Complex numbers as 'cyclic numbers' is not widely understood. What is understood is how they fit into the arithmetic 'hierarchy': how the real numbers embed int

Complex numbers as 'cyclic numbers' is not widely understood. What is understood is how they fit into the arithmetic 'hierarchy': how the real numbers embed into the real axis, and how the operational rules for addition and multiplication work. However SICP also asks us to implement the polar form of C to illustrate multiple representations of the same data type, so I have to admit that part might require some additional explanation for many students.