Full Idea
Frege's account of the ancestral has made it possible, in effect, to define the natural numbers as entities for which induction holds.
Gist of Idea
It may be possible to define induction in terms of the ancestral relation
Source
report of Gottlob Frege (Begriffsschrift [1879]) by Crispin Wright - Frege's Concept of Numbers as Objects 4.xix
Book Reference
Wright,Crispin: 'Frege's Conception of Numbers' [Scots Philosophical Monographs 1983], p.161
A Reaction
This is the opposite of the approach in the Peano Axioms, where induction is used to define the natural numbers.