Full Idea
Abstraction is preceded by an earlier stage, in which we learn to recognize instances; before I can conceive of the colour violet in abstracto, I must learn to recognize instances of this colour when I see them.
Gist of Idea
Before we can abstract from an instance of violet, we must first recognise it
Source
H.H. Price (Thinking and Experience [1953], Ch.II)
Book Reference
Price,H.H.: 'Thinking and Experience' [Hutchinson 1953], p.35
A Reaction
The problem here might be one of circularity. If you are actually going to identify something as violet, you seem to need the abstract concept of 'violet' in advance. See Idea 9034 for Price's attempt to deal with the problem.
Related Idea
Idea 9034 There may be degrees of abstraction which allow recognition by signs, without full concepts [Price,HH]