'Einstein's Riddle' is said to have been invented by Albert Einstein as a boy. It is said that he claimed only 2% of the world's population would be able to solve it. This ingenious puzzle set has been based on Einstein's Riddle, but don't worry, because this version is much more solvable and has been broken down into 84 challenges with increasing levels of difficulty. This is how it works. In front of you is a row of houses. Each is home to a different person and in some cases, their pet. Combining the clues that you are given with logical deduction, your challenge each time is to work out who lives where. The concept is brilliant and the puzzles fantastic!