Q&A: The Principle of In…
The Principle of In…
Question
Hello!
In several places in your various books you brought up the “principle of individuation” formulated by Aristotle, according to which there can be two objects that are equal in all their properties and yet are still two different entities.
You also cited Leibniz, who disagreed with Aristotle in his famous “Identity of Indiscernibles” principle.
In all those places you adopted Aristotle’s position. In one place you even wrote that Leibniz’s position is absurd.
However, I did not find that you explain (even briefly!) why you hold this view. At most, following Bergmann, you refuted Leibniz’s “proof.” Is this really only intuition? Aren’t there debates, probabilities, and different arguments here? Has nothing at all been written about this in the philosophical literature?
I would be happy to hear your thoughts on this.
Have a good week!
And this is also a good place to thank you for the wonderful site! Much appreciated, and much success!
Answer
Hello.
I believe I explained this in Two Carts.
As for the matter itself, I don’t think an explanation is necessary. The starting point is that Aristotle is right, because it is clear that if you distinguish between a thing and its properties, then identity in properties does not entail identity between the entities. Why should identity in properties make the two entities one? What is the connection between difference in properties and separation in individuation?
What remains is Leibniz’s proof, which ostensibly forces us to give up this intuition. So once the proof has been refuted, we return to the Aristotelian starting point.
I assume this has been discussed in the philosophical literature, but unfortunately I am not familiar with it. I assume you can search philosophical databases or ask experts in the field.
Discussion on Answer
As I explained there, ultimately the roots of the dispute are always anchored in the basic assumptions, meaning the initial intuitions—unless someone has a simple logical mistake, which usually is not the case.
It is hard for me to believe that this intuition is not self-evident to you. You have two drops of water. Now compare all their properties one by one. Have they become one? Alternatively, do you think there is nothing in a chair beyond the totality of its properties? After all, there is something that bears all those properties—that is, those are its properties, no?
If that is not self-evident to you, then I have no better arguments. But also see the passage I cited there from Borges’s Fictions, which shows the absurdity created by the conventionalist assumption. Borges shows that according to conventionalism one could also unite into a single concept a collection of properties that have no connection whatsoever to one another—the tone of voice of a bird screaming in the distance, together with the color of a cloud in Australia and the strength of the wind in Scandinavia. If there is no entity that bears all those properties, then there is no obstacle to defining those three properties as an entity. See there for a brilliant description of the implications of conventionalism.
Thank you very much, I’ll look into it.
Thank you for the answer.
In Two Carts you indeed only distinguish between the thing and its properties. But that very point is the dispute itself. Leibniz argues that the thing in itself is the collection of all its properties. That assumption was not refuted at all.
My question is: do you have a logical refutation, or at least a persuasive conceptual one, of Leibniz’s assumption?
Is it really the case that your entire position on this matter is rooted only in intuition? (And I do not at all belittle the power of intuition; it’s just that, what can I do, in this matter I don’t have such a strong intuition.)