Primitive Domains
What about natural number subtraction?
What if we have subtract(three,five)?
Using the algebra we can construct expressions that represent members of Nat e.g. plus(times(three, two), minus (one, zero)) which we determine (through simplification) represents the constant named seven.
What about natural number division?
What if we have division by zero?
We need to add an extra element to Nat called error. What impact has this on the other operations? E.g. Plus(three, error).