Phenomenalism Stopping the pendulum?

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Phenomenalism
Stopping the pendulum?
The general idea
• Classical Idealism (Berkeley): Physical objects are
actually (structured) collections of ideas.
• More recent (and more modest) efforts: Carnap, Die
Logische Aufbau der Welt. Carnap tries to come up with
an analysis of talk about the world in terms of a. Logical
structure b. Space and time c. Sensible properties.
(Red at place p and time t as a ‘protocol sentence’.)
• Others: Attempts to analyze ordinary object talk as
some kind of theory grounded in immediately observable
features of our sensory experiences (some think there
really is a parallel here with scientific theories).
Direct (Naïve) Realism
• …while the verb ‘to see’ has many uses…its
primary use is one in which a person is said to
see a physical object and to see that it is of a
certain colour…
• Sellars winds up defending some such view (but
that’s later).
• A more naïve realism holds that things seen
(whatever they may be) always are as they
appear to be– this Sellars does not hold, so he
adopts ‘direct’ realism to distinguish the view he
will defend from this more naïve realism.
The phenomenalistic theme
• Objects really do have the sorts of properties they look to have.
• Direct realism holds that the standard use of colour predicates is in
contexts like: O is red at place P.
• Looks-talk must then be explained in terms of this basic sort of
claim.
• Classical phenomenalism has a different starting point: A collection
of ‘more basic’ objects which have these properties in a ‘more basic’
way. Ayer calls these objects sense contents.
• The idea is that a physical object is redp, i.e. red in the physical
sense, if and only if there are reds sense contents that are parts of it
under normal viewing conditions.
• The object ‘merely looks red’ when there are reds sense contents
that are parts of the object, but are not produced under normal
viewing conditions.
Saving sensory judgments in cases
of illusion
• The main point for the phenomenalist is that
when something merely looks redp, this is
because there really is a reds sense content
being experienced.
• Further, all the sense contents ‘produced’ by the
object, under normal and abnormal viewing
conditions, are ‘parts’ of the object.
• The DR, on the other hand, says that only parts
of physical objects have colours– and physical
objects and their parts are publically
observable, i.e. they belong to the
intersubjective world.
Surfaces and slippery slopes
• It seems right to say that, when we call (say) a car red,
what we mean is that it has a red surface.
• Such a surface is not 2-dimensional– it’s a 3D physical
object, the (thin) layer of paint that covers the car.
• But it’s tempting to move in a more metaphysical
direction, and say that what really has a colour is a really
2D surface, and to conclude that what we ‘really’ see is
such 2D surfaces (the rest of 3D physical objects being
inferred from the surfaces we see).
• Even if we make this move, we’re still operating in the
public world– we’re not yet phenomenalists…even
though we may now describe physical objects as ‘made
up’ of actual and potential (‘exposable’) colour surfaces.
Rejecting surfaces
• There are a few ways to relate this talk of surfaces back to the
colours of 3D objects.
• But it’s not pretty; we can make lots of different exhaustive slicings
across an apple, and to say the apple is made of all of these seems
redundant at best.
• It seems we should either say the 3D object comes first, and its
slices are dependent and only actual when the thing is sliced, or the
object is really a collection (continuum) of colour points, and both the
object and the slices are (3D and 2D) collections of such points.
• The last seems dubious; the first makes the slices depend on the 3D
object.
• The real mistake Sellars is worried about, though, is the distinction
between what is really seen, viz. the surface and what we then
believe/infer from it (the object). This is an epistemic step towards
phenomenalism, since it leads to the idea of ‘unattached surfaces’
that we can also see, and to an epistemic conservatism about what
we see that makes the phenomenalist account of illusions tempting.
Still some distance to go
• ‘Pure seeing’ is introduced here for the new D.R.
view that says, what we see (really, purely) is
just surfaces, and we then infer the objects that
have them.
• But so far, the D.R. says there is no dagger that
Macbeth sees, and this new D.R. agrees.
• However, the new D.R. may be tempted to say
there was a dagger-shaped surface there (with
no dagger ‘inside’ it?).
• This step removes the surfaces from the public
world and shifts them to the ‘theatre of the mind’
where the classical phenomenalist is at home…
Resistance
• The new D.R. need not go this way– she can keep her new surfaces
firmly linked to the public world.
• On this view, surfaces without cores just don’t exist. And
(consequently) neither do surfaces without backs.
• On the other hand, if she begins to say that only facing surfaces
really exist, the new D.R. is on her way to phenomenalism.
