There’s nothing like a good riddle to stimulate your mind and give you an excuse to channel your inner Sherlock Holmes. Sure, the thrill of solving puzzles may not give you the adrenaline rush of a skydive, but regularly doing logic and jigsaw puzzles can keep your brain young as you age. And they’re just a lot of fun.
Rumour has it that Albert Einstein made up an impossibly difficult riddle when he was just a kid, and he estimated that only two percent of the people who tried to solve it would successfully do so. There's no evidence to back up that apocryphal claim, but the rumour earned the popular logic puzzle the nickname "Einstein's Riddle."
Regardless of who actually came up with the riddle, it's not terribly difficult to solve — if you have the patience to think it through. There are no tricks to this riddle. Like Sherlock Holmes, all you need is logic and deduction. While there isn’t any solid evidence to confirm that Einstein created it—and somehow prophesied the exact number of people to get it right—it’s still a mind-bending puzzle. Doing some of these weird brain puzzles can make you smarter, too.
Here's the riddle:
Five houses painted five different colours stand in a row. One person of a different nationality lives in each house. The five home owners all drink some type of beverage, smoke a certain cigar brand, and have a certain kind of pet. But none of the owners drink the same beverage, smoke the same type of cigar, or have the same pet.
And here are the clues:
1. The Brit lives in the red house.
2. The Swede keeps dogs as pets.
3. The Dane drinks tea.
4. The green house is on 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 owner of the yellow house smokes Dunhill.
8. The owner living in the center house drinks milk.
9. The Norwegian lives in the first house.
10. The owner who smokes Blends lives next to the one who keeps cats.
11. The owner who keeps the horse lives next to the one who smokes Dunhill.
12. The owner 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.
The question is: Who owns the fish?
With so many variables (house number, house colour, nationality, drink, cigar, and pet), solving the puzzle gets complicated fast.
Eventually you'll fill in all the squares and figure out that (drum roll...) the German in house number four owns the fish.
Whenever you have a complicated set of states you are confused by, draw a basic truth table. Or however you want to represent the problem. Breaking it down into smaller and smaller pieces will allow you to solve almost anything.
If you’re a regular puzzle solver, you may need to amp up the complexity to keep yourself challenged. “When someone becomes an inveterate solver of a puzzle, they need more complexity or challenge because the expertise gained renders the basic puzzle uninteresting,” says Marcel Danesi, a professor of semiotics and anthropology at the University of Toronto’s Victoria College and author of The Total Brain Workout: 450 Puzzles to Sharpen Your Mind, Improve Your Memory, and Keep Your Brain Fit. “There is no more difficult puzzle, just more complex.” Scroll on for hard jigsaw puzzles that demand everything you’ve got. Here are some of the most demanding jigsaw puzzles around: