Monday, January 10, 2011

Souls, Mental States and Brain States

Here are a couple of logical arguments I've been playing with:

Let S = a human person

Let M = mental states

Let B = brain states

1. If S has M, then S has B.

2. S has M.

3. Therefore, S has B.

I know the argument is valid, but some might question its soundness. And maybe what I'm really trying to prove, which the argument above does not is the following:

1. If S has M, then necessarily S has B.

2. S has M.

3. Therefore, necessarily S has B.

But then have I now raised problems pertaining to the modal operator "necessarily"? I'm not sure. Comments anyone?


Anonymous said...

Hi Edgar,

As you know, if the premisses of an argument are valid then the conclusion "necessarily" follows. Both your premisses are validated by experience, IMO, but I suspect you are instead attempting to impute logical necessity into a premiss somehow. Our own neuro-biological makeup is ostensibly thought-action/action-thought based, but proving such a rationale through logic alone might require some kind of experiential qualifier so as to mitigate arguments by dualists (i.e. the best evidence from experience suggests...).

Then again, perhaps there is a way to frame the argument such that it cannot be refuted. In the end, however, people will believe what they find most appealing, not what they find most revealing.



Edgar Foster said...

Hi Nathan,

Your observations are appreciated. I am trying to establish an argument that is valid which is easier than establishing a sound argument, although I believe what I've written is sound (i.e. the premises and conclusion are true).

I also concur with your point about effective arguments. Ultimately, people are going to being what makes them comfortable (for the most part) but my research has convinced me that the weight of evidence from the philosophy of mind, neuroscience and theological anthropology is that we are completely physical. That is, we do not have an immortal element known as a soul.