George wrote:

Is a circle a wheel?


It depends if they roll it to go from A to B.

A circle only exits in a flat plane with no depth. The calendar had a
depth to it.

If depth is not important, then the question is "when does a circle
become a cylinder?" For instance a circle of zero depth with a diamerter
of four feet, is now stretched out to a depth of eight feet. Clearly
this is now a cylinder. It got to be a cylinder by passing through the
wheel stage.

Now lets all go to ebay and buy pen blanks.