Experience, awareness and consciousness:
suggestions for definitions as
offered by an evolutionary approach.
Foundations of Science 5 (4):429-456. 2000
Mario Vaneechoutte
Department of Clinical Chemistry, Microbiology
& Immunology
Blok A,
Phone: +32/9/ 240 36 92; Fax: +32/9/ 240 36 59
Abstract
It is
argued that the hard problem of consciousness, i.e. the fact that we have
experience, stems from a conceptual confusion between consciousness and
experience. It is concluded that experience has to be considered as a basic
characteristic of ongoing interactions at even the most simple level, while
consciousness is better defined as reflexive awareness, possible since symbolic
language was developed.
A dynamic
evolutionary point of view is proposed to make more appropriate distinctions
between experience, awareness and consciousness. Experience can be defined as a
characteristic linked closely to specific pattern matching, a characteristic
which is already apparent at the molecular level at least. Awareness then can
be regarded as the special experience of one or more central, final modules in
the animal neuronal brain. From evolutionary considerations, awareness can be
understood functionally and physiologically. As such, awareness is what experience
is to animals.
Finally,
consciousness could be defined as reflexive awareness, instead of using the
term as synonymous to awareness. The ability for reflexive awareness is
distinctly different from animal and human awareness and depends upon the
availability of a separate frame of reference, as provided by symbolic
language. As such, words have made reflexive awareness - a specific and
infrequent form of awareness - possible. Conciousness might be defined as the
experience evoked by considering, i.e. thinking about experiences themselves.
Explaining
and understanding awareness and consciousness as evolved biological
characteristics of the functioning of animals and later humans, poses no
philosophical problems. The nature of experience itself remains elusive, but
this is not a problem specific to awareness or consciousness. If there is a
hard problem of explaining consciousness, than this actually must be considered
as the hard problem of explaining experience. While the definition of
experience could be broadened to include all molecular and biological pattern
specific recognition events, the true nature of consciousness might be better
understood when considering it as a very specific form of awareness, made
possible by language.
Keywords
Experience,
pattern matching, dualism, evolution, language, awareness, reflexive awareness,
consciousness.
1. Introduction
1.
Insightful understanding often depends on definitions,
as is expressed in the following quote:
"The
increase of conceptual clarity of a theory through careful clarifications and
specifications is, as William Whewell observed more than a century ago, one of
the most important ways in which science progresses. He called this process
"the explication of conceptions" and showed how a number of theories,
in the course of their temporal careers, had become increasingly precise -
largely as a result of the critics of such theories emphasizing their
conceptual unclarities. Many important scientific revolutions ... have depended
largely on the recognition, and subsequent reduction, of the terminological
ambiguity of theories." (Laudan, 1977).
Indeed, it
is usually overlooked how our definitions and how the terminology we use direct
our thinking, and often guide us into narrow dead end alleys obstructing what
are often straightforward insights.
2.
Recently, many of the discussions about consciousness have centered around the
hard problem of consciousness or have dealt with the question whether there is
something hard at all about consciousness to be explained. To me, as a
biologist with interests in general information and evolution theory, it
appears that most of these discussions actually are about the problem of
explaining what experience might be. So, the usage of the terms
"experience, awareness and consciousness" as synonyms, obstructs
constructive discussion and leads to a confusion of what may be different
concepts.
3. I will
try to show that explaining experience is a more general problem, not directly
linked to understanding what awareness and consciousness are about. Experience
itself might be treated and better understood as a general concept already
apparent at the molecular level, while one might consider awareness and
consciousness then just those kinds of experiences which become possible
respectively with the development of brains in animals and of symbolic language
in humans. The fact that both awareness and consciousness themselves are also
experiences, leads to confusion about their being hard problems to be
explained, while the eventual hard problem is already intrinsic to the
'phenomenon' of experience itself.
4. One
then might accept that there is something irreducible about experience since it
is an intrinsic characteristic of material interaction, of our universe, while on
the other hand one can easily agree with the claim that consciousness is
explained (or explainable). While this manuscript was in preparation, Griffin
(1997) proposed the notion of 'panexperiental physicalism' as a third way -
that is nondualistic interactionism, besides dualism and materialism - to
understand what experience is about. The approach outlined here has been
reached by following a different line of reasoning but is not incompatible with
his hypothesis.
2.
Experience
2.1.
Introduction
5. In an
effort to get a grasp on the concept of experience, I will adopt an
informational, interactive, dynamic point of view on what chemistry and
autonomously duplicating chemistry (life) are. The reader is warned that the
definitions and the approach below may require some shifts in current thinking.
Some patience is asked for. Again, this will be in the first place a matter of
redefining terms, especially by broadening concepts like experience,
interpretation, motivation, etc.
6. The use
of concepts like experience and motivation (and many more) to describe
processes going on at the simplest (organic) chemistry level may seem
anthropomorphic. Still, I would like to remind that considering the use of
these concepts for describing processes of limited complexity as being an
anthropomorphically biased approach can itself be regarded as anthropocentric
reasoning.
