Thursday, February 1, 2018

Leibniz: a reductionist of the mental?

Leibniz talks about all substances having unconscious perceptions, something that threatens to be nonsense and to make Leibniz into a panpsychist.

I wonder if Leibniz wasn’t being unduly provocative. Let me tell you a story about monads. If Alice is as monad, Alice has a family of possible states, the Ps, such that for each state s among the Ps, Alice’s teleological features make it be the case that there is a state of affairs s* concerning the monads—Alice and the other monads—such that it is good (or proper) for Alice to have s precisely insofar as s* obtains.

This seems a sensible story, one that neither threatens to be nonsense nor to make its proponent a panpsychist. It may even be a true story. But now note that it is reasonable to describe the state s of Alice as directly representing the state of affairs s* around her. Teleological features are apt to be hyperintensional, so the teleological property that it is good for Alice to have s precisely insofar as s* obtains is apt to be hyperintensional in respect to s*, which is precisely what we expect of a representation relation.

And it seems not much of a stretch to use the word “perception” for a non-derivative representation (Leibniz indeed expressly connects “perception” with “representation”). But it doesn’t really make for panpsychism. The mental is teleological, but the teleological need not be mental, and on this story perceptions are just a function of teleology pure and simple. In heliotropic plants, it is good for the plant that the state of the petals match the position of the sun, and that’s all that’s needed for the teleological mirroring—while plants might have some properly mental properties, such mirroring is not sufficient for it (cf. this really neat piece that Scott Hill pointed me to).

If we see it this way, and take “perception” to be just a teleological mirroring, then it is only what Leibniz calls apperceptions or conscious perceptions that correspond to what we consider mental properties. But now Leibniz is actually looking anti-Cartesian. For while Descartes thought that mental properties were irreducible, if we take only the conscious perceptions to be mental, Leibniz is actually a reductionist about the mental. In Principles of Nature and Grace 4, Leibniz says that sometimes in animals the unconscious perceptions are developed into more distinct perceptions that are the subject of reflective representation: representation of representation.

Leibniz may thus be the first person to offer the reduction of conscious properties to second-order representations, and if these representations are in fact not mental (except in Leibniz’s misleading vocabulary), then Leibniz is a reductionist about the mental. He isn't a panpsychist, though I suppose he could count as a panprotopsychist. And it would be very odd to call someone who is a reductionist about the mental an idealist.

Of course, Leibniz doesn’t reduce the mental to the physical or the natural as these are understood in contemporary non-teleological materialism. And that’s good: non-teleological naturalist reductions are a hopeless project (cf. this).

1 comment:

Alexander R Pruss said...

For a fine analysis of just how a Leibnizian reduction might or might not look, see: