Sorites paradox

The sorites paradox is a puzzle that comes up when you try to figure out when a pile of objects stops being a "pile". Imagine you have a pile of 10 stones. If you take away one stone, it's still obviously a pile of stones. Now what if you take away one more stone--is it still a pile? Well, yeah, it still looks like a pile. What about if you take away one more stone? It still looks like a pile, so it probably still is a pile. But what if you keep going and take away one more stone every time? After a while, you'll take away so many stones that the pile will look like nothing at all. So is the pile still a pile, or isn't it? That's the sorites paradox!