You’re given two indistinguishable envelopes, each containing money. One envelope contains twice as much money as the other. You may pick one envelope and keep whatever amount it contains. However, after picking, but before opening the envelope, you’re given the chance to switch your envelope with the other one. The question is: Should you switch?…
On a remote island live 100 people with blue eyes and 100 people with brown eyes. Every person on the island is highly logical but is not aware that there are exactly 100 people with blue eyes and exactly 100 with brown eyes. However, nobody knows their own eye colour; they can only see the…
This one is super tough, so strap in! There are 100 prisoners in solitary cells. There’s a central living room with one light bulb, which is initially off. No prisoner can see the light bulb from his or her own cell. Every day, the warden picks a prisoner equally at random and takes them out…
In the dead of night, four people need to cross a rickety bridge. Unfortunately, they have only one torch and the bridge is too dangerous to cross without one. The bridge is only strong enough to support two people at a time. Not all people take the same time to cross the bridge: Person A…
A king had received a gift of 100 bottles of wine but suspected one had been poisoned. The king placed 100 wine bottles on the table, 99 of which contained normal wine and one which contained poison. Even a sip of the poisoned wine was enough to kill. The poison was indetectable, meaning it wouldn’t…
Imagine a round manhole (a circular hole cover) and a square manhole. Both of them have the same area, and both of them are designed such that the cover should not fall into the hole regardless of how you orient it. Now, the round manhole cover won’t fall into the round hole because the diameter…
