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One hundred green-eyed logicians have been imprisoned on an island by a mad dictator. Their only hope for freedom lies in the answer to one famously difficult logic puzzle. Can you solve it? Alex Gendler walks us through this green-eyed riddle.
Lesson by Alex Gendler, animation by Artrake Studio.
0:00 Our goal 0:11 The grid sections 0:51 The clues point to certain squares 1:41 Relevant vs. irrelevant information 3:20 Use sections to help you with other sections How to solve multiple-section logic grid puzzles, […]
Logic grid puzzle method that kids can understand! Students SEE the Post-It manipulatives, HEAR clear narration, and TRANSFER their new knowledge to another format. Chapters: 0:00 Our goal 0:20 The clues 0:31 The grid 0:43 […]
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I might be taking this too seriously, but technically, if they’re all perfectly logical, then none of them learn anything new on day one. Noone seriously thought anyone else thought there could be just one person with green eyes. So the puzzle solution relies on people believing others gained information that should have already known. I feel like this breaks with the notion of perfectly logical.
However, I think it can still be salvaged. If there exists an algorithm that minimizes the amount of time green eyed people stay on the island, then it is logical that everyone would follow it. So, in order for you to convince me that everyone leaves on day 100, you’d need to show me that there exists no better algorithm where they leave earlier than day 100. In other words, you have to prove the algorithm to be optimal.
what abour all of you have a green eyes
couldnt you say “you all have the same eye color”?
I know this video is over a decade old but the solution I came up with was to say “You, personally, can see plainly that everyone around you has green eyes”. It would be a bit easier to follow but it’s about the same as saying “At least 99 of you have green eyes”
So they approach the guards and if they have green eyes they’re let go…
And the condition of them being freed is to have green eyes…the guards don’t asks for them to answer any question… doesn’t give them a reason why they cannot leave nor why they’re held there. They knew they have green eyes, they’ve seen each other once a day…
That’s the condition they’re held there and that’s the condition they can leave.
Only at night they can ask to leave… interesting…