Abstraction turns equivalence into identity, but there are two ways to do it. Given the equivalence relation of parallelness on lines, the #1 way to turn equivalence into identity by abstraction is to consider equivalence classes of parallel lines. Thus two lines are equivalent iff their equivalence classes are identical. The #2 way is to consider the abstract notion of the direction of parallel lines. This paper developments simple mathematical models of both types of abstraction and shows, for instance, how finite probability theory can be interpreted using #2 abstracts as “superposition events” in addition to the ordinary events. The goal is to use the second notion of abstraction to shed some light on the notion of an inde finite superposition in quantum mechanics.

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