2.2.
Experience at the molecular level: chemistry
7. Our use
of the word 'matter' usually invokes the idea of inert pieces of substance,
floating around in space. In our minds, matter is different from interaction
and action because we have separate words for what is actually a continuum: no
material interaction without matter, no interesting material characteristics
when trying to understand matter without interaction. Dualistic reasoning is an
implicit consequence of our basic terminology.
8. Indeed,
only matter as in rocks or gold atoms is rather inert. These kinds of material
configuration are consequently of little interest to understand chemical reactions,
living processes, experience and consciousness. However, other species of atoms
are naturally engaged in interatomic interactions leading to continuous
molecular reconfiguration. Since this interaction occurs according to strict
rules, certain atoms interact with only certain other atoms. As a matter of
fact, one can speak of interpretation: atoms interact with only certain atoms
out of the wide range of atoms present in the immediate environment. This means
that atoms have the capacity to recognize specific patterns. It could be stated
that this specific pattern recognition has to do with experience and that
experience as such can be considered as a basic characteristic of material
interaction.
9. One can
ask why a molecule interacts with other - and only with certain other -
molecules. Again, one is tempted to apply terminology we usually apply only to
describe behaviour of animals and humans by asking: "What is the
'motivation' of molecules to behave in some specific manner?". I will tackle
these questions by considering enzymes, those special interactive molecules
which are a hallmark of living chemistry (just as much as nucleotide strands
are).
2.3.
Experience at the enzymatic level
2.3.1.
Enzymes are repetitive processors
10. The
process of inorganic chemistry is generally a once-only event. Matter (two
atoms or molecules) is reconfigured and strong external forces (energy) will be
necessary to let the process occur again. One could say that the initial
molecules (the substrates) were also the processors, but due to their own
processing activity these processors no longer exist. In the case of an
enzymatic molecule we have a device which can repeat the same process several
times (by the addition of a little external energy) without being changed
physically. The processor still exists after the processing, and flips back so
that the process can be repeated. The activity of the processor does not lead
to its own destruction as is the case for inorganic chemistry. We have a true
processor, repetitively switching on and off, quite well comparable to a
transistor, a human made digital processor.
2.3.2.
Experience as the matching of patterns
11. When
the appropriate substrate is present in the immediate environment of an enzyme,
it is recognized by the active site of the enzyme and this leads to action,
which is the processing of the substrate into product and the subsequent
release of the product. This also makes the enzyme return to its receptive
state. Enzymatic substrate recognition is specific pattern recognition and - as
I proposed to be the case for all other molecular interactions - one could
define experience as 'having to do with specific pattern recognition'. Or one
could say that experience has to do with 'the event of the matching of patterns'.
This resembles strongly perceptive experience as we know it (see paragraphs
36-41). Thus, when the preformed recognition site of the enzyme meets its
fitting pattern, there is experience. Experience is then described as a
characteristic of the interaction between processor and substrate. Experience
can be described in the same terms for e.g. cellular experience (paragraphs
19-24) and experience of multicellular organisms (paragraphs 36-41).
12. Remark
that this definition of experience as already a basic characteristic of
molecular interaction is in accordance with the following suggestion of
Chalmers (1995):
"...,
then experience must be more widespread than we might have believed, as
information is everywhere. This is counterintuitive at first, but on reflection
I think the position gains a certain plausibility and elegance. Where there is
simple information processing, there is simple experience, and where there is
complex information processing, there is complex experience. A mouse has a
simpler information processing structure than a human and has correspondingly
simpler experience" (p. 217).
2.3.3.
Enzymes are interpreters
13. Again,
we might define another concept at this level which is usually assumed to exist
only in complex organisms: interpretation. An enzyme must be able to tell at
least the difference between all possibly present molecules and the one very
specific substrate upon which it will act. Since enzymes pick out only one of
many possible molecules, they interpret the environment.
2.3.4.
Enzymes are motivated and can be in different moods
14.
Besides interaction, perceptive experience and interpretation, one can try to
define motivation and mood at this level of processing complexity, whereby mood
could be defined as the degree of specific motivation, the degree of motivation
to undertake some specific action. Being in a receptive state and having
substrate in its immediate environment, an enzyme is 'forced' to be active, it
has no choice. This is motivation at its most crude appearance. Remark that
perception of the appropriate substrate (perceptive experience) is not
sufficient to let the enzyme undertake its typical catalytic behaviour. The
enzyme must also be in a given state, i.e. in the right mood. Given molecules
of this type (enzyme and substrate), the motivation for the process follows
only from the combination of the experience of inside drives (molecular
tensions inside the molecule) and the experience of the presence of the right
substrate (perception).
