Full Idea
One approaches the natural numbers in terms of either their ordinality (Peano), or cardinality (set theory).
Gist of Idea
Natural numbers are seen in terms of either their ordinality (Peano), or cardinality (set theory)
Source
José A. Benardete (Metaphysics: the logical approach [1989], Ch.17)
Book Reference
Benardete,José A.: 'Metaphysics: The Logical Approach' [OUP 1989], p.130