Pretend that you are unlucky enough to fall into a cave without a flashlight. However, you are lucky enough to have a bucket of glow-in-the-dark basketballs. Suddenly, you hear a snuffling sound. Is it a blood-thirsty bear, or merely your friends playing a practical joke on you?

To find out, you desperately toss the basketballs in the direction of the snuffling sound, and memorize where the basketballs hit. Thus, you rapidly figure out the following outline of the being in front of you:

Yikes! Since your basketballs are so big, when they bounce off the thing in front of you, all you can learn about its shape is that it is wide and tall.

Fortunately, you ALSO brought a bag of glow-in-the-dark tennis balls. You toss these in the direction of the snuffling, and are rewarded with the following image:

Hmm..... not much better. Tennis balls are still too big to figure out the shape of the object they hit. You only have a rough idea about the thing's outline.

Aha! What luck! Your bag of glow-in-the-dark marbles should do the trick! You toss these little balls at the being, and note that you can figure out a pretty clear image of the thing's shape. It seems to be big, hunched over, and have enormous claws. A bear!

Your last, but gleeful, thought is that you used the smallest possible probe to get the most information about your fate.

No bears were harmed in the making of this web page!