Here’s an argument against the claim that a human is sometimes (or always) a proper part of a larger whole such as a committee or an ecosystem, assuming constituent ontology.
An object is human iff humanity is a proper part of the object.
Proper parthood is transitive.
If a human x is a part of y, then x’s humanity is a proper part of y. (1 and 2)
So if a human is a proper part of something, that something is a human. (1 and 3)
No human is a proper part of a human.
So, no human is a proper part of anything. (4 and 5)
It seems that constituent ontologists have to have a pretty restricted theory of composition.
One way out is to distinguish “ontologically constituent parthood” from “integral parthood”, and say that an object is human iff humanity is an ontologically constituent part. Then the conclusion of the argument is going to be that no human is an ontologically constituent part of anything. But this requires multiplication of fundamental ideology.
There is another a way out of this. Let’s suppose that there are proper parts and immediate proper parts, with proper parthood being grounded in immediate proper parthood. Thus, perhaps, my fingers are immediate proper parts of my hand, my hand is an immediate proper part of my arm, and so on. Mediate parthood is then a chain (of length 0 for improper parts) of immediate parthood. There is no multiplication of fundamental ideology, since parthood is defined in terms of immediate proper parthood. Moreover, this is not unmotivated. Parthood seems intuitively hierarchical rather than flat. My big toe is a part of my leg because it is a part of my foot.
Now, notice that if we say this, we might hypothesize that an object’s essence is an immediate proper part of it. (Dialectical note: A constituent ontologist who accepts (1) and who buys the concept of immediate proper parthood has to agree with this hypothesis. For if my humanity were a mediate part of me, then I would have a proper part of which my humanity was a proper part, and by (1) that proper part would be human. But clearly no human is a proper part of me.)
Given that hypothesis, we can modify the constituent ontology claim (1) to:
- An object is human iff humanity is an immediate proper part of the object.
And now humans can be parts of larger wholes, without infecting them with humanity.
