Want a daily email of lesson plans that span all subjects and age groups?
Learn more

Can you solve the famously difficult green-eyed logic puzzle? - Alex Gendler

  • 11,816,947 Views
  • 30,399 Questions Answered
  • TEDEd Animation

Let’s Begin…

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.


Customize This Lesson

197

Create and share a new lesson based on this one.

About TED-Ed Animations

TED-Ed Animations feature the words and ideas of educators brought to life by professional animators. Are you an educator or animator interested in creating a TED-Ed Animation? Nominate yourself here »

Meet The Creators

  • Educator Alex Gendler
  • Director Outis
  • Narrator Addison Anderson
Additional Resources for you to Explore
See a couple of different formulations of the puzzle here, here, and here, along with discussions that show why the precise details of the puzzle setup make a huge difference. Read more about common knowledge at the Stanford Encyclopedia of Philosophy, or check out David Lewis’s original book: Convention: A Philosophical Study on the subject. To see how the concept can apply to economics and game theory, take a look at the work of Robert Aumann, Shyam Sunder, and John Allen Paulos.

Customize This Lesson

Create and share a new lesson based on this one.

About TED-Ed Animations

TED-Ed Animations feature the words and ideas of educators brought to life by professional animators. Are you an educator or animator interested in creating a TED-Ed Animation? Nominate yourself here »

Meet The Creators

  • Educator Alex Gendler
  • Director Outis
  • Narrator Addison Anderson

More from The Big Questions