One day a farmer called up an engineer, a physicist and a mathematician and asked them to fence off the largest possible area with the least amount of fence.
The engineer made the fence in a circle and proclaimed that he had the most efficient design.
The physicist made a long, straight line and proclaimed, ‘We can assume the length is infinite.’ He pointed out that fencing off half of the earth was certainly the most efficient way to do it.
The mathematician built a tiny fence around himself and said ‘I declare myself to be on the outside.’