>>>The parenthesis depends on how many stones you weigh :).
>>
>>Wouldn't that depend on the size of the stones? If you use those ones that you can sit on in the park, then I weigh less than 1, but if you use the ones in my garden, then I probably weigh as much as a couple hundred of them. Never mind the ones that get into my shoe.
>
>Some time in the sixties I heard a joke that in the US they've invented a plastic stone. Smaller than a marble. Purpose: put it in your shoe, and it hurts the same as the natural stone.

I've come to the conclusion that the sole of the foot is the most sensitive surface on the human body. If I get a grain of kitty litter in my shoe (which happens far too often), it feels like a rock. A bit of road salt, and I'm just about crippled.