Einstein’s so-called enigma —the one that, supposedly, only 2% of the population can solve— is surrounded by other enigmas.
There are no reliable sources, no scientific studies, nothing that can prove whether it was really Einstein who proposed the riddle and that 98% of humanity is unable to solve it.
What is certain is that the enigma and all its variations spread quickly across the internet and the media. The problem was even mentioned by Stanford University, in the United States.
What does the riddle say?
The question statement provides 15 clues about a street where there are five houses. Each house is a different color, each resident has a nationality, a pet, a drink and a brand of cigarette — all different.
The objective is to find out who owns the fish, knowing that:
Or myth two 2%
I need to open a parenthesis in this article and I take this opportunity to encourage you to stop reading and try to solve the riddle: it is not true that only 2% of humanity can reach the solution.
With this information and if you feel it is appropriate, put this article aside for a while, grab a pencil and paper and try to find the answer.
That said, we continue towards the solution. There is a graphical way to solve the puzzle… using PowerPoint!
If you have already started to solve the problem, you may have imagined that you need to fill in a table, using the clues until you finally discover who owns the fish. This is a good way. But instead of a board, let me call it a board.
Let’s first insert rectangles into a blank PowerPoint sheet.
Then we place all available “cards”. The order, for now, does not matter — we will simply include them as they appear.
We will then have something like this (attention: this is not the solution; I recommend copying the blank table onto another PowerPoint slide, to fill in later):
Now comes the crux of the matter.
Let’s use PowerPoint’s group function to intertwine the cards with the clues we already have.
When two figures are grouped together, they merge and move as if they were one. I use the Control key to select both.
So, we group the cells knowing that clue 1 says: “the British lives in the red house” and we separate these cards from the board.
We continue with clues 2 and 3, moving the cards to keep them in the corresponding row and column (note that the bring to front option in PowerPoint can also help). The Swede has a dog and the Dane drinks tea.
Clue 4 —”the Norwegian lives in the first house”— is even easier. We can incorporate it directly into the final solution board.
Let’s repeat the group operation with tracks 5, 6, 7, 8 and 9.
Clue 10 —”the resident of the central house drinks milk”— passes directly to the final board.
With clue 11 (“who smokes Blends lives next to a cat”), we need to be more careful: “cat” goes next to “Blends”, but which side?
We need to leave both options available (left or right) on the board.
And, so as not to forget that the two options are the same combination, we left them with a yellow background.
The same goes for lane 12 (the horse next to Dunhill). The fact that Dunhill is already grouped with the yellow square is not a problem — the cigarette is returned to the board to maintain distances.
At this point, it doesn’t take much effort to include clue 13, which indicates that Bluemaster goes with the beer.
But you need to pay attention to clue 14: “those who smoke Blends live next to those who drink water”. With “Blends”, we already had two options on the yellow board. Whoever drinks water can be on one side or the other and, therefore, four possibilities arise.
And, finally, comes clue 15 —”the Norwegian lives next to the blue house”. This passes directly to the final board.
After analyzing all the clues (the fish, by the way, doesn’t appear in any of them), we started playing to see where each one fits in.
To do this, we bring the final board to the first slide (or the other way around, I won’t be the one to tell you how to play).
Now, let’s try. First, let’s include words that have only one option. For example, the groups “Pall Mall – birds” and “British – red” fit in multiple locations, but “green – white – coffee” only fits in one.
Which leaves us with just one option for the “British – red” group. Let’s put!
The empty space in the color line can only be “yellow”, which had two options for inclusion on the board. Since there can be nothing to the left, it will be the top option.
From now on, everything gets complicated, especially for those who tried to solve it with pencil and paper. This is because all groups have several options.
Our only alternative is the well-known “goalkeeper’s chance” — that is, making assumptions, as if we were solving a sudoku puzzle. Let’s suppose, for example, that the group “beer – Bluemaster” enters the blue box.
This leaves us with only the “Danish – tea” options in the white house and “German – coffee” in the green one.
But pay attention! Now, we have nowhere to put the “Swede – dog” group. Therefore, the hypothesis “beer – Bluemaster” in the blue house is wrong. She must go to the White House. Everything needs to be undone…
Now yes. We can start filling in again.
And pay attention! Habemus owner of the fish! Bingo!
After all, who owns the fish?
The conclusion is that the owner of the fish is a German who lives in a green house, drinks coffee and smokes Prince. Alive!
I hope it was interesting and I encourage you to challenge your friends to try to solve the problem.
Receive an enigmatic hug!
This article was originally published on the academic news website The Conversation and republished under a Creative Commons license. Read here original version in Spanish.