Puzzles & Quizzes

The Crocodile Paradox Is an Unsolvable Dilemma That Dates Back to Ancient Greece

Paradoxes are fun for your brain to chew on for a bit, until they grow furiously frustrating. These statements, despite sounding simple, are self-contradictory or logically impossible: basically intellectual torture fuel. One such example is the crocodile paradox — a logic problem that was first discussed by ancient Greeks. And after all this time, that sucker is still unsolvable.

Related Video: 10 Mind-Bending Paradoxes

Between a Croc and a Hard Place

The crocodile paradox (or dilemma, whichever you want to call it) goes like this: A crocodile has captured a little boy. Being the reasonable crocodile that he is, the croc promises the little boy's father that he will release the kid only if the father can predict what the crocodile will do next. The father of the boy says, "You will not give my son back." Now the croc is in a bind. If the father was correct in his statement, the croc keeps the kid. But if the croc keeps the kid, the croc is not keeping his promise to return the boy. But once the croc returns the boy, the father's prediction is no longer correct. What should the crocodile do?

You can scroll around this page and Google search as much as you want, but you won't be able to dig up the correct answer. That's what makes this thing a paradox. Fun, right?


To quote the philosopher Søren Kierkegaard, "The thinker without a paradox is like a lover without feeling." Thinkers dating back to ancient Greece have toyed with paradoxes like the crocodile dilemma. (The earliest of these contradictory mind games was likely the Epimenides paradox, which dates to the 6th century B.C.E.)

The croc problem is an old one (it was also referenced by German philosopher Carl von Prantl in 1855), and it involves some screwy logic that's at play in other well-known paradoxes. Perhaps you've heard of the self-referential conundrum that is the liar's paradox. Similarly, the unexpected hanging paradox is also in this family of problems. Have fun, and good luck.

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Dive into the realm of formal logic with "Unified Logic: How to Divide by Zero, Solve the Liar's Paradox, and Understand the Nature of Truth" by Jesse Bollinger. We handpick reading recommendations we think you may like. If you choose to make a purchase, Curiosity will get a share of the sale.

Written by Joanie Faletto September 16, 2017

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