
Please note:
This is an ancient (out of date) text version of a document originally written
in 1996 (posted to newsnet comp.ai.philosophy) then later copied here and
extended. The latest version can be found in
    http://www.cs.bham.ac.uk/research/projects/cogaff/misc/rock


                      WHAT IS IT LIKE TO BE A ROCK?

                              Aaron Sloman



                       School of Computer Science,
                      The University of Birmingham
                           Birmingham B15 2TT
                               England, UK

                         A.Sloman@cs.bham.ac.uk
                    http://www.cs.bham.ac.uk/~axs

Originally written Jan 1996
Added URLs 7 Jan 2009
Updated 15 Jul 2014:
    Added References to Parametric polymorphism and Virtual Machine
    Functionalism (Sloman and Chrisley 2003) 15 Jul 2014

                                ABSTRACT

This paper aims to replace deep sounding unanswerable, time-wasting
pseudo-questions which are often posed in the context of attacking some
version of the strong AI thesis, with deep, discovery-driving, real
questions about the nature and content of internal states of intelligent
agents of various kinds. In particular the question 'What is it like to
be an X?' is often thought to identify a type of phenomenon for which no
physical conditions can be sufficient, and which cannot be replicated in
computer-based agents. This paper tries to separate out (a) aspects of
the question that are important and provide part of the objective
characterisation of the states, or capabilities of an agent, and which
help to define the ontology that is to be implemented in modelling such
an agent, from (b) aspects that are incoherent.

The paper supports a philosophical position that is anti-reductionist
without being dualist or mystical.



INTRODUCTION
Discussions of consciousness, including whether machines can be
conscious, which animals are conscious, how consciousness evolved, what
the function of consciousness is, etc. are often based on the assumption
that we all know what we mean by the word "consciousness". Moreover,
it is assumed that what we mean can be identified by various words and
phrases which are part of common usage, but which become elevated to
pseudo technical terms for the purpose of bolstering philosophical or
scientific discussions of consciousness. A much discussed example
is this form of phrase: "What it is like to be an X?" (Nagel 1981).
This recurs often, for example, in discussions in the comp.ai.philosophy
newsgroup.

My own belief is that much discussion of consciousness is based on a
highly inflated conception of the clarity of the questions being posed,
and the objective of this paper is to deflate such discussions. I don't
deny that there are questions to be asked, but I claim that
we need a new route to such questions, based on architectures for
various kinds of intelligent agents, and analysis of the sorts of states
and processes various architectures can support.

Unfortunately, the temptation to ask pseudo-questions remains very
strong. The purpose of this paper is to help to reduce that temptation.
It will not work for all readers.

STRATEGY

My strategy is in part to consider this question

What's it like to wonder what it's like to be an X?

I shall attempt to analyse what sorts of requirements there are for
satisfactory answers, by considering a range of cases, from several
viewpoints, and then end with a philosophical position
which is both anti-reductionist and functionalist.

What is it like to be that rock over there?
-------------------------------------------

Well, I don't know the whole answer, but, unlike the rock, I know a lot
of it.

It is like being about a foot in diameter.

It's like weighing a few pounds.

It is like being made mostly of silicon (I think).

It is like resting on a muddy patch of earth with a slight slope.

It's sometimes like being pushed around, thrown up into the air, and
falling to earth with a thud.

But never like knowing any of this is happening.

Some will object that I've distorted the question, for I've
wrongly taken "What is it like to be X?" to ask only:
"What is X like?" The former presupposes that X has a point of view
and requests a description from X's point of view, whereas the latter
does not require X to have a point of view. Of course that merely shifts
our problem: what is a point of view, and which sorts of things have
them? Does a sunflower have a point of view?


What is it like to be a sunflower?
----------------------------------

I don't know as much about this, as about what it's like to be a rock.

It's like being able to grow bigger and being able to produce roots to
find nourishment and support.

But not like being able to walk or run.

It's like having information about which way up is and the direction of
the sun, but not information about very much else, at least in the
environment.

Nor can the sunflower do very much with the information that is
available to it. For example, it's not like being able to use the
position of the sun to decide that it's time for the children to go to
school.

Neither does being like a sunflower include knowing very much about the
differences between up and down, or the differences between the sun and
the moon, or why it might be useful to keep facing the sun.

It has a viewpoint in the sense that a viewpoint is a
location in the world which provides information about the
world. Different information is obtainable from different viewpoints.
But the question is not just about the physical or geometric properties
of the viewpoint, but also about what information the sunflower (or
whatever we are talking about) actually acquires and uses, and how it
uses it. That's a topic for biologists to investigate. It may be
difficult, and our knowledge at present is only partial, but it involves
no intrinsic mystery.