• For Sellars this is just a mistake– we do not see ‘surfaces’ and infer
objects– we see objects, though what we see of them is just a facing
surface, we take it that there is an object and that it has a back (and
inner surfaces, if we should slice it) with some shape and colour too.
• Both the objects and the parts of them that we see can seem to be
other than they are: Illusion remains possible concerning them.
• But a second train of thought leads to phenomenalism: Here, what
is basically seen is a sense content; these are private, and not
subject to illusion– they are always as they seem to be to the
subject.
Retaining a key point
• Rejecting phenomenalism does not
require that we reject the existence of
phenomenal ‘colour expanses’ as
elements of visual experience.
• Sellars is persuaded that there are such
things, but that we need to locate them
very carefully in our conceptual scheme.
Phenomenalism: The slogan
• Physical objects are patterns of actual and possible sense contents.
• Taxonomy: Three traditions on the nature of sense contents.
• The first: Grounds its talk of sense contents in ordinary perceptual
talk: ‘directly sees’ and ‘directly sees that’ parallel normal use of
‘sees’ and ‘sees that’. So direct seeing involves knowing things
about what is directly seen.
• For example, the usual inference from ‘S saw an X’ to an X exists
carries over: ‘S directly saw a red triangular sense content’ implies
there was such a sense content.
• Further, just as objects can exist unsensed, this model allows (at
least in principle) that sense contents can also exist unsensed, and
just as objects can look other than they are, so can sense contents
(error is not ruled out). (Contra Berkeley here.)
• But of course direct seeings are seeings of sense contents, not of
public objects.
A second approach to
phenomenalism
• Links sense contents to conceptual thinking.
• This is where we get the esse is percipi notion: Just as,
for there to be an idea of x, someone must be thinking of
x, for there to be a red sense content, someone must be
having (perceiving) it.
• That some red triangular expanses (the sense-content
ones) must be perceived to exist does not mean that all
are like this– we can still have them ‘out there’ in the
physical world too.
• So it’s a further step to say (with Berkeley) that the real
red triangular expanses are all dependent on perception,
and that there are no independent ones at all.
Tangling the first two
• Someone who starts in the first way might still move on to claim that
for sense contents esse is percipi.
• But the argument she would need to make her case must either be
inductive (i.e. all the red triangles observed have been perceived, so
in general all existing red triangles must be perceived?) or synthetic
a priori (something about the idea of a red triangle demands a
subject who perceives it– this sounds rather like Berkeley…).
• On the second approach, though, ‘X is red’ outside of contexts of the
form ‘X is a red sense content’ is just ill-formed. This emphasizes
how far from our ordinary perceptual talk the second sort of theory
takes us.
• Further still: ‘X sees that’ has no parallel on the second approach–
there is no ‘X senses that’ here, just direct-object sensings of
various kinds of sense contents.
The third phenomenalism
• Here the beginning point is the link between sense content talk and
‘appears’ talk.
• So ‘S senses a red triangle’ doesn’t imply that there is a red triangle
(as with approach 2). (After all, that there appears to be a red
triangle does not imply that there is one!)
• We can get a form of the implication back by force.
• According to the third version, though, is that what we directly know
in sense perception is facts about sense contents, i.e. (on this
account) facts about how things appear to us.
• But this makes classical phenomenalism hard to accept, since it
puts ‘appears talk’ in its application to the physical world first, and
‘sense content talk’ is defined/understood in terms of a language
that apparently presupposes the categories of public physical
objects and their sensible properties.
A thesis
• Whenever there appears to S to be a red
triangular physical object somewhere, then it is
also true that S has a sensation of a red triangle.
• 3 gives us this by defining the second in terms of
the first. But a phenomenalist must find a
different route to this claim.
• Sellars also endorses the claim, but not in a way
that gives comfort to the phenomenalist.
• Sellars will defend a form of the second line on
sense contents.
A forced choice
• The phenomenalist has to choose
between a version of the second account
of sensations (one that doesn’t equate
sensations with ‘states produced ordinarily
by’ talk, which makes them dependent on
ordinary object talk), and the first (in which
sensations are perceived directly, and
such perceivings involve direct knowledge
of our sensations).
Esse is Percipi
• On the first approach, esse is percipi is not a
natural principle to adopt (since the model is
ordinary perceptual talk, and there what is
perceived can and does exist without being
perceived).
• It can be added by force, if a direct object
version of sensing (S senses x) is added, and
we assert that sensations only exist in such
relations to subjects. But we lose a direct link to
the cognitive side here; such relations might
exist, in principle, without S knowing anything
about the sensation S is having.
Towards a refutation
• The challenge to phenomenalism comes here.
• Recall that phenomenalism holds that ordinary objects
are (in fact) collections of actual and possible sense
contents.
• So we need to understand what ‘possible sense
contents’ are.
• The suggestion Sellars makes is that they are
possibilities that subjects are in a position to bring
about– analogous to skids that a driver is in a position to
bring about.
• So, for instance, when I have my eyes closed and I’m
standing in front of a white wall and it’s normally lit and I
can open my eyes, then there’s a possible white
sensation that I would have if I opened my eyes.
Justifying such claims
• To justify that sort of claim about what sensations I would
have if I were to do something, I need induction.
• This requires that I notice a regular pattern in my
sensations, of the form ‘Whenever circumstances are C
and I do A, E results’.
• We can think of many instances of such generalizations
where E describes sensations that I will have.
• But the standard cases are cases where C and A are
specified, not in terms of the sensations that I have or
had, but in terms of ordinary objects and
actions/movements that I make in public space (for
example, the fireplace on p. 79 or the white wall above).
A there pure phenomenal
generalizations?
• The circumstances and the action must be described in
phenomenal terms, not just the resulting sensations.
• But will the circumstances and the action be described
using actual sensations, or actual and possible (i.e.
conditional) sensations?
• On one hand, the phenomenalist has only claimed to
reduce objects & goings-on in the physical world to a
combination of actual and possible sensations.
• But on the other hand, if all the generalizations here
invoke both actual and possible sensations, how could
we ever have learned them? That is, what we learn
about the world depends on actual experience– possible
experience (whether phenomenal or not) makes no
impression on us and teaches us nothing.
Getting down to actual sensations
• So the challenge to the phenomenalist is
to frame generalizations that are pure, in
the sense that they are stated solely in
terms of actual sensations; only then could
we have inductive evidence of what
sensations are possible in a given (purely
phenomenally described) circumstance.
E and A generalizations
• Sellars allows that there really are some purely phenomenal
generalizations.
• But he distinguished between two kinds of such generalizations:
essentially autobiographical and accidentally autobiographical.
• The first are generalizations that we would normally explain as due
to the fact that, as individuals, we live among particular objects and
are subject to other particular ordinary object & perceptual facts
about ourselves. They cannot be separated from our
autobiographies.
• The second, however, though they are learned in the course of our
experience as individuals, hold independently of the particular
circumstances of individuals– only these could provide a general
account of ‘possible/conditional sensations’ in pure terms that would
support a phenomenalistic ‘reduction’ of ordinary objects to actual
and possible sensations.
Details on what generalizations are
needed
• …what the phenomenalist wants are
generalizations…which are accidentally
autobiographical, generalizations in which
the antecedent (circumstances C/
available/possible action A) serves to
guarantee not that I am in the presence of
this individual thing…but rather that my
circumstances of perception are of a
certain (general/sensation-only
dependent) kind. (83)
There’s more
• A lot has been granted that could be disputed here– the idea of
persons is also part of the ordinary object framework, and it too
needs to be reconstructed (ditto for their actions; the focus here has
been on the circumstances C).
• E generalizations ‘come with dirty hands’ (84), i.e. they hold only for
people in circumstances that are fixed in terms of the types of
objects present (including their sensible properties and
spatial/temporal arrangements).
• So they are not credible as unrestricted inductive generalizations–
which are what the phenomenalist really needs.
• There are real generalizations here- but they make the possible
sensations available to a subject dependent on the physical
circumstances of the subject. That is, they depend on the
framework of ordinary objects and our beliefs about how these
objects and the subject’s relations to them determine what
sensations the subject will have.
A hypothetico-deductive turn
• What is the hypothetico-deductive (HD) method?
• Theories are not arrived at by direct induction from our
observations– they are hypotheses which can
subsequently be tested by what they imply about our
observations.
• So the idea is that we form hypotheses and deduce
consequences for observations (Then we observe to see
if those consequences actually hold).
• Sellars’ argument to here has assumed a kind of
inductive basis for the bootstrap attempt to get ordinary
object concepts out of sensations.
• Maybe an HD approach can save phenomenalism!?!
What’s involved
• Neo-Lockean: Physical objects are part of a
theory that explains observed facts about our
sensations.
• No more ‘translation’ of physical object talk into
phenomenal talk.
• Nevertheless, theoretical entities (such as
ordinary objects) are still just that– purely
conceptual posits, intended to do the job of
organizing our observations. There is no need
to regard ordinary objects as anything more than
a convenient hypothesis.
Sellars’ response
• For Sellars, we should take theoretical entities seriously,
not dismiss them as mere ‘conceptual tools’.
• But this is not his reason for rejecting neophenomenalism.
• The relation between observation-language and theory
that HD requires is that inductively confirmed
generalizations in the observation language correspond,
via the bridge rules, to theorems in the theoretical
language (and no theorems should correspond to
disconfirmed inductive generalizations).
• But this breaks the proposal: Sellars’ earlier argument
against classical phenomenalism showed that there are
no such confirmed generalizations in the ‘language’ of
sense-contents.
Where from here?
• Return to direct realism: we directly see real
(public) objects, and in seeing them, we see that
they have various sensible properties (that is,
seeing in this sense is an epistemic/ knowledgeproducing/ judgment-involving act).
• No other form of knowledge is more basic. (This
is where our knowledge of the world begins.)
• But this does not mean that we don’t have direct
knowledge of other things.
• Including that we seem to see something/ and
features of our sensations/ visual impressions.
Direct?
• Direct knowledge is non-inferential– that is, we don’t
acquire it by reasoning from other things we know.
• But more: knowledge that p requires (on the point in
question) authorization, a right to be convinced that p.
• The inference schema for direct knowledge is: X’s
thought that-p occurred in manner M. So (probably) p.
• A label: This is trans-level inference, because it involves
a shift from the meta-level at which we talk of thoughts,
their contents, and the conditions in which they arise, to
the level of endorsing one of those thoughts.
• Care is needed to distinguish what is and is not directly
known in familiar cases of perception– the idea, for
Sellars, is to avoid representationalism. (=?)
Directness vs. Security
• There is a temptation to identify directness with security, and say
that we know more directly when there is less chance that we’re
wrong.
• Sellars rejects this– directness is a matter of whether nor not
inference is required. So, if I directly see a book and see of it that it
is red and rectangular ‘on the facing side’, that is direct knowledge of
the book. I might then infer that it’s also red and rectangular on the
hidden side, but that is not direct knowledge.
• But my knowledge that I’m seeing a book is less secure than my
knowledge that I seem to be seeing a book, though it is not any less
direct.
• Even if I sometimes do infer facts about what I’m seeing from facts
about how things appear to me, this doesn’t mean that all
knowledge about the physical objects I see is inferred in this way (in
fact, I learn to make claims about the sensible features of objects
around me directly long before I learn to talk about how things
appear to me.)
Parasitism
• In fact, Sellars claims that the “frameworks
of qualitative and existential appearings
and of sense impressions are parasitical
upon discourse concerning physical
things.”(89)
• The phenomenal world of these things and
their perceptible qualities does obey
regularities, and provides an observational
starting point for scientific theorizing.
Learning to perceive the world
• An abstractive account of concept-formation holds that we come by
concepts like red by means of experience of red things. (This
makes the notion that having the sensation of red is the key, and
even that the sensation of red is the ‘original’ from which the idea of
red is abstracted. See Hume!)
• Sellars claims instead that coming to have a perception of
something red as red, that is, a perception that involves the
judgment ‘this is red’, is not just a matter of having the relevant
sensation.
• It requires also a rich background of language learning and
dispositions to accurately report the colours of things and to
distinguish one colour from other colours, this thing from that thing,
etc.
• This logical space of things and their properties is ‘an evolutionary
development, culturally inherited.’ (90)
The process
• When I know something about an object by perceiving it,
there is a link between the object and my knowledge of
it: the sensation it causes in me.
• This sensation is what I respond to, but its effect is
causal– I don’t infer from facts I directly perceive about
my sensation to conclusions about its cause.
• Instead, my having the sensation is one causal factor
(another is my possessing the right conceptual
framework to respond correctly to the sensation in those
circumstances– itself a product of normal development
and language-learning) leading me to judge that some
claim about the perceptible qualities of the object is true.
A familiar idea, again
• Sense impressions are postulated, in order to explain
‘how things appear to us’.
• But for Sellars, if a theory is a good theory, we should
believe in the entities that theory posits.
• So for Sellars, there really are sense impressions.
• But they are not sense data, that is, they are not
cognitive states that form the premises on which our
‘theory’ of everyday things and their sensible properties
is built.
• Here we should pause to consider the pragmatic theory
of observation.
Learning the language of
sensations
• To learn to describe our sensations, both
we and our instructors must know
– How to report/ describe the sensible
properties of things in the physical world.
– How we describe sensations by analogical
use of these sensible properties.
• Then we can be trained to use ‘seems’ talk
and other ways of describing our
sensations, and even to report our
sensations directly.
Two links between sensations and
physical objects
• A sensation of a red triangle is a sensation that is
normally caused, under standard conditions, by the
presence of a red triangle before our eyes.
• Impressions of red/blue/yellow triangles resemble and
differ in ways analogous to the ways triangles that are
red/blue/yellow resemble and differ.
• The same goes for different shapes of a given colour.
• So we get families of predicates for properties of
sensations, each based on the predicates for the
corresponding sensible properties of physical things.
• Since these new predicates are predicates for features
of an episode (which is occurring in a person), i.e.
features of something that is going on, they are correctly
said to be adverbial. They pick out kinds of sensings.
But one more thing
• A theory aims to account for the inductively supported
generalizations belonging to some observation language.
• Why believe in its entities, if it’s really just used as a calculational
device to capture such generalizations?
• Sellars says, if the generalizations really hold up to the level of
‘epistemic variance’, then there really is no reason to take the theory
as more than this.
• But 1. We don’t really know the things of the MI exist, as we
conceive them in the MI.
• And 2. If they don’t, then there’s no guarantee that the laws of a
successful theory will correspond to inductively justified
generalizations in the MI.
• Instead, Sellars suggests that the SI will explain why the things of
the MI obey certain generalizations, to the extent that they do. No
strict generalizations cast in MI terms survive detailed careful
examination.
Towards Scientific Realism
• In principle, the SI could replace the MI in all its
uses, from observation to decision-making.
• But this is not the time: The MI provides a
constant background against which we can
check/compare the successes of scientific
theories. We don’t want to lock in a particular
‘body’ of scientific theory yet.
• But we still have some questions here. Just
what do we do with the (occurrent) properties of
physical objects, if we don’t think anything really
has them, but we describe our sensations in
terms of an analogy with them?
3 Stages
• 1. Nothing is really coloured (only public objects could
be, and they are not).
• 2. Sensations will persist, in some form, in the SI; but
we’ve said they have properties analogous to colour
(etc.). So colours in some sense may persist in the SI as
features of states of conscious, perceiving organisms.
• 3. Persons in the MI are single logical subjects.
Thoughts and sense impressions, in particular, are
attributed to a single subject. The framework in which
we think this way must be reconciled with a scientific
description of persons as complex structures built of
many separate parts.
The place of persons
• But because these complex structures think of
themselves as subjects, the single logical
subject, a person, is important in their thinking
and behaviour. (The neo-Hobbesian position
comes in here: 101f)
• This is no longer a matter of describing what a
person is, but instead a matter of identifying a
subject for normative purposes.
• To cope with sensations now, in our descriptive
theory, we need to separate them from the
grammatical subject (the I) who is said to have
them.
Counterparts
• When we think of two theories that aim to characterize the same
thing, we can think of the items/structures they each propose as
‘counterparts’.
• So here we’re concerned to identify the counterparts of sensations
as states of perceivers, in the scientific image.
• So where are these ‘sensa’? In the brain (i.e. where the relevant
physical events in the brain are occurring). When I seem to see a
red triangle, a ‘red-triangular’ sensum is occurring in some (visual)
region of my brain.
• They don’t seem to be in the brain, sure– but then, they don’t seem
at all– we don’t perceive brain events in propria persona, in fact, we
don’t really perceive them at all: these things are awarenesses (or
something like that…) not items we are aware of.
• Are we stuck with the primitive predicates of the MI? Clearly not.
Form must have content, but content comes in other varieties than
the familiar ones.
More on the SI view of ourselves
• Theories don’t get their meanings from the ‘observation language’;
they get meanings from applications & use. So the bridge laws (see
above) don’t work as partial definitions, leaving the rest of the
theory’s content ‘up for grabs’. They merely coordinate different
conceptual frameworks, and allow us to use our grasp of one to
learn to apply/use the other.
• The qualities of sensa may be found among the contents of a
scientific description of states that occur in the brains of organisms
like us.
• The scientific image converts us into complexes, multiplicities, even
though we think of ourselves as individuals. All the descriptive facts
about us must be re-framed to fit with this logical shift; the normative
view of things is something different, though.
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