Cool magic trick: The Perpetual Puzzle


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Great, not I’m craving an infinite chocolate bar.


Not allowed to tell the solution, so I’m left dancing around it. At a few points, it was briefly obvious what was going on. Pay attention to the times he neatens up the layout.
This is actually a fairly well known illusion. Great presentation though.


Puzzles in this family were really popular in the 19th century, many due to Sam Loyd (whose Cylopedia is still available and a great read for puzzle fans).


Exactly! Whenever I see a puzzle like this, Sam Loyd is the first thing that comes to mind. Get Off The Earth was the first one I remember seeing/hearing about.


It is fine to dance around it.


It is intuitively obvious to the casual observer.

(What mathematicians say when they’re baffled.)


They forgot to print on pictures of dwarfs that increase in number.


This seemed familiar for some reason. :smiley: And it still hurts my brain.


If you know, please don’t reveal the secret

Memo to self: Don’t say he’s a witch.


I’ve seen other versions of the Freer style puzzle with a grid printed on it, which I thing makes it even more perplexing.


“The rectangle fits snugly in a black plastic frame”

Does it?


Just checked Martin Gardner’s Mathematics, Magic and Mystery, he traces these kinds of puzzles at least as far back as this one by William Hooper in 1794:
Here’s one of Gardner’s own creations, which is great because you can have young kids cut it out of graph paper for themselves then work out the mystery:
(Gardner calls these “Curry puzzles”, but I’ve heard mathematicians use the term “Fibonacci puzzles” because of how they work.)


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