What is it like to be a bat?
----------------------------

That's probably much more fun - whizzing about at high speed, even in
the dark.

A bit like being on a roller coaster, but much more in control. E.g.
rapid changes of direction will cause rapid shifts in the magnitudes
and directions of inertial forces to be detected and overcome.

It's a bit like being able to make and hear sounds too high pitched for
human ears. But it's not much like being able to sing a Mozart soprano
part or enjoy hearing one.

It's like hearing how far away something is, but not
like hearing how big a room is by clapping hands.

It's sometimes like hanging upside down for long periods but without
experiencing torture.

There's much more we can say about what it's like to be a bat than what
it's like to be a sunflower, because a bat does far more, and also
because it is far more like us, which tempts us to extrapolate and use
our own descriptive categories.

On the other hand, what it's like to acquire, process, store, or use
information as a bat does is not something we can hope to
understand in any detail -- for the bat does not use anything like our
conceptual apparatus, as far as I know. This is a point Nagel makes,
though he gives no explanation.

The explanation may be that the information processing media and
mechanisms used by the bat have different structures and possible
transformations from ours, and there are no ways of mapping its states
and processes into ours without serious distortion of the structures and
relationships.

There may be some small overlaps, e.g. to do with the bat's and our
ability to cope with space, and time and motion, but these are embedded
in very different webs of relationships to other things, for instance
the shape of an attractive mate, or tempting morsel.

Its world is not our world, and there's no reason to believe that its
categorisations of things, states, events, processes, actions,
or whatever replaces such things in its control mechanisms, will
map in any straightforward way onto the categorisations we use.

In short, to misquote Wittgenstein, if the bat could tell us what it is
like to be a bat we would not understand it.

There are at least two different reasons for this: first its
requirements and its relations to the environment are very different
from ours (we don't often fly through the air chasing and eating
fluttering moths), and secondly its processing engine may be different
from ours in subtle ways. For instance, it may be wholly incapable of
being in as many different types of states, and it may not have the same
variety of functionally distinct, coexisting, interacting components.

Its representational grammars are different, and hence their semantic
capabilities are different. (Cf. Sloman 1994, Wright et al 1996).

Some languages cannot be learnt if you don't have the right sort of
engine to run them on. Obviously a simple information processing engine
may be incapable of replicating semantic states of more complex ones.
The converse is less obvious, but can also be true.

Despite the impossibility of translating bat information states
into our own there is nothing, in principle, to stop us producing fairly
detailed descriptions of the kinds of structures and transformations of
such states. For example, we might discover that its sound-processing
capabilities allow it to produce information states that can vary in 17
dimensions, or that its representations of the structures of other bats
distinguish 37 bat components and use 5 types of relationships between
those components.

A full theory of bat semantics might require is to extend our logical
metalanguage, however: maybe bat cognition does not use objects,
properties and relationships, but only interactions between attractors
in phase spaces. (Cf. Cohen  Stewart 1994, Sloman 1995)

Of course, discovering such things may be extremely difficult. Moreover,
although it would give us a partial answer to the question "What is it
like to be a bat?" it will not enable us to experience bat-like
states. You cannot necessarily experience, or even imagine experiencing,
everything you can describe, for instance, being a sixteen dimensional
dancer in a forest of nineteen dimensional shapes.

This is perhaps an explication of the possibility Nagel raises towards
the end of his article, of an objective description of subjective
states. Note that such objective descriptions need not be descriptions
in the language of physics. They are more likely to be descriptions in
the language of linguists and computer scientists, who talk about the
properties of information structures independently of their
implementation, even though the implementation is always physical.

What's it like to be a (normal) new-born human infant?
------------------------------------------------------

It's like being simultaneously too weak, too uncoordinated and too
ill-informed to be able to cook your own supper.

But it's not like knowing you are all those things, for the infant
(probably) knows nothing about being weak, coordinated or informed, or
about cooking or supper.

It's a bit like being able to see, to hear, to feel hunger and pain,
though via processes that do not make use of typical adult human
concepts and which we are therefore currently unable to describe in
detail. If a neonate could talk, we'd understand only a little more than
if the bat spoke. (As puzzled parents will confirm.)

One of the striking features of the human mind is that it changes. Many
of the changes may seem gradual at the time, but the cumulative effects
can include major discontinuities, including the creation of new
information structures (e.g. learning about quantum mechanics) and new
control architectures (e.g. becoming able to postpone gratification). We
know very little about such developments, not even how much is
pre-programmed genetically and how much driven by interaction with the
environment. Certainly the environment plays an important part, since
not everyone learns to speak Chinese, or read music, or grasp quantum
physics.

So there's enough diversity in adult human information states to make
full translation between them impossible. The difference between what I
can know of what it's like to be a bat, and what it's like to be you is
only a difference of degree.

Not all the development is growth or improvement, alas.

What's it like to be in the advanced stages of Altzheimer's disease?
--------------------------------------------------------------------

This something about which I know very little apart from the sort of
thing picked up by watching a sad and moving television documentary.

For example, in some cases it's apparently like wanting to dust a
window-ledge without remembering that you have dusted it already a
minute or two before.


What's it like to be autistic?
------------------------------

I recently (November or December 1995) watched the second half of a
spellbinding television program (UK TV Channel 4 I think) about an
autistic woman who had become very articulate and had written a book.
It's very clear that what it's like to be her is somewhat different from
what it's like to be a 'normal' person.

Sloman (1989) referring to (Selfe 1977), available here:
http://www.cs.bham.ac.uk/research/projects/cogaff/81-95.html#7
conjectures that the spectacular drawing ability of Nadia, an autistic
child, might be a result of abnormal concentration of processing
resources on low level image analysis and interpretation because higher
level integrative and interpretative mechanisms which would dominate
normal vision were non-functioning for some reason.

If so, processes that in normal brains work to minimise or cut
short low level analysis and interpretation, for the sake of speedy
high level recognition and decision-making, are not available in some
autistic brains. So the low level processing dominates, and the higher
level more abstract and holistic interpretations therefore do not occur,
or are simplified.

The autistic woman tried to describe her experiences shopping in
a supermarket, and various camera tricks attempted to give the viewer a
taste of what it was like: lots of small scale, low level, rapidly
changing detail, from which it was hard to synthesise an overview. Of
course, a normal person would get an overview such as I've just
described, but that is not the same as getting an integrated visual
overview. Camera tricks probably don't actually convey
what it's like to be autistic: they merely change the high level
synoptic characterisation, without suppressing it altogether.

So here's another case where we may be able to go a long way towards
describing the nature of a (partly) alien form of experience, while
being incapable of having or imagining that experience. Description is
always easier than replication.

A person who is not autistic could get quite a lot of information about
what it's like to be autistic by watching the film. In fact I found that
her unusual use of language and explanatory constructs and illustrative
models (moving toy animals around on a table top) temporarily changed me
in a strange way while I was listening to her -- a reaction
to the extraordinary mixture of familiar and unfamiliar features of both
her way of speaking and the content of what she said. But most of what I
got was description, not replication, of her experiences.


What is it like to be a seer?
-----------------------------

You don't need to be like X to know a lot about what it's like. A
congenitally blind person can know a lot about what it's like to see.

It's like getting information about the surfaces of things -- their
textures, orientations, locations in space -- but without touching them.

Also it's more parallel than the serial exploration of the outside of an
elephant with your hands. It's more like simultaneously exploring the
whole shape of a cup with several fingers on two hands, but not
including the 'far' surfaces.

Much of the information obtained by visual and tactile perception is the
same, though there are subtle differences in its availability for
various uses: e.g. rapid comparison of two faces, or searching for a
family resemblance. If I could only see my bow arm moving, and not also
feel it, the sound of my violin would be even worse.

Seeing colours is often very like detecting the textures on surfaces -
there are colour and texture regions, colour and texture boundaries,
colour and texture gradations, colour and texture composition, 2-D
shapes such as letters or polygons made by regions of a common texture
or colour, etc.

What it's like to see colours is partly like getting all that surface
information very rapidly and at a distance, and also having it presented
to you in a spatially structured way (i.e. not as a long list of
sentences).

What does that leave out? Well, quite a lot, and I could describe some
of it in terms that a sighted reader would understand but a blind person
might find difficult.

On the other hand, we should remember that a congenitally blind person
whose eyes have never worked may still have a lot of the brain
mechanisms used by the rest of us in seeing colours, developed in a
shared evolutionary history. Perhaps such a person can use some sort
of abductive inference from hearing other people talk about colours and
other spatial properties, and this might recreate similar structures to
those used by sighted people in comprehending talk about colours. The
important point is that it's an empirical question what a
congenitally blind person is capable of understanding. And that depends
on what information processing capabilities are in his brain.

Blind people given a stylus with a hot pointed tip for drawing on
plastic can produce pictures with some of the structure, e.g. the
topology, of pictures drawn by sighted adults. However, angles and other
relatively global metrical properties are different. That's also
true of pictures drawn by young children whose vision is perfectly
normal.

