I’ve had a few additional thoughts further to my recent
post on counting
conscious states, particularly on the extent to which a given conscious
state is history-dependent (i.e., depends on its history of prior conscious
states) and whether a particular conscious state can be created *de novo*
(i.e., from scratch, without the person experiencing that state having actually
experienced previous conscious states).

Imagine that a person has actually experienced a particular
series of conscious states (which of course depend, at least in part, on the
stimuli sensed). For the sake of simplicity,
I’ll just assume that there’s a conscious state for each stimulus “frame,” and
for ≈10 distinct frames/second, there are about 300 million stimulus frames per
year. I’m 43 now, and not sure whether
we should start counting conscious frames from birth or sometime later, but let’s
say that I’m just about to experience my ten billionth conscious state. In my last post, I gave a (very, very) rough
estimate for the minimum number of information bits necessary to specify such a
state. That number may be large – say,
on the order of a trillion bits – but it’s not ridiculous and is less
information capacity than many people have on their mobile phones. Whatever that number happens to be – that is,
the minimum number (B) of bits necessary to specify a particular conscious state
– the point is this: By assumption, the instantiation of those B bits in the
configuration necessary to create conscious state C_{1} will indeed create
that state C_{1}. (For the following
argument, it doesn’t matter whether the mere existence/instantiation of that
particular configuration of bits is adequate, or whether that configuration
must be executed on some general-purpose computer/machine.)

In other words, by assumption, some conscious state C_{1}
is sufficiently encoded by some series of B bits that may look like:
0011010100110111110... (trillions of bits later)... 10001001111100011010. There may be a lot of bits, but the idea is
that if physicalism is true and the information content of any given volume is
finite, then any particular conscious state must be encoded by some string of
bits. If this seems odd to you, it’s
definitely the majority opinion among physicists and computer scientists who actually
think about this kind of stuff. For
example, Scott Aaronson
characterizes the situation this way:

“Look—I don’t know if any of you are like me, and have ever gotten depressed by reflecting that all of your life experiences, all your joys and sorrows and loves and losses, every itch and flick of your finger, could in principle be encoded by a huge but finite string of bits, and therefore by a single positive integer. (Really? No one else gets depressed about that?)”

For the record, I don’t get depressed about that because
I don’t believe it’s true, although I’m still trying to formulate my reasoning
for why. OK, so let’s assume that I have
in fact experienced ten billion conscious states. The state I am currently experiencing is C_{10,000,000,000}
(let’s call it C_{T}), and a tenth of a second ago I experienced conscious
state C_{9,999,999,999} (let’s call it C_{T-1}), and a tenth of
a second before that I experienced C_{9,999,999,998} (let’s call it C_{T-2}),
and so on back. Again, by assumption,
each of these states is encoded by a particular string of bits. So here’s my question: is it possible to just
recreate state C_{T }* de novo*
without, in the process, also producing state C_{T-1}?

Here’s another way of phrasing the question. Is the person who is experiencing conscious
state C_{T} someone who *actually* experienced C_{T-1}
(and C_{T-2} and so on back), or someone who just *thinks/believes*
that he experienced C_{T-1}? Is
there a way to produce someone in state C_{T} without first producing
someone in state C_{T-1}? I don’t
think so; I think that state C_{T} is history dependent and literally
cannot be experienced unless and until preceding state C_{T-1} is
experienced. After all, if conscious
states are indeed history *independent*, then the experience of C_{T}
is precisely the same no matter what precedes it, and that could lead to some
odd situations. Imagine this series of
conscious experiences:

__Series #1__

C_{1000}: sees alligator in the distance

C_{1008}: gets chomped by alligator

C_{1045}: puts tourniquet on chomped arm

C_{2000}: eats own birthday cake

C_{3000}: rides on small plane to experience
skydiving

C_{3090}: jumps out of airplane to experience
thrilling freefall

C_{3114}: pulls rip cord of parachute

C_{3205}: lands safely on ground

If conscious states are history independent, then the
person’s experience at C_{3205} is precisely the same even if the physical
evolution of the world actually caused the following ordering of conscious
states:

__Series #2__

C_{1045}: puts tourniquet on chomped arm

C_{3000}: rides on small plane to experience
skydiving

C_{1008}: gets chomped by alligator

C_{3090}: jumps out of airplane to experience
thrilling freefall

C_{2000}: eats own birthday cake

C_{3114}: pulls rip cord of parachute

C_{1000}: sees alligator in the distance

C_{3205}: lands safely on ground

I can’t see how the above series would make any sense,
but more importantly I can’t see how, even if it did make sense, the experience
of conscious state C_{3205} could possibly be the same in both
cases. If I’m right, it’s because conscious
states are history dependent and state C_{3205} actually cannot be experienced
immediately after C_{1000}.

I’m not sure where I’m going with this. If conscious states are history dependent
(which is what I’ve suspected all along, as in this paper)
then lots of interesting implications follow, such as that conscious states
cannot be copied, consciousness is not algorithmic, etc. (I believe I've already independently shown these implications in this paper.) The above analysis certainly suggests history
dependence but is not a proof. Maybe the
way to prove it is by first assuming that conscious states are independent of
history – in which case conscious state C_{3205}, for example, can be
created *de novo* without first creating conscious state C_{3204}
(which can be created *de novo* with first creating conscious state
C_{3203}, etc.) – and then see whether that assumption conflicts with observations and facts
about the world.

Remember that, by assumption, state C_{3205} is
just instantiated by a (very long but finite) string of bits, say 0011010100110111110... So imagine if we start with a long series of
on-off switches all initially switched off.
We turn some of them on until eventually we have instantiated the
correct series (0011010100110111110...), which encodes state C_{3205}. But it does not (and cannot) matter the order
in which we flip those switches. I have
to think more about the mathematics, but I suspect that in guaranteeing that C_{3205}
is independent of history, so that it and every preceding conscious state can
be instantiated independently of its own history, we will end up needing far,
far more bits than my original estimate of N^T.
I suspect that even the most conservative estimate will show that if conscious
states are history independent, then consciousness will require far more information
storage than is currently believed to reside in the brain.

Then again, I really don’t know. This is still just the initial seed of a thought.