Can You Solve Einstein's Riddle?

Are you a braniac or a smarty-pants? Is Einstein your hero? Is the Riddler your favorite villain? Were Gollum’s riddles one of your favorite parts of “Lord of the Rings”? Well, then riddle me this. 

“Einstein’s Riddle” is a complicated test of logic that has alternately stumped and pumped intellectuals and would-be enigmatologists for at least a century. Supposedly only 2% of the population are able to solve it.^<1>

Though the percentage of people who can solve the puzzle is likely much larger, it does take a fair amount of patience and determination to follow the chain of reasoning through to the end. If you’re easily distracted, you probably won’t have much luck. Unless you’re a super-genius like Einstein. 

Who Wrote the Riddle?

According to popular legend, young Albert came up with “Einstein’s Riddle” sometime in the early 1900’s – no one really knows the exact year. And there’s no proof that Einstein actually even wrote it. Some claim author and fellow logician Lewis Carrol created it. Carroll is most famous for penning Alice’s Adventures in Wonderland, and for those who attempt to solve the riddle unprepared, the process could seem like a twisting, turning mental maze much like Alice’s Wonderland.

While the source hasn’t technically been verified, the brain puzzle is still officially recognized as “Einstein’s Riddle.” Also called the “Zebra Puzzle,” the riddle has taken on many incarnations.

An early published version appeared in Life magazine’s December 17, 1962 issue. Life then gave the solution along with the names of hundreds of international solvers in the March 25, 1963 issue.

The specifics may change, but the puzzle always contains five categories with five different options for each.a

The Rules

Four stipulations outline the puzzle:

1. There are five houses. Each house is a different color
2. People of different nationalities live in each of the five houses.
3. All five people smoke a certain brand of cigar, drink a specific beverage and have a different type of pet.
4. None of the five people smoke the same brand of cigar, drink the same beverage or own the same type of pet.

Every thing in Einstein's Riddle is one of a kind.

The Clues

Fifteen clues accompany the rules to give hopeful solvers a chance. These are considered the original ones:^<2>

1. A Brit lives in the red house.
2. The Swede keeps dogs as pets.
3. The Dane drinks tea.
4. The green house is to the immediate left of the white house.
5. The green house's owner drinks coffee.
6. The owner who smokes Pall Mall rears birds.
7. The person in the yellow house smokes Dunhill.
8. The one in the center house drinks milk.
9. A Norwegian lives in the first house.
10. The person who smokes Blends lives next to the one who keeps cats.
11. The owner of the the horse lives next to the one who smokes Dunhill.
12. The one who smokes Bluemasters drinks beer.
13. The German smokes Prince.
14. The Norwegian lives next to the blue house.
15. The owner who smokes Blends lives next to the one who drinks water.

Tip: In clue #4, the green house is on your left of the white house.

The Question

The question is - Who owns the fish?

Solving Einstein’s Riddle

People use various methods to solve the riddle, and any way you choose is the right way if it works. There’s really no wrong way as long as you come up with the correct answer.

That said, here are some of the more popular methods people use to find the fish.

The Grid

One way to solve the riddle is to make a six-square grid. Put the houses across the top, numbering them one through five. Put the other categories down the side, then fill in what you already know from the clues – and not necessarily in order.

For example, clue number 9 says the Norwegian lives in the first house, and clue 14 tells us the Norwegian lives next to the blue house. Since there’s only one other house next to the first one, house number two must be blue.

Continue filling in boxes with the rest of the clues.

When you’ve filled in as many clues as you can, you’ll have to start putting multiple options together in the remaining empty boxes. Since there can’t be two of the same thing, you’ll be able to eliminate options step by step.

You can organize the grid any way you like. If you solve the puzzle correctly you’ll still get the same answer.

Left to Right

Number the boxes across the top 1 - 5. These will be the houses. Number 1 is on the far left, while number 2 is on the far right. Looking at the clues, you’ll see that the Norwegian lives in the first house. The blue house is next to the Norwegian, making number 2 the blue one. Now you’ve got a solid start.

Right to Left

Number the boxes from right to left, with 1 at the far right and 5 at the far left. The Norwegian still lives in house 1, and the house next to it is still blue. Same thing, but it might be easier to solve this way for lefties or artistic types that are more right-brained.

Trial and Error^<3>

Instead of making a grid, make a list. Since there can only be one of everything, you can find the fish by elimination.

First, make a list of all the variants. In this case it will be house colors, beverage type, cigar brand, and pet.

Next, find the colors of all the houses. We know house 2 is blue, so we can cross that off the list. We know house 1 can’t be green or white, because they have to be next to each other. The English person lives in the red house. Therefore, the first house has to be yellow.

Now that you know the color of the 1st house is yellow, you also know the Norwegian lives there, and Dunhills are smoked there. Cross those off the list. According to clue 11, the horse is in the blue house.

Now you can start pairing things together or placing them singly to get a better idea of what goes where.

For instance, Bluemasters and beer go together (clue 12). The green house has coffee and is left of the white house (clues 4 & 5). Pall Mall and birds go together (clue 6).

So far, we’ve eliminated three brands of cigarettes, and from the clues we know the Norwegian in the first, yellow house doesn’t drink beer, milk, tea, or coffee, so they must drink water. Cross off water, and you know the owner of the blue house smokes Blends (15), so you can cross that off too.

So who lives in the blue house? Not the Norwegian. The Brit lives in the red house. The German smokes Prince, not Blends. And since the horse is already in the blue house, it can't be the Swede - who has dogs. It has to be the Dane! And the Dane drinks tea. Now you have the blue house filled up and those options are all closed.

Keep eliminating things through trial and error, and you’ll eventually find the fish.

Solving riddles strengthens the brain.

But, Why Bother?

Sure riddles are fun - or frustrating - but what is the significance of a riddle anyway? I mean, why bother?

For one thing, solving puzzles like this one exercises your brain, keeping it sharp and responsive. Your brain needs activity to stay in good shape just like your body does. Playing brain games has been shown to reduce the likelihood of experiencing age-related neurological problems like Alzheimer’s and dementias.^<4>

Riddles also require the use of both right and left brain hemispheres, blending creative thought with logical solutions. Unlike a mere math equation, word-based riddles make your brain think in terms beyond numerical outcomes.

When you play with Einstein’s Riddle, your brain “sees” the tactile yet imaginary objects you’re working with. Your brain visualizes something like a Norwegian sitting in a chair in a yellow house, petting a cat and drinking a glass of water.

Using imagination enhances creativity at the same time logical thought stimulates critical thinking centers in the left brain. Activating right and left brain together can create new neural connections and strengthen existing ones between the two.

Aawww, they’re bonding!  

Two brain hemispheres are better than one.

The Answer

Did you wait until the end of this article to discover the actual answer? Maybe you gave it a go yourself. If so, congratulations on your patience and persistence! If you skipped right to the end, well, here you go.

Drumroll please……

The German has the fish.

Modern Versions

Because this is the 21st century, some adaptations have been made to the original content. Cigars are now often replaced with cars. Children’s versions substitute snacks for the cigars and exchange beer for juice.

Feel free to make up your own categories and other content. Just be sure to keep the heart of the rules and the soul of the clues the same.

What interesting versions can you come up with?