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Can you solve the troll’s paradox riddle? - Dan Finkel

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1,301 Questions Answered

TEDEd Animation

Let’s Begin…

You and your brother have discovered another realm and set off exploring the new wonderful world. Along the way, you see a troll catching creatures in an enormous net. The troll agrees to release the creatures if you can come up with a statement that is both truth and false. Can you come up with the correct sentence and force the troll to release them? Dan Finkel shows how.

Additional Resources for you to Explore


How much more coercive can you get with coercive logic? Can you think of a way to get the troll to dance around or cluck like a chicken if it has to act according to the rules it set out? What are the limits of coercive logic?

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Meet The Creators

  • Educator Daniel Finkel
  • Director Igor Coric, Nemanja Petrovic
  • Narrator Addison Anderson
  • Producer Milica Lapcevic
  • Content Producer Gerta Xhelo
  • Editorial Producer Alex Rosenthal
  • Associate Producer Bethany Cutmore-Scott
  • Fact-Checker Brian Gutierrez

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