Tuesday, August 3, 2010

Is Leibniz an idealist?

I continue to be surprised why Leibniz gets described as an idealist. If Leibniz is an idealist, Dretske is committed to idealism, too, and that seems mistaken. Leibniz thinks everything has soul, and every soul has perceptions, but not all the perceptions are conscious, and some souls have no conscious perceptions. As far as I can tell, the claim that x has a soul with perceptions comes down to two things: (a) x has a substantial form, and (b) x has representations. Claim (a) holding for all x does not imply idealism: Aristotle surely does not count as an idealist. Claim (b) holding for all objects x is something that Dretske is committed to, assuming that we, reasonably, take having information to entail having representations (information surely represents; and on a Dretskean view it seems pretty easy to argue that everything that can be affected by something else carries information). We could take this to be an argument that Dretske is an idealist, but it is better to take it to be an argument that Leibniz is not.

6 comments:

todd said...

Hi Alex. The question is vexed, and, I'm sure you know, widely disputed. But I think Leibniz's idealism has more to do with the claim that NOTHING BUT simple substances exist, and, in them, nothing but perception and appetite. That entails that if there are bodies, they are reducible to souls and their mental states, i.e., they are not mind-independent. That certainly gets him in the neighborhood of idealism! The debate, I think, is about whether he stays in this neighborhood throughout his career.

Derrick said...

@ Todd: Isn't that just panpsychism?

Alexander R Pruss said...

I wonder if there is any difference between idealism and panpsychism? The former says only minds exist. The latter that everything is a mind.

Alexander R Pruss said...

I guess I read L like this: monads are components of bodies. But what makes them spatiotemporal and joined into bodies is the mental stuff.

todd said...

I see that panpsychism and idealism agree that, at bottom, nothing exists but minds and their contents. But panpsychism, I think, goes further. I understand it to be the doctrine that every body is, in some sense, ensouled or has a thought of its own. Reductionism about bodies can avoid this doctrine. One way would be to identify bodies not with a collection of thoughts (as Berkeley appears to do) but with the contents of thoughts. On such a reduction, bodies are like characters in the stories told by our (human) perceptions. This would be idealism, but not panpsychism. For the bodies themselves are thoughtless. For the record, I think this would be a fair characterization of Kantian idealism. Also for the record, I should mention Bob Adams's book, Leibniz: Determinist, Idealist, and Theist; the section on idealism is, I think, the starting point for scholarly debate about this issue.

Alexander R Pruss said...

Todd:

Suppose that there is a spiritual substance that doesn't think. Then panpsychism is false. So panpsychism cannot simply be the claim that all bodies think.

Maybe, then, panpsychism is the conjunctive claim: all genuine objects think, and all genuine bodies are objects?

But it just doesn't seem like the second conjunct is a part of panpsychism.

So, maybe, we should leave panpsychism as the claim that all things think (in a broad sense), but now define idealism as the claim that all bodies are reducible to thoughts.

But then anyone who thinks there are no bodies (in some sense, I think that's true--I do have a body, but I do not think this is to be analyzed by positing an entity, body, which I have) counts as an idealist.

Maybe, then, to be an idealist you have to both believe in bodies and believe they are reducible to thoughts?

If so, then on my reading Leibniz is not an idealist, because I think he thinks of the monads as components of the bodies, and since the monads are not reducible to thoughts, surely neither are the bodies of which they are parts.