Einstein's Riddle (Zebra Puzzle) Explained

Short answer: Einstein's riddle, also called the zebra puzzle, is a logic puzzle where five people each have one house color, nationality, drink, pet and hobby. A list of clues lets you work out every pairing, and there is exactly one answer.

The rules

Each person has exactly one item from each category.
No two people share an item in the same category.
Every clue is true. You combine them until only one arrangement fits.

Why it feels hard

The classic version has 5 people and 5 categories, so there are 25 ways for each category pair to match. Most clues only rule something out, and the important deductions come from combining two or three clues. Keeping that in your head is what makes it famous.

How to start

Draw a grid. One block for each pair of categories, with people as rows. A grid turns memory work into marking.
Mark the fixed clues. "The Norwegian lives in the first house" style clues give a ✓ straight away.
Mark every "not". Negative clues become ✗ marks.
Look for the last empty cell in each row and column.
Copy facts across blocks. If A goes with B and B goes with C, A goes with C.

Start smaller

You do not need the full 5 × 5 version to enjoy the idea. Grids with 3 categories of 4 items take a few minutes and teach the same moves; 4 categories of 5 items is close to the classic challenge.

How Inferlo helps

Inferlo is an Einstein-style logic grid game with four levels, from Easy (3 categories × 4) to Expert (4 × 5). Every level is open from the start, every puzzle has exactly one answer, and a new daily grid arrives each day.

FAQ

Did Einstein really write the riddle?

There is no evidence that he did. The puzzle became famous as "Einstein's riddle" in the 1960s, and the original version appeared in Life International magazine in 1962.

Why is it called the zebra puzzle?

Because the classic version ends by asking "Who owns the zebra?" and "Who drinks water?".

Is the classic puzzle too hard for beginners?

The classic version has 5 houses and 5 categories, which is a lot to hold in your head. Smaller grids with 3 or 4 categories teach the same techniques in a few minutes.

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