What gets sharper the more you use it, yet stays completely immobile while doing its job?
A whetstone or sharpening stone
A whetstone is used to sharpen blades. As knives rub against it, the stone's surface wears down to become finer and more effective, while the stone itself remains entirely stationary on the table.
About this riddle
Logic riddles give you a few facts and ask what must be true. List what you know, cross out what cannot be, and see what is left.
Difficulty: Easy. More like this: Logic riddles with answers or try Einstein's Logic Grid for a different kind of puzzle.
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