You don’t need to be well-versed in quantum physics or even complex math to solve Albert Einstein’s famous house riddle. All it takes to tackle the problem below is logic—and if that isn’t enough for you, scroll down to the answer at the end of the article.
According to Popular Mechanics, the riddle goes like this: There are five houses lined up next to each other along a street. Each house is a different color, and each homeowner is of a different nationality, drinks a different beverage, smokes a different brand of cigar, and owns a different pet.
If these variables can never repeat from house to house, which homeowner has a pet fish? You should be able to figure out the answer based on these 15 clues:
1. The Englishman lives in the house with red walls.
2. The Swede keeps dogs.
3. The Dane drinks tea.
4. The house with green walls is just to the left of the house with white walls.
5. The owner of the house with green walls drinks coffee.
6. The man who smokes Pall Mall keeps birds.
7. The owner of the house with yellow walls smokes Dunhills.
8. The man in the center house drinks milk.
9. The Norwegian lives in the first house.
10. The Blend smoker has a neighbor who keeps cats.
11. The man who smokes Blue Masters drinks beer.
12. The man who keeps horses lives next to the Dunhill smoker.
13. The German smokes Prince.
14. The Norwegian lives next to the house with blue walls.
15. The Blend smoker has a neighbor who drinks water.
The popular lore of the riddle traces it back to Einstein’s teaching days. According to the story, the scientist gave the riddle to students to discourage them from picking him as their academic advisor, though this is likely just a legend. Another dubious element has been added to the riddle’s story since it hit the internet: Allegedly only 2 percent of the world’s population can solve it.
Whether that figure is true or not, thinking through the problem takes some real brain power. You can check out the solution in the video below.
This story originally ran in 2021; it has been updated for 2023.