Monday, April 05, 2010

An argument from the Privacy of Mental States

1. Mental states are immediate, first-hand, and private.


2. Physical states are public, and available to multiple observers.

3. Therefore, mental states and physical states cannot be identical.

15 comments:

Joshua Allen said...

Lucid dreams are a special variant of this case. For a person who has never had a lucid dream, the existence of lucid dreams needs to be taken on faith from witness accounts. And since lucid dreams are relatively rare, it raises the question of just how many eyewitnesses one needs to call "private" evidence "public".

Mark said...

I take 1. to mean: I have introspective access to my own mental states, and no one else has such access to my mental states. That is, I and I alone can have knowledge about my mental state not on the basis of anything beyond my mental state.

How should we understand 2. in such a way that it's inconsistent with this interpretation of 1.?

Steven Carr said...

'Mental states are immediate, first-hand, and private.'

God doesn't know what you are thinking?

Matthew said...

God doesn't know what you are thinking?

I know that you are thinking that theism provides a counterexample. But your mental state "Haha, stupid theists, this is a counterexample" is still private.

Steven Carr said...

Private in what sense?

In the sense that this imaginary god does not have access to it and does not know what it is?

Private in the sense that this imaginary all-powerful god could not instantly create a duplicate me with exactly the same mental state?

Private in the sense that if you are angry, then nobody,not even God, can ever detect that anger?

Steven Carr said...

MATTHEW
I know that you are thinking that theism provides a counterexample.

CARR
How did you know what I was thinking?

I thought mental states were private.

Gordon Knight said...

If God can know what it is like to be us, then God can know what it is like to be a finite being. But how can an infinite God get such knowledge? Perhaps from the incarnation.

Mind reading is a logical possiblity. It might just be a contingent fact that each of us does not "introspect" someone else's thoughts. But we still would not be aware of them in the same way (if we were, then they would be our thoughts!

terri said...

Mental states are private only in the sense that we don't have scanners hooked up to our heads portraying our brain functions for other to see.

In a world in which technology is rapidly advancing...mental states are becoming less and less "private" than they once were.

Also...an adrenaline rush, rapid heartbeat, the beginning of organ failure, etc. are physical states which might not be "publicly observable".

I don't think this argument holds up well in several different areas.

Anonymous said...

The argument isn't that we can't make inferences (given our own subjectivity, reports, etc), even increasingly accurate ones, about what a person is experiencing. It's that the inference is exactly that - correlation of third person observations upon which we make an inference. The experience itself is not third-person correlation but first-person experience.

Stabbing a person in the hand and being correct about the claim "You're experiencing discomfort right now!" doesn't help out here. No do increasing technological advances on this front ('I bet you're lying!' 'I bet you're thinking about Russia!' etc.)

bossmanham said...

If God can know what it is like to be us, then God can know what it is like to be a finite being. But how can an infinite God get such knowledge? Perhaps from the incarnation.

Well I would dispute that God knows what it's like to be us. That's a contradiction. For God to know that He would actually have to be us (all of us individually). I would say that God knows all propositional truth, but it would be logically incoherent to say God knows what it's like to be Clint Eastwood, for instance.

The Family said...

Although I agree with you that mental properties are not fully explained in the classical physical facts, doesn't the Schrödinger's cat experiment of quantum physics somewhat contradict your idea that all of the physical facts are public?

Doug Benscoter said...

bossmanham, I think you're right to distinguish between propositional knowledge and personal knowledge. There's a difference between knowing everything about Clint Eastwood (propositional knowledge) and knowing what's it's like to be Clint Eastwood (a type of personal knowledge).

I think Gordon is generalizing about knowing it's like to be human, as opposed to any particular human like you or me. The Incarnation would make it possible for God to know what it's like to be human, but not necessarily what it's like to be any non-Jesus human person.

Doug Benscoter said...

Victor, the argument you have posted is a lot like Descartes':

1. My body is dubitable.
2. My mental activity is indubitable.
3. Therefore, my body and my mental activity are distinct.

Both arguments make use of Leibniz' Law.

J said...

Or, the ...Skinnerian variation

1. Subjective mental states are immediate, first-hand, and private, therefore mostly useless as data or evidence.


2. Physical states, and external behaviors are public, and available to multiple observers, and capable of measurement to some extent by scientists, psychologists, and sociologists.

3. Therefore, researchers should not waste a great deal of time and money on alleged mental states but instead concentrate on what can be known by examining physical states.

(that's not to say mental states are completely meaningless, but generally not useable as data, except via brain scans, MRIs, etc)

MC said...

Re: Terri:

Your comment is apt; mental states are increasingly less "private" than they once were.

http://www.dailymotion.com/video/x9pzcq_the-present-future-of-mindreading-t_news

Cf. Haynes, JD. et al. (2007). "Reading Hidden Intentions in the Human Brain", Current Biology, 17, pp. 323-328

Studies like this come out at least once a month now, showing surprisingly accurate accounts, with increasing accuracy, of mindreading abilities by computers and researchers.