Full Idea
The phrase 'abstracted from' does not refer to the mental process of abstraction by disregarding features of concrete objects, in which many nineteenth century thinkers believed; it is a logical (not mental) process of concept-formation.
Gist of Idea
To 'abstract from' is a logical process, as opposed to the old mental view
Source
Michael Dummett (Thought and Reality [1997], 1)
Book Reference
Dummett,Michael: 'Thought and Reality (Gifford Lectures)' [OUP 2006], p.11
A Reaction
I take Frege's attack on 'psychologism' to be what dismissed the old view (Idea 5816). Could one not achieve the same story by negating properties in quantified logical expressions, instead of in the mind?
Related Idea
Idea 5816 Frege said concepts were abstract entities, not mental entities [Frege, by Putnam]