It might be true of a robot whose visual system is designed to give it
information about 3-D structures in the environment, not about the 2-D
structure of the optic array at a viewpoint. The fact that that 2-D
structure is there in its visual system and is used by low level visual
procedures does not mean that the robot can consciously access it or use
the information to produce an external 2-D drawing. What it's like to be
that robot could include inducing 3-D structure from various
intermediate 2-D shapes, without knowing anything about the 2-D shapes,
just as we are ignorant of the vast majority of what's in our own minds.

What it's like to be able to see is not necessarily what it's like to be
able to draw what one sees. The information processing requirements are
very different. Similarly, being able to see need not involve the
ability later on to recreate accurately a detailed internal replica of
the experience. When we remember seeing things normally only a small
subset of the original state is reproduced (though some people, like
Nadia, can store and reconstruct more details than others).


What is it like to be a woman?
------------------------------

No doubt there's a lot I'll never know. I know what it's like to find a
woman sexually attractive, and on the basis of that I think I know at
least some of what it's like to find a man sexually attractive, but not
all. So perhaps I know more about what it's like to be a lesbian than a
'straight' woman.

I don't have direct experience of feeling 'broody', i.e. desperately
wanting to produce a child, but I know quite a lot about what it's like,
from talking to some who have. I think I know what it's like to be
consciously or unconsciously discriminated against or patronised, in a
male dominated society, though I have not had that sort of experience
myself.

Besides common differences between infants and adults, between brain
damaged or senile individuals and those who are still functioning
normally, there may also be deep and subtle differences in cognitive
functioning between adults, based on genetically determined
differences in information processing mechanisms in their brains.

Whether this is so or not, and whether it explains such things as the
rarity of musical or artistic or scientific genius, it is clear that
there are some differences that are related to gender, and for good
reasons: without them the gene complexes constituting human beings would
be much less successful at replicating themselves. (Some would argue
that at present they are far too successful either for their own good or
the good of other organisms, and a change is long overdue.) Thus an
intelligent robot could not simultaneously be exactly like a woman and
like a man.


What is it like to be a robot?
------------------------------

Obviously it's going to depend a lot on the type of robot.

A robot that has only a tiny fraction of our bodily sensors will never
have the full and rich experience of riding in a roller coaster, feeling
all the centrifugal and gravitational forces, feeling the rush of wind
on face and in hair, hearing all the screams, feeling the closeness of
the excited and terrified child clinging to it, or the dryness of the
mouth that can go with one's own terror.

But it might know a lot about what it's like for human roller coaster
riders, by using what it knows about the whole situation and about human
sensory capabilities, motivation, emotional states, etc. In other words,
it may have a great deal of knowledge about the information processing
capabilities, the forms of representation, and the cognitive functions
of human beings, even if it is not able to replicate most of them within
itself.

So what it's like to be a sophisticated robot with a body very different
from ours might include knowing quite a lot about what it's like to be a
human being, though not everything. The robot could well know a lot more
about what it's like to be a human being than what it's like to be a
bat, and for exactly the same reasons as our batty knowledge is limited:

    (a) lack of information

    (b) wrong conceptual apparatus to be able to replicate bat-like
        information processing.

It's often claimed (by Nagel, and many others) that a robot might
simulate many of the behavioural capabilities of a human being without
having anything remotely like the conscious states of a human being, or
a bat, i.e. without there being anything that it is like to be the
robot.

But this ignores the fact that a robot of the sort in question
could not function without sophisticated information processing
mechanisms, and we can then ask questions about the internal states
and processes concerned with the information processing level (Sloman
1994) which are not questions about its physical state. We can ask
what information it has about various objects in the environment, or
about itself, or about its own internal states (McCarthy 1995).

Some robot states we may be unable to replicate in ourselves, as with
bat states. But we may nevertheless be able to describe them, that is
describe their structures, their semantic contents, their
transformations, and the uses to which they are put. Any such
information processing system will necessarily have as much of a
viewpoint as you or I, or a bat. Whether we can experience the same
viewpoint or not, we can talk about it and the role it plays in enabling
the system to function.

There is no reason to suppose that such a properly functioning
robot could be a 'zombie', defined as something that merely produces
behaviour without having any experiences, viewpoint, or something it's
like to be. People who claim they can imagine such a thing are deluding
themselves, like people who think they can imagine a method of
accurately trisecting any angle using only ruler and compasses. They
lack adequate training (in this case engineering training): such a robot
could not work.