15. The
internal drive or mood may differ. Enzymes can find themselves in an activated
status (through phosphorylation by protein kinases) or in an inactivated status
(through dephosphorylation by phosphatases). Also, an enzyme may be in need of
a specific co-enzyme which may alter its conformation in such a way that it can
exert its activity. One could say that these events induce internal experiences
(in the form of altered molecular tensions) which will alter the mood of the
enzyme and which will motivate or demotivate it to undertake action. Similarly,
cells and multicellular organisms will be motivated by the combination of
internally constructed pattern recognition demands and externally present,
specifically fitting patterns. The perception of food will induce animals to
eat only when they are internally motivated by a hungry mood - in other words,
enzymes and animals have to be in the right mood to express certain behaviours.
2.3.5.
A possible explanation for the apparent transience of experience
16. What enzymes
must experience is some specific environmental change, think of changing
electromagnetic fields due to the approach of an external molecule. Chemical
and biological experience might be intrinsically transient because it is a
characteristic for describing the dynamically, transient, temporary interaction
between a specific processor and a specific environmental change (e.g. the
presence of the right substrate). So there is only experience when specific -
pattern matching - conditions are met. It should be emphasized that the pattern
matching itself is not the experience. All one can say about experience is that
'it has to do with' pattern recognition/matching. We will try to show below how
this appears to be also the case for aware experience (e.g. paragraphs 36-41).
17. This
'definition' of experience implicitly holds that experience is transient and
thus might offer a solution to the problem Chalmers had with his own suggestion
(paragraph 12):
"...,
then experience must be more widespread than we might have believed, as
information is everywhere. This is counterintuitive at first, ... Indeed, if
experience is truly a fundamental property, it would be surprising for it to
arise only every now and then; most fundamental properties are more evenly spread."
(Chalmers 1995, p. 217)
2.3.6.
Conclusion
18. I have
tried to show how several concepts which we take to be concealed to the realm
of animal life could be defined already at the molecular level (anorganic and
enzymatic). Certainly enzymes could be regarded as devices which interprete the
environment by picking out only certain molecules and which can be in different
moods, i.e. they can have different degrees of motivation to act, driven by
internal experience of intramolecular tensions. For instance, when enzymes are
not linked to certain co-enzymes or have not been activated, they will not
experience certain molecules as their possible substrates, while these same
molecules will be processed when the enzyme is in the proper mood. The kind of
environmental experience they can have and their behaviour will depend on
internal configurations, i.e. intramolecular tensions which we can consider as
motivations. As such, asking: "How is it like to be an enzyme?" is
more than paraphrasing Thomas Nagels' similar question about bats (Nagel,
1986).
2.4.
Cellular experience
19. We can
now look at the multi-enzymatic processor, the cell. It should be noted that
the product(s) of one enzyme can be used as the substrate for other enzymes.
Enzymes interact by means of chemical molecules, whereby the product of one
enzyme serves as the substrate for another enzyme. In this manner, enzymes
influence each others' behaviour, just like cells and animals do. Such a
community of enzymes, interacting with each other and with the nucleotides
(which are basically carriers of encoded information), embraced by a membrane,
is - roughly speaking - a cell.
20. Cells,
just like enzymes, can respond to specific external molecules which connect to
receptors at the cell membrane. This is pattern matching between intercellular
messenger molecules and cell membrane receptors and we could consider this as
cellular perceptive experience. This will influence the internal behaviour of
the cell, by inducing several enzymatic cascades which would not be happening
without the cellular perceptive experience. The situation is comparable to
enzymatic behaviour which is influenced by the matching of its active site with
the appropriate substrate, or with animals which will behave differently as
influenced by different perceptions.
21. Just
like enzymes, the reaction of cells depends also on their internal motivation.
Cells have to be in the right mood to respond. Neurons for instance will not
always fire when the same amount of dendrite neurotransmitter input is given.
Much depends on which molecules are connected to their membranes. For example,
serotonin receptors are present on the membrane (not in the synapses) and
serotonin can enhance the responsiveness of the neuron. Endorphins and
enkephalins bind to opiate receptors on the membrane and inhibit neurons that
transmit pain impulses.
22. Remark
that cells can also differ in their response to external stimuli depending on
their developmental stage. Maturating cells will respond to other molecules than
mature cells and/or activated cells, because the receptors expressed on their
respective cell membranes differ. This recalls somewhat the different behaviour
of activated/nonactivated enzymes (paragraph 15). Comparably, multicellular
colonies like animals react differently to identical stimuli, depending on the
developmental stage they are in (paragraph 39).
23. Since
the messenger molecules mostly come from other cells and since the products
resulting from cellular activity mostly will be recognized by other cells (to
these other cells these molecules are the observable, external behaviour of the
first cells), cells can interact - again reminiscent of enzymatic interaction -
and may form complex ecological societies, composed of several genetically related
and unrelated cells. A special form of such a community is the multicellular
organism, which is composed of genetically identical cells. It is a temporarily
existing colony of clones produced by duplication of a single germ cell.
24. In
conclusion, it is possible to describe cellular experience in the same terms we
used for enzymes, only there is more flexibility in the interactions and the
whole system is somewhat more complex and flexible. Cellular experