When he was in primary school, the teacher said:
"Everything has some size. In mathematics, they say a line has
zero width, but I don't believe it. If I draw a line with this
chalk, it has some width. If it didn't have any width, it wouldn't
exist."
At this point Ben pipes up:
"I can draw something with zero width."
The teacher said:
"Show me."
So Ben went up to the chalkboard and ......
So the puzzle is: What happened next?
The answers I'm looking for might take the form:
-- If you think it is not possible to draw something with zero
width, explain why not.
-- If you think it is possible, explain the best way to go about it.