Note: Some time after after I wrote the above, I learnt about the 'neusis'
construction, which makes trisection of an arbitrary angle easy, by changing the
function of the ruler (sraight edge).
http://www.cs.bham.ac.uk/research/projects/cogaff/misc/trisect.html

For a good engineer to imagine a zombie robot she has to turn off what
she knows about what enables the robot to process perceptual
information, to acquire new goals, to select between goals, to be
inclined to continue with some activities and desist from others, to
detect achievement of its goals, or cope with unexpected and sudden
external disruption.

I am making strong claims about the high level information-processing
ontology of any system with human-like intelligence. But I need to be
careful: it may be theoretically possible to have a huge lookup table in
which all possible sequences of sensory input have been previously
stored and appropriate external responses provided. If this were
physically possible (which it isn't for most human-like capabilities),
then such a machine would not require a human like internal ontology. It
would be much more like a rock than like a bat. If you want to imagine a
zombie, you had better design one that could work, as I've just done.

(It follows from the above that feeding a design through a heavily
optimising compiler that unfolds loops and conditionals and flattens
subroutine calls, could produce a zombie implementation,
indistinguishable externally from a sentient, thoughtful robot. In this
sense implementation can matter.)

PRELIMINARY CONCLUSION

I have tried to show, by considering different cases, that there are
many things we can know about what it is like to be an X, and things we
cannot, and the reasons are different in different cases. There is no
one deep philosophical reason. However, some aspects of what it is like
to be an X cannot always be replicated in a Y, where Y has a different
information processing architecture. When understood right that's a
theorem of information science, not a philosophical problem!

SOME PHILOSOPHICAL OBJECTIONS
Many philosophers will agree with all that. But, some philosophers (and
some non-philosophers) will protest, none of this adds up to
telling me what it is like to be an X, FROM THE INSIDE.

It's not at all clear what sense the capitalised words add, or whether
there is any coherent sense that they add. They do make some sense,
which I'll now explain. But some people will feel I've still left
something out. I'll offer them therapy later.

I can certainly talk about what it is like to be you, located where you
are, seeing things that only you can see, feeling things which I don't
(e.g. because you are sitting in a comfortable armchair and I am
squatting on the floor), and knowing things about your own state of mind
which I can at best guess.

If what it's like to be you 'from the inside' means something about what
it's like to have your view of the world, including your view of the
current state of your own mind and body, then I can't know exactly what
it's like to be you because I lack much of the information.

Some of it I may be able to work out. I infer that you see
part of that wall which a large pillar obscures from me, and I can also
work out that you know whether my remark really made you angry or
whether you are just teasing me. You know, but I don't, but I know that
you do.

There's no huge difference between knowing that there's something
outside you to which you have access I lack and knowing that there's
something inside you to which you have access which I lack. Both cases
involve differences of access to information.

Of course, I can remove one of the differences by walking round to where
you are, and then I'll see the previously invisible part of the wall.

But I can't walk round to a place where I'll have your view of your
current emotional state.

Moreover, if you are colour blind and I am not, or vice versa, I won't
even have exactly your view of the fresco.

Maybe one day, a pair of special helmets, linked by optic fibres, may
overcome this obstacle to sharing your viewpoint, just as my walking
closer to you, or using appropriately placed mirrors and cameras can
overcome some of the lesser obstacles.

Whether such a helmet is possible is an empirical issue: there's nothing
philosophically deep about it. (Not as deep perhaps as the difficulty of
knowing what's going on inside subatomic particles, or whether 'inside'
even makes sense in their case: now there's a hard problem if you want
one.)

DO COMPUTERS HAVE A POINT OF VIEW?
Currently, computing systems are very different from ourselves. They
don't have anything like our information processing architecture -- for
instance, their long term memories function in very different ways (the
problems of acquiring, accessing and forgetting things are totally
different). They (mostly) lack anything remotely like human motivation,
and those that do have goal processing capabilities generally get their
goals from someone else, whereas human beings contain multiple
independent sources of motivation which (generally) do not subserve
anyone else's goals. (Human motive generators do not always subserve the
individual's goals, interests or needs, for instance if the generators
were selected by evolution because of their contribution to promotion
and survival of the gene pool. Our genes would laugh at us for some of
the things they make us do, if genes could laugh.)

Because of these differences between computing systems and people (or
other animals), our knowledge of what it's like to be a time-shared
computing system is not all that different from our knowledge of what
it's like to be a rock: it's mostly "third person" information about
what's going on, and perhaps only a little less boring.

However, as AI systems get more and more sophisticated with more and
more autonomy both in motivational mechanisms but also in development of
conceptual apparatus controlling perceptual processes and determining
the semantics of internal information stores, then there will be more
and more questions we can ask about what it's like to be such a system
'from its viewpoint', e.g. what sorts of things can it see in various
situations, what sorts of things does it want to do in various
situations, what sorts of decisions does it face, what does it find easy
or difficult, pleasant or unpleasant, etc.

I.e. there will be more and more about what it's like to be that sort of
robot FROM THE INSIDE.

Whatever that means.

Of course this will take a long time -- maybe hundreds of years before
they get to chimp-like ways of being and still longer before they reach
human-like states.

When that happens, some of the robots will start wondering what it's
like to be a person, or a bat. Or maybe even a rock.

MORE PHILOSOPHICAL OBJECTIONS

    "BUT...." splutters the frustrated objector, growing ever more
    exasperated with me, "You still have not got around to what I was
    talking about: what it's REALLY like FROM THE INSIDE to be a bat or a
    person. All you are talking about is what it's like to have a variety of
    physical properties and states and processes and also some non-physical
    (though physically implemented) information processing capabilities and
    states and processes.

   "That's not what I was referring to in talking about what it's like
    to be X. The things you are referring to are all things for which
    there might be objective evidence, e.g. evidence from X's
    relationship to things in the environment (determining which things
    are not currently visible to him), or evidence from what the
    designer knows about X's high level functional architecture
    (determining which kinds of visual processing, memory processes,
    goal generation, planning, reasoning, forgetting, etc. etc. can
    occur in X).

   "I am talking about the INTRINSIC quality of what it's like to be X,
    which cannot be inferred from these things.

    "E.g. two sub-aspects of what it's like to be X (in my sense) might
    be swapped without this having any externally detectable effects or
    causes, and without it making any difference to the functional
    capabilities to see, reason, plan take decisions, etc. For instance,
    what it's like to see the colour of the sky and what it's like to see
    the colour of grass might be swapped in X, and everything else could
    remain the same. X could tell us that something strange had
    happened, and that sky and grass each now looked the colour the
    other used to look. But he could not tell us what that colour was.
    He'd have no way of telling, for example, whether his new view of
    coloured things was the same as other people's or his old view, or
    neither."


Let's be clear about this: some of what's being said here is OK and some
not. The interplay between the two is very subtle and it is difficult to
separate them. But we must separate them to clarify requirements for the
design of a human-like intelligent agent. Human like, non-zombie robots
should be capable of experiencing Necker flips.

FLIPPING QUALIA

Consider what happens when you look at a Necker cube: suddenly it flips,
and although the retinal image and visible 2-D structure are unchanged,
the 3-D interpretation is different. Lines, or rather cube-edges, that
once sloped down away from the viewer now slope up away from the viewer,
and the vertical square cube face that was previously further away is
now nearer. Perhaps there could be a sort of Necker flip of colours,
with visible sub-regions switching how they look, just as parts of the
cube switch (some aspects of) how they look?

Whether this is possible is an empirical question.

In the case of the cube nobody (so far) has claimed that the switch is
undetectable from outside and indescribable to others. Indeed brain
scientists may one day find out exactly what sorts of neural processes
are involved in the flip from one state to another, and may even be able
to create non-invasive mechanisms for detecting the occurrence of such a
flip.

Moreover, it is more than likely that one day robot vision systems will
be capable of such flips: in fact requirements for normal vision include
the ability to handle locally ambiguous fragments of images which can
have different interpretations fitting into different coherent global
scenes. (What is seen as a leg in one context may be seen as an arm in
another).

So the Necker flip in what it's like to see the pattern of lines as a
cube is (a) part of the expected behaviour of functional components of a
visual architecture, (b) capable of being explained in terms of
underlying neural or computational mechanisms, (c) capable of being
detected from outside (at least in principle), (d) capable of being
described (in terms of changing geometric relations between parts of the
cube), (e) likely to occur in visually sophisticated robots, under
appropriate conditions.

Could there be flips in how colours appear too?

How you see the colour of a portion of a surface of an object can change
according to the context, as shown by a variety of visual so-called
"illusions", including for example the Kanizsa figures in which we see
colour boundaries on a uniform surface. Another case is an array of
black squares on a white ground, in which we see dark patches between
the squares, which disappear when we look directly at them. Perhaps
there are some experimental situations to be discovered at some time in
the distant future, in which everything that now looks green suddenly
looks red and vice versa, and this will be explained as part of a
natural side effect of how a fully functioning visual system implemented
in a certain way works.

Such a colour flip might have all the features (a) to (e) that the
Necker cube flip has.

But none of that fits the intended philosophically puzzling situation:
for there the alleged logically possible flip is supposed to be totally
unrelated to anything functional, incapable of being explained in terms
of underlying mechanisms, incapable of occurring in any robot, incapable
of being detected from the outside, and incapable of being described.

At this stage we (or rather our worried friends) have
begun to reach one of those ancient philosophical traps: words and
phrases which sound as if they are saying something clear, and rich, and
fascinating, but which say nothing at all.

Or rather they say nothing capable of being the content of a true or
false assertion or a question with right and wrong answers.

SEMANTIC TRAPS
Here are some old, well-known examples, of how one might fall into such
traps:

   "Clearly it's (logically) possible for this cup to move a foot to the
    east, and then my spectacles to move a foot to the east, and then
    the table, and then the house, and then the earth and then the sun
    and then the rest of the solar system, and, and, and ... until
    everything in the whole universe has moved a foot to the east.
    (There might have to be some temporary changes in the laws of
    physics while these various steps occur, but that's also logically
    possible.) And at the end of such a process EVERYTHING in the whole
    universe would have moved a foot to the east, but that new situation
    would be TOTALLY indistinguishable from the original state.

    "So how can we be sure it hasn't happened, and our memories
    tampered with so that we don't remember any of our changes? And
    maybe it's happening all the time, with everything slowly moving
    to the east, but no motion detectable because all the measuring
    instruments are also moving, and the laws of physics have been
    carefully adjusted to ensure that no experiment will reveal the
    motion. (Compare the Michaelson Morley experiment which failed to
    detect which way the earth was moving through the 'aether'.)"


If you really think the hypothesis just described makes sense, and that
there may be motion of the whole universe that's totally undetectable,
then you may as well stop reading, for I have no way of convincing you
that you are deluding yourself. You need stronger therapy than I can
offer.

It's one of the features of being like a human that such delusions can
be very tempting, and in some cases incurable. Similarly, if you are
tempted to wonder whether it really is noon at the centre of the moon
when the moon is directly above Greenwich and it's noon at Greenwich,
then that temptation may be incurable, no matter how much I try to
convince you that the question is too ill-defined to have an answer, any
more than the question whether the number nine is green or yellow.

The notion that the colour experiences you have when looking at grass
and sky might suddenly be swapped in such a way that absolutely
everything else, or everything else that someone else could observe,
measure, control, etc. remains the same, is as coherent as the
notion that this change is happening all the time, only you don't notice
because your memory is constantly being fixed so that you forget what
the colours really were like.

And that's as coherent as the notion that all sorts of pairs of
experiences are CONTINUALLY being swapped in such a way as to be totally
undetectable by you and in such a way as to preserve all functioning
aspects of the system.

And that's as coherent as the question whether the universe is
constantly moving to the east, or the north, or the north north west, at
three miles per hour, or three cm per hour, or at any other speed, but
in such a way that the motion cannot be detected. See (Dennett 1991) for
related arguments.

Note added 15 Jul 2014
    Sloman and Chrisley, 2003, present an explanation of how concepts
    generated within a self-organising classifier, that is part of a
    self-monitoring virtual machine, may exhibit "causal indexicality",
    making them untranslatable into concepts used by anything else.
    They will have a kind of logical privacy that Wittgenstein did not
    imagine was possible. Online at:
    http://www.cs.bham.ac.uk/research/projects/cogaff/03.html#200302

INCOHERENCE IS NOT THE SAME AS LACK OF MEANING

Of course these words and phrases are not MEANINGLESS. They
*resonate* with rich meanings. The semantics of the components
combine to form a rich structure, which drives many of the processes of
reasoning, question formation, wondering whether, and the like which are
the very stuff of cognition in science and everyday life and philosophy.

But they may still fail to add up to anything with the properties
required of a serious question or hypothesis, much as the fragments of
the image of an impossible Penrose triangle all make sense, and globally
they make a kind of sense, but fail to add up to a possible continuous,
straight-edged, 3-D object. In the case of the triangle most people can
see the impossibility fairly quickly. But when it comes to an impossible
hexagon or an impossible 63 sided object, constructed in the same way,
no human will be able to see the impossibility without very laborious
checking. It will simply look like a complex 3-D object, especially if
it is not presented as a regular polygon.

Similarly lots of people fail to see the incoherence of many of their
philosophical questions and descriptions of allegedly possible
scenarios.

Similar things underlie religions and many superstitions.

CONCLUSION

Asking what it's like to be an X, when taken seriously, so that we
knuckle down and try to work out detailed answers, can be part of the
process of uncovering some of the internal ontology, the virtual machine
requirements, the abstract data-types and operations on them, which we
need to think about if we are to design human like systems, whether as
engineers building new slaves or playmates, or as scientists trying to
understand by designing and implementing. So, far from being part of an
anti-AI activity it is a necessary part of AI in the long run. (How to
do it is another question, for another day.)

Of course, many philosophers will be unmoved by all this. They will
accuse me of being a crude empiricist, a verificationist, an out of date
positivist, a science worshipper, a zombie in disguise, a
zombie-promoter, a heathen, a liar ("feigning anaesthesia", as one
philosopher once put it), or worse.

And there's nothing I can do to prove them wrong. For when the human
brain gets trapped into the state of believing that certain kinds of
grammatically well formed sentences actually mean something to it,
there's no rational argument that can change the situation. Sometimes
long term philosophical therapy works, and sometimes it doesn't.

I say all this because I know what its like to think one understands
what one is saying when one puts forward those arguments and asks those
questions. I know what it's like to be there. I've been there.

REFERENCES

Paco Calvo, 2017,
What Is It Like to Be a Plant?,
Journal of Consciousness Studies
24, 9-10, pp. 205-227,
http://www.ingentaconnect.com/content/imp/jcs/2017/00000024/F0020009/art00012

J. Cohen and I. Stewart The collapse of chaos,
Penguin Books, New York, 1994.

D. C. Dennett,
Consciousness Explained
Penguin Press,
Allen Lane, 1991,

J. McCarthy,
Making robots conscious of their mental states,
AAAI Spring Symposium on Representing Mental States and
        Mechanisms Stanford, 1995,
Accessible via http://www-formal.stanford.edu/jmc/

Thomas Nagel
What is it like to be a bat, in
The mind's I: Fantasies and Reflections on Self and Soul
Eds D.R. Hofstadter and D.C.Dennett
Penguin Books 1981, pp391--403
(Followed by commentary by D.R.Hofstadter, pp403--414.)

Lorna Selfe,
Nadia: a case of extraordinary drawing ability in an autistic child
London, Academic Press, 1977.

A. Sloman,
'On designing a visual system: Towards a Gibsonian computational model
of vision' Journal of Experimental and Theoretical AI
1,4, 289-337 1989
http://www.cs.bham.ac.uk/research/projects/cogaff/81-95.html#7

A. Sloman,
'The mind as a control system', in
Philosophy and the Cognitive Sciences,
(eds) C. Hookway and D. Peterson,
Cambridge University Press, pp 69-110, 1993
(Supplement to Philosophy)
http://www.cs.bham.ac.uk/research/projects/cogaff/81-95.html#18

A. Sloman, (1994)
Semantics in an intelligent control system, in
Proc. British Academy and Royal Society Conference:
Artificial Intelligence and The Mind: New Breakthroughs Or Dead Ends? in
Philosophical Transactions of the Royal Society: Physical Sciences
and Engineering,
Vol 349, 1689, pp 43-58 1994
http://www.cs.bham.ac.uk/research/projects/cogaff/81-95.html#25

A. Sloman, (1995)
Musings on the roles of logical and non-logical representations in intelligence,
in Janice Glasgow, Hari Narayanan, Chandrasekaran, (eds),
Diagrammatic Reasoning: Computational and
Cognitive Perspectives, MIT Press, 7--33
http://www.cs.bham.ac.uk/research/projects/cogaff/81-95.html#33

[Added 15 Jul 2014]
A. Sloman and R.L. Chrisley, (2003),
Virtual machines and consciousness,
Journal of Consciousness Studies, 10, 4-5, pp. 113--172,
http://www.cs.bham.ac.uk/research/projects/cogaff/03.html#200302

I.P. Wright, A. Sloman and L.P. Beaudoin, (1996)
Towards a Design-Based Analysis of Emotional Episodes, in
Philosophy Psychiatry and Psychology,
Vol 3, no 2, pp. 101--126.
http://www.cs.bham.ac.uk/research/projects/cogaff/96-99.html#2

See also
    Virtual Machine Functionalism
    (The only form of functionalism worth taking seriously
    in Philosophy of Mind)
    http://www.cs.bham.ac.uk/research/projects/cogaff/misc/vm-functionalism.html


[Added 15 Jul 2014]
A. Sloman (2011, modified 2014)
Family Resemblance vs. Polymorphism
 A comparison: Wittgenstein's Family Resemblance Theory
    vs. Ryle's Polymorphism
    and Computer Science/Mathematics Polymorphism
  http://www.cs.bham.ac.uk/research/projects/cogaff/misc/family-resemblance-vs-polymorphism.html
  http://www.cs.bham.ac.uk/research/projects/cogaff/misc/family-resemblance-vs-polymorphism.pdf
