Sometimes when we talk about someone we might say something like "she has a colour" or "she has an age". But we do not say "She is age" or "She is colour", so, where do the terms "Colour" and "Age" (and other terms like that) fit into Aristotle's works?
Additionaly we say things like "she is 60 years old" when we know that her age is 60 years. So there must be a connection somewhere between the predicated "is 60 years old" and "age" i just can't see where?
Aristotle's thought has a splendid internal coherence. Hence, we ought to take into account his whole thought when a doubt occurs about interpretation.
Aristotle considers statements in the syllogistic form which consists of a subject term, a predicate term and a copula that unites them. Therefore, we have to analyse any statement in this logical form, regardless of however it is expressed in natural language.
In the light of this remark, let us review Aristotle's list of categories:
The category of quality characterises a thing. The typical examples that fall in this category are the sensible features. ‘Colour’ and ‘age’ are two of such features.
While we analyse the statements, we may be forced into unnatural paraphrases in S+P structure, but that is not an unusual situation that we face when casting a structure onto a natural language expression, specifically, in logic. Thus, it remains up to one's choice how to paraphrase “is 60 years old” (viz. as “has the age of” or any way else).
