Ah, thank you. It does actually make some sense, having looked into it some more now (: It looks like the approach of defining ℤ in terms of ℕ is much more ted

Ah, thank you. It does actually make some sense, having looked into it some more now (: It looks like the approach of defining ℤ in terms of ℕ is much more tedious to deal with overall, so can see the advantages.