The Ship of Theseus, Schrödinger’s Cat, Prisoner’s Dilemma, and The Ones Who Walk Away from Omelas are my favorite thought and ethic experiments that are out there. We all know at least one thought experiment, most likely the Trolley Problem. In this problem you are an onlooker watching a rough trolley run down the tracks and it will hit five people. You have the option to divert the trolley and kill only one person instead, either way someone dies. The question is this, will you sacrifice the one to save the five?

I love to bring thought experiments into conversions as it reveals a lot of how someone thinks and what they value. It’s also just really fun to watch people question their entire lives. In fact The Ones Who Walk Away from Omelas really tells you what someone values. In the City of Omelas everyone is happy and prosperous but all that happiness depends on the eternal suffering of a child. No one can comfort the child in any way or the happiness of the rest of the town goes away. Everyone in town knows that the child exists. Do you walk away from the Omelas and eternal happiness or do you comfort the child and lose eternal happiness or maybe even just keep living like you always have?

The Ship of Theseus or Theseus Paradox is about a boat. Unlike the suffering of the child this one is less dark. So in this one there’s a ship. Over time let’s say a board goes moldy so you replace that board. Is it still the same ship? I mean it looks the same, but it wasn’t part of the beginning ship. Then as time goes on and on you have to keep replacing things on the ship until there is only one board left from the beginning of the ship. Asking again, is it the same ship? The ship looks the same but is it the same? Finally, you have to replace that last board with a new one. Is the ship still the same ship? If not, when did the ship become a different ship if it’s not the same one as in the beginning?

Now the next one has more to do with trust and does have a correct answer in mathematical terms. The Prisoner’s Dilemma. You rob a bank with an accomplice and the police catch you but still need a confession. Keep in mind you care more about your own well-being than your accomplices. The police put both of you in different rooms and make you and accomplice the same offer. “You may choose to confess or remain silent. If you confess and your accomplice remains silent I will drop all charges against you and use your testimony to ensure that your accomplice does serious time. Likewise, if your accomplice confesses while you remain silent, they will go free while you do the time. If you both confess I get two convictions, but I’ll see to it that you both get early parole. If you both remain silent, I’ll have to settle for token sentences on firearms possession charges. If you wish to confess, you must leave a note with the jailer before my return tomorrow morning.” What do you do? If you are the only one to confess you go free but if both of you confess you get parole. If you remain silent and the accomplice confesses you get the sentence but if neither one of you talks you both get the sentence. You have no way of knowing what your accomplice is thinking. The ‘answer’ to the problem is to confess, at least mathematically. It’s the only way to ensure that you may get out early or serve no time at all.

Saving my favorite one for last, we have Schrӧdinger’s Cat. This one goes back to being dark. A cat is in a box with the lid on and there is no way to see inside the box. Inside the box along with the cat is some radioactive material, a hammer, and a Geiger counter. If the Geiger counter detects any sort of decay from the radioactive material it will drop the hammer on the flask of poison killing the cat. But if the Geiger counter doesn’t detect anything the cat continues to live. You can’t see inside the box so you have no clue what happened. So is the cat alive or dead while in the box?

Bringing up any of these thought experiments at any social gathering is a guaranteed way to get odd glances cast at you and get talked about for a while. Especially if you play Devil’s advocate. Any one of these is a great conversation and these are just my favorite. A simple Google search will reveal more thought experiments to leave your friends reeling.