Full Idea
To every subject, its appropriate level of abstraction.
Gist of Idea
Each subject has an appropriate level of abstraction
Source
David M. Armstrong (What is a Law of Nature? [1983], 01.2)
Book Reference
Armstrong,D.M.: 'What is a Law of Nature?' [CUP 1985], p.7
A Reaction
Mathematics rises through many levels of abstraction. Economics can be very concrete or very abstract. It think it is clearer to talk of being 'general', rather than 'abstract'.