Phenomenal Concepts and the Private Language Argument - mm
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Phenomenal Concepts and
Private Languages
David Papineau
British Postgraduate Philosophical
Association
KCL July 14 2009
Phen Concepts and PLA 1 Mary and Phen Concepts 1
The Plan
1 Mary and Phenomenal Concepts
2 Are Phenomenal Concepts inconsistent
with the PLA?
3 If so, is this bad for Phenomenal
Concepts, or bad for the PLA?
Phen Concepts and PLA 1 Mary and Phen Concepts 2
Conceivability Arguments for
Dualism
We can conceive of a being who is
physically just like us, but has no
conscious feelings (a ‘zombie’).
So conscious feelings are extra to the
material realm.
We might all agree that this is not a good
argument. But what exactly is wrong
with it?
Phen Concepts and PLA 1 Mary and Phen Concepts 3
Type-A Physicalism
Back in the 1970s and 1980s we responded to this
argument by denying the conceivability premise.
Maybe we can conceive of C-fibres without
pains. But once you fill the rest of the physical
framework, as with a zombie, the absence of
feelings ceases to be conceivable.
(If it walks like a conscious person, and talks like a
conscious person, . . .)
But Jackson’s Mary argument undermined this
line.
Phen Concepts and PLA 1 Mary and Phen Concepts 4
Frank Jackson’s Knowledge
Argument
Mary is an omniscient colour vision scientist who has never
had any colour experiences herself—until one day she
sees a red rose.
Jackson's argument:
(a) Before that day, Mary knew about all physical aspects
of colour experience
(b) The she learns about another aspect--what it is like to
see something red
Therefore
(c) There is at least one non-physical aspect of colour
experience
Phen Concepts and PLA 1 Mary and Phen Concepts 5
Type-A Physicalism Kyboshed
This looks in tension with the Type-A line. Mary knew everything
there is to know about how conscious persons walk and talk,
but didn’t yet know what it was like for them. It looks as if the
facts about brains and behaviour leaves it conceptually open
what if anything is going on consciously.
Sure, 'Type-A' physicalists--Dennett, Ryleans, neo-behaviourists,
David Lewis, Analytic Functionalists, Wittgensteinians?—may
try to deny premise (b) which says that Mary acquires some
new knowledge. (She may not have had the experience
before, but she didn’t then lack any knowledge.)
But this is highly implausible, for reasons that will become even
more clear later on.
Phen Concepts and PLA 1 Mary and Phen Concepts 6
Phenomenal Concepts
So 'Type-B' Physicalists allow that Mary
does acquire new knowledge, but only at
the level of concepts.
Mary gets a new 'phenomenal' concept, Ø,
which refers to the same state as her old
physical concept seeing redly.
Phen Concepts and PLA 1 Mary and Phen Concepts 7
What Mary Learns
So now she knows ripe tomatoes cause Ø, where before
she only knew ripe tomatoes cause seeing redly.
But this doesn't involve knowledge of a new dualist mental
property, anymore than learning Bristol is the birthplace
of Cary Grant, when previously you only knew Bristol is
the birthplace of Archie Leach, involves knowledge of a
new person.
By the same coin, Mary now knows that seeing redly = Ø,
when before she only knew seeing redly = seeing redly.
But no new dualist property is required.
Phen Concepts and PLA 1 Mary and Phen Concepts 8
Phenomenal Concepts Rule
Contemporary dualists (Chalmers, Bealer, old Jackson)
agree about the phenomenal concepts, but use a
contentious semantic premise to argue that the a
posteriority of seeing redly = Ø entails its falsity.
So pretty much everybody in this debate now accepts
phenomenal concepts. There are scarcely Type-A
physicalists left. Dennett. And Jackson himself. (He
became embarrassed about being a dualist, and so had
to deny either (i) Mary gets a new phenomenal concept
or (ii) the dodgy semantic premise. Amazingly, he is so
attached to the latter that he (alone) has joined Dennett
in denying his own knock-down argument for
phenomenal concepts.)
Phen Concepts and PLA 1 Mary and Phen Concepts 9
Does Mary have Private Terms?
So—is there something about Mary that Wittgenstein wouldn't
like?
After all, her ‘phenomenal concept’ is posited as applying
specifically to a kind of sensation. Moreover, it is a concept
that can only be possessed by people who have had that
sensation themselves.
But it’s not immediately clear why Mary should be ruled out by
the PLA. I take it that Wittgenstein did not wish to deny that
we can refer to sensations in the direct way Mary now can.
Nor is it clear that he would wish to deny that having had the
sensation yourself is necessary for such reference.
Phen Concepts and PLA 2 PLA -> No Phen Concepts? 10
Phenomenal Concepts
Reconsidered
Maybe we were to quick to say that Mary
acquired a special new concept for her own
private sensation.
Perhaps on coming out the room, Mary simply
gets better at applying the public concept of
seeing redly that she already shared with
the general community. (Cf the ‘ability
hypothesis’.)
Phen Concepts and PLA 1 Mary and Phen Concepts 11
Mariana and the Piece of Paper
But now consider this variant. Mariana isn't
shown a red rose, but a coloured piece of
paper—and isn't told what colour it is. I say
she too will form a concept of the type of
experience she then had.
