The saying refers to the roundness of the wheel, which has not been re-invented for thousands of years. Changing the material are optimization which deserve muc

The saying refers to the roundness of the wheel, which has not been re-invented for thousands of years. Changing the material are optimization which deserve much credit but aren't new inventions on the definition of the wheel. Wikipedia defines a wheel as "A wheel is a device that allows heavy objects to be moved easily through rotating on an axle through its center"