# I just don't understand
**URL:** https://boards.straightdope.com/t/i-just-dont-understand/670325
**Category:** Miscellaneous and Personal Stuff I Must Share
**Created:** [October 4, 2013, 3:42am UTC](https://boards.straightdope.com/t/i-just-dont-understand/670325 "2013-10-04T03:42:54Z")
**Posts on this page:** 10
**Page:** 1
### Author:  [@ducati](https://boards.straightdope.com/u/ducati)
#### Post date: [October 4, 2013, 3:42am UTC](https://boards.straightdope.com/t/i-just-dont-understand/670325/1 "2013-10-04T03:42:54Z")
[It’s a puzzle that I don’t understand.](http://tyleroakley.com/post/63045364380/dont-mind-me-while-i-stare-at-this-for-the-next-4?utm_campaign=SharedPost&utm_medium=Email&utm_source=TumblriOS)
How do they have 1 block left over, while still ending up with 4x6 rows?
What obvious thing am I missing?
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### Author:  [@Roderick\_Femm](https://boards.straightdope.com/u/Roderick_Femm)
#### Post date: [October 4, 2013, 4:04am UTC](https://boards.straightdope.com/t/i-just-dont-understand/670325/2 "2013-10-04T04:04:39Z")
Mouseover space
The final version is not a full 6 blocks tall, it’s just a little shorter all the way across, which adds up to the equivalent of one block total left over.
You have to look really carefully, and compare where the little partial blocks join. I can’t explain it any better than that.
Roddy
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### Author:  [@GuanoLad](https://boards.straightdope.com/u/GuanoLad)
#### Post date: [October 4, 2013, 5:57am UTC](https://boards.straightdope.com/t/i-just-dont-understand/670325/3 "2013-10-04T05:57:04Z")
It’s [this puzzle](https://en.wikipedia.org/wiki/Missing_square_puzzle) chocolatified. A subtle illusion of angles.
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### Author:  [@Senegoid](https://boards.straightdope.com/u/Senegoid)
#### Post date: [October 4, 2013, 7:28am UTC](https://boards.straightdope.com/t/i-just-dont-understand/670325/4 "2013-10-04T07:28:06Z")
There are many variations of this trick, some of them artistic and amusing. The great puzzlemeister [Sam Loyd](http://en.wikipedia.org/wiki/Sam_Loyd) had an interesting version called the “Get Off The Earth” puzzle.
It was like a circular slide rule, with a rectangular cardboard back piece, and a circular cardboard front piece, riveted at the center so you could rotate it. It had caricature pictures of several “Chinamen” on it, drawn with part of them on the back piece and part of them on the central disk. When you rotate the disk, the pieces of the pictures align differently, and one of the “Chinamen” disappears.
Discussions, with pictures of the thingy:
[http://www.jimloy.com/puzz/getoff.htm](http://www.jimloy.com/puzz/getoff.htm)
[http://britton.disted.camosun.bc.ca/jbgetoffearth.htm](http://britton.disted.camosun.bc.ca/jbgetoffearth.htm) (with animated GIF!)
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### Author:  [@Alan\_Smithee](https://boards.straightdope.com/u/Alan_Smithee)
#### Post date: [October 4, 2013, 7:34am UTC](https://boards.straightdope.com/t/i-just-dont-understand/670325/5 "2013-10-04T07:34:55Z")
I never would have thought of doing it with chocolate. Brilliant, because it’s something everyone is familiar with and that comes with nice clear rectilinear lines. And it tantalizes with the idea of an infinite source of chocolate!
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### Author:  [@sailor](https://boards.straightdope.com/u/sailor)
#### Post date: [October 4, 2013, 7:38am UTC](https://boards.straightdope.com/t/i-just-dont-understand/670325/6 "2013-10-04T07:38:31Z")
> [@GuanoLad](#):
>
> It’s [this puzzle](https://en.wikipedia.org/wiki/Missing_square_puzzle) chocolatified. A subtle illusion of angles.
No, it is very different.
The “missing square puzzle” is based on the fact that two (red and blue) triangles have different slope angles (2/5 and 3/8) but close enough to be overlooked without looking closely.
This chocolate puzzle is just cutting a (constant slope) diagonal and shifting everything sideways so where you had 1 x 1 squares now you have 4 “squares” with lesser height. It would be very obvious if done with exactly marked paper but with chocolate the squares are not so clearly delimited and admit more fudge. _\__
This is the same as the [vanishing leprechaun](http://britton.disted.camosun.bc.ca/jblep1.htm) and the old trick of cutting X money bills and getting X+1 money bills (which are imperceptibly smaller than the originals). This is the reason the money bills have the same serial number printed twice, to prevent this trick.
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### Author:  [@TruCelt](https://boards.straightdope.com/u/TruCelt)
#### Post date: [October 6, 2013, 7:05pm UTC](https://boards.straightdope.com/t/i-just-dont-understand/670325/7 "2013-10-06T19:05:55Z")
OK, so I totally got the OP’s one right away. (The remnants of the diagonally sliced boxes make up a little less than one block, which is then removed. The line through the sliced ones tricks us into missing the fact that they are now shorter.)
But even after reading the solution to the leprechaun one, I’m still not getting it. If you count the heads, a new one has definitely shown up.
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### Author:  [@sailor](https://boards.straightdope.com/u/sailor)
#### Post date: [October 6, 2013, 7:18pm UTC](https://boards.straightdope.com/t/i-just-dont-understand/670325/8 "2013-10-06T19:18:22Z")
> [@TruCelt](#):
>
> But even after reading the solution to the leprechaun one, I’m still not getting it. If you count the heads, a new one has definitely shown up.
And if you count the bodies there is one more. If you read the entire page at the bottom is a link to the explanation: [http://britton.disted.camosun.bc.ca/jblep3.htm](http://britton.disted.camosun.bc.ca/jblep3.htm)
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### Author:  [@Chronos](https://boards.straightdope.com/u/Chronos)
#### Post date: [October 6, 2013, 7:19pm UTC](https://boards.straightdope.com/t/i-just-dont-understand/670325/9 "2013-10-06T19:19:38Z")
None of the 15 has a whole head. The heads are a bit smaller after than they were before. Try counting noses, instead: Leprechaun 11/15 is missing a nose.
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### Author:  [@sailor](https://boards.straightdope.com/u/sailor)
#### Post date: [October 7, 2013, 12:33am UTC](https://boards.straightdope.com/t/i-just-dont-understand/670325/10 "2013-10-07T00:33:14Z")
Get off the Earth: [http://britton.disted.camosun.bc.ca/jbgetoffearth.htm](http://britton.disted.camosun.bc.ca/jbgetoffearth.htm)