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The famous Sleeping Beauty problem has divided probability theorists, decision theorists and philosophers for over 15 years. Puzzle columnist Pradeep Mutalik claims to have discovered the source of confusion.

For four game show variations of the hat puzzle, four clever ways to earn a better payoff than you might expect.

In three new variations of a famous logic puzzle, what are the best strategies for guessing the color of the hat on your head?

Assigning elements from a large collection to one of two categories can yield almost “magical” predictions about highly complicated problems without actually solving them.

In a geometrically designed social club, how do dancing, triangles and hexagons mix?

The solution to this month’s puzzle gets to the bottom of the famously ambiguous Sleeping Beauty probability problem.

Like a visually ambiguous Necker cube, the famous Sleeping Beauty problem can be perceived in two seemingly valid ways.

The solution to this month’s puzzle explains how to design a Sudoku square to figure out the likes and dislikes of four or eight finicky friends.

For this month’s puzzle, design a Sudoku square to figure out the likes and dislikes of four finicky friends.