Full Idea
If the definition of a circle is based on 'locus of a point', this tells us what a circle is, and it does so by revealing its generating principle, what it takes for a circle to come into being.
Gist of Idea
A definition of a circle will show what it is, and show its generating principle
Source
E.J. Lowe (What is the Source of Knowledge of Modal Truths? [2013], 6)
Book Reference
-: 'Mind' [-], p.17
A Reaction
Lowe says that real definitions, as essences, do not always have to spell out a 'generating principle', but they do in this case. Another approach would be to try to map dependence relations between truths about circles, and see what is basic.
Related Idea
Idea 16540 Defining an ellipse by conic sections reveals necessities, but not the essence of an ellipse [Lowe]