Tuesday, March 12, 2024

The epistemic gap and causal closure

In the philosophical literature, the main objection to physicalism about consciousness is the epistemic gap: the alleged fact that full knowledge of the physical does not yield full knowledge of the mental. And one of the main objections to nonphysicalism about consciousness is causal closure: the alleged fact that physical events, like our actions, have causes that are entirely physical.

There is a simple way to craft a theory that avoids both objections. Simply suppose that mental states have two parts: a physical and a non-physical part. The physical part of the mental state is responsible for the mental state’s causal influence on physical reality. The non-physical part explains the epistemic gap: full knowledge of the physical world yields full knowledge of the physical part of the mental state, but not full knowledge of the mental state.

5 comments:

Chris Mathew said...

Ergo, epiphenomenalist dualism?

Alexander R Pruss said...

But the qualia are not epiphenomenal on this story: they are causal in virtue of their physical parts.

Heavenly Philosophy said...

I don't think this accounts for epistemic closure. When one experiences a mental state, they do not experience an arrangement of particles (whatever that could mean.) In another post you say, "But it doesn’t seem at all clear to me that the quale positively doesn’t have a shape. It’s just that it is not the case that it positively seems to have a shape." The problem with that is that you cannot fail to grasp the entire content of a mental experience when you are experiencing it, because the experience of the mental state is identical to the mental state. The experience is all that's being referred to by "mental state." So, you cannot miss something that isn't there when experiencing it. If you don't experience the mental state's shape, then it doesn't have one, because that's all what the mental state is: the experience of it.

Alexander R Pruss said...

If we experienced all the features of a mental state, then we could settle all sorts of ontological questions _a priori_. For instance, consider a version of Thomism on which every finite, not just finite substances, is a composite of essence and existence. Then simply by looking at the whiteness on the screen in front of me I could refute the Thomistic thesis, because I don't see a separate essence and a separate existence in my experience. The point generalizes: we can't do much in the way of ontology simply by staring at our experiences.

I also think it is false that the experience of the mental state is identical to the mental state. Some mental states are first-order experiences. An experience of that mental state is a second-order experience. Sometimes we have just the first-order experience without the second-order one, and sometimes we have both. And we almost never have a third-order experience. And even in cases where we have second-order experiences, I suspect it is rare that the whole of the first-order experience is the content of the second-order experience. Just as first-order experiences tend to miss much of the detail of the world around us, the second-order experiences tend to miss some of the detail of the first-order experiences.

Jack said...

Dr. Pruss, is "Norms, Natures, and God still in progress?