Full Idea
Arithmetic, geometry and sciences of that kind only treat of things without taking any great trouble to ascertain whether they are actually existent or not, and contain some measure of certainty.
Gist of Idea
Arithmetic and geometry achieve some certainty without worrying about existence
Source
René Descartes (Meditations [1641], §1), quoted by Alan Musgrave - Logicism Revisited §4
Book Reference
-: 'British Soc for the Philosophy of Science' [-], p.110
A Reaction
This is Musgrave's earliest quotation which seems to take the if-thenist view.