|Abstraction: Subsumption of objects by non-consideration of certain properties. See also equivalence relation, concretion, concreta, indiscernibility.|
Books on Amazon
Introduction/Abstract Objects/Abstraction/Wright: Thesis: Sets as well as directions and numbers are to be introduced by abstraction.
Field: Example simple abstraction: is suitable for us saying that our talk of directions refers to parallelism. - But that does not quite work accordingly for numbers as it does for non-numeric talk (and "non-set theory").
Homomorphism/Field: (structure-preserving representation) is the bridge to find abstract counterparts to concrete statements ((s) observation statements) - Semantic Ascent/Abstract Counterparts: we would always obtain the results without them. - ((s) otherwise they would be something else.) - Field: we save a lot of time with this.
Realism, Mathematics and Modality Oxford New York 1989
Truth and the Absence of Fact Oxford New York 2001
Science without numbers Princeton New Jersey 1980