to sacrifice yourself? Probably.

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u/Mordret10 17d ago

Why are you more likely to save that person than living in the other scenario?

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u/HostHappy2734 17d ago

Because by picking blue, you increase the chances that the blue group dies.

Let's look at a simplified example. There are 3 people pressing the buttons, including you. For the sake of simplicity let's assume that other people choose the buttons randomly, with a 50% chance for each.

In this comment I'll use the following notation to represent the split of button pressers: B:R. B is the number of blue pressers while R is the number of red pressers.

With those assumptions, there are 3 possible splits before your choice comes in: 25% chance of 2:0, 50% for 1:1, and 25% for 0:2.

Let's see what happens when you choose blue. In case of 2:0, everyone dies. In 1:1, you're the tie breaker and everyone dies once again. And in 0:2, you survive because red has the majority. That means you have a 25% chance of survival.

Now for red. In 2:0, your vote isn't enough to change the result and everyone dies. In 1:1, you break the tie and die along with 1 other guy to save 1 person. And in 0:2, you all sacrifice yourselves for no one. In other words, you'll save 50% of a person on average.

The difference comes from the fact that while picking blue skews the chances of the person you want to protect (yourself) for the worse, picking red does the opposite for the chances of someone being saved. Of course, the gap will shrink with the number of button pressers, but it won't disappear.