After all—she may conjecture I'll have Ω
again today, or Ω is caused by lush
grass—and these conjectures will surely
be true or false.
Phen Concepts and PLA 2 PLA -> No Phen Concepts? 12
Let’s assume the child is a genius
But note that Mariana won't know in any
public terms which colour experience Ω is.
So any word—’seeso', say—that she coins
to express it will be private, at least in the
sense that its meaning will be
incommunicable to anyone else. ('Well,
let's assume the child is a genius and itself
invents a name for the sensation. . .')
Phen Concepts and PLA 2 PLA -> No Phen Concepts? 13
‘Private’ ≠ ‘Solitary’
Still, perhaps this incommunicability is
superficial, like that of an as-yet unrescued
Crusoe who hasn't had a chance to
explain his terminology to anybody.
That is, maybe Mariana's term isn't
necessarily private. Maybe 'seeso' has
been assigned meaning in way that
satisfies the appropriate standards of
checkability, etc, but Mariana simply hasn't
yet had a chance to explain it to anyone.
Phen Concepts and PLA 2 PLA -> No Phen Concepts? 14
Mariana makes herself understood
Now, I myself certainly think that, given
propitious circumstances, Mariana will be
able to communicate her meaning to
others.
Suppose that it becomes common
knowledge between her and others that
the piece of paper was green. Then they
will all know that 'seeso' refers to: seeing
greenly.
Phen Concepts and PLA 2 PLA -> No Phen Concepts? 15
Identifying Mariana’s Referent
But let's look a bit more closely at what is going on
here.
Mariana and her friends know that there is a publicly
accessible kind of experience (maybe physical,
maybe functional role, maybe even non-physical
functional realizer) called 'seeing greenly', which is
typically caused by green things.
And they figure out that Ω = seeing greenly/'seeso =
seeing greenly'. And so everything is fine.
Phen Concepts and PLA 2 PLA -> No Phen Concepts? 16
An Argument for Physicalism?
But is it fine for Wittgenstein? Some would
argue at this point that it is indeed fine for
him precisely insofar as the referent of
Ω/'seeso' turns out to be a publicly
accessible item.
Thus my colleague Jim Hopkins holds that
Wittgenstein has an argument for
physicalism here (otherwise Mariana-style
references wouldn't be to anything public).
Phen Concepts and PLA 2 PLA -> No Phen Concepts? 17
Meaning needed from the start
But I doubt that this general story would be all right
for Wittgenstein. Note crucially that the
discovery that Ω = seeing greenly/'seeso =
seeing greenly' is a posteriori for Mariana and
her friends. And this surely requires that
Ω/'seeso' already had a determinate meaning
prior to their knowledge of the greenness of the
paper.
Phen Concepts and PLA 2 PLA -> No Phen Concepts? 18
Seeming Right is Being Right
How did that happen?
Mariana looked inwards and gave the name
Ω/'seeso' to her sensation.
At that stage there was no possibility of any
check on later uses of Ω/'seeso' being
used with the same meaning.
And so no such checkable difference
between being right and seeming right in
this.
Phen Concepts and PLA 2 PLA -> No Phen Concepts? 19
A Beetle in a Box
When we later correlate uses of Ω/'seeso'
with something publicly accessible,
surely that's just like correlating 'S' with
movements of the manometer.
And for Wittgenstein this doesn't vindicate
the prior usage of 'S' as referring to
anything, but simply renders it a new
public term for which any prior supposed
referent has become irrelevant.
Phen Concepts and PLA 2 PLA -> No Phen Concepts? 20
Two Ways to Go
Assuming there is an incompatibility between
Phenomenal Concepts and the PLA, there are
two ways to go.
(a)The PLA shows that Mariana does not have a
contentful concept.
(b) Mariana refutes the PLA.
Let me broaden out the issues.
Phen Concepts and PLA Phen Concepts OR PLA 21
Judgement and Rules
I take it that behind the PLA lies a broader picture
of contentful judgement.
Judgements are constituted by rules. You can
judge that p insofar as you are sensitive to a
rule governing such judgements.
The nature of such rules is not straightforward, but
at the least they require some kind of public
checkability, some answerability to public
standards that ensure a difference between
seeming right and being right.
Phen Concepts and PLA Phen Concepts OR PLA 22
No Rules
Here is an alternative view of contentful judgement.
We have a stock of concepts that are designed to lock onto
entities in our environment.
Thus when confronted with a zebra I might take an animal
species concept from the shelf, so to speak, and then
from then on this concept refers to the species: zebra.
Nothing more is needed. In particular no rules are needed
to bring it about that I can re-use the term with the
same meaning on future occasions. Next time I judge
zebra I will be right if it is a zebra (the species I locked
on to) and not otherwise.
Similarly I can form concepts of individual animals, people,
metals, houses, . . . and of types of experience.
Phen Concepts and PLA Phen Concepts OR PLA 23
Conclusion
Mariana's manifest ability to refer to her
experience seems to me a powerful
reason for preferring the second
view to the first.
Phen Concepts and PLA Phen Concepts OR PLA 24
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