Aristotle's core conception of abstraction ( Open image in new window ) is: selective attention . Although he at times uses "abstraction" in the sense of 'subtraction " of the Greek mathematicians, Aristotle extends the use to other cases where certain aspects of an object are focused upon and selected out. Aristotle then allows for these aspects to be treated in the sciences as if they were subjects in their own right, in a way to which Frege would object. Unlike the later British empiricists, Aristotle takes abstraction to isolate real aspects of objects and not to construct concepts pertaining only to how we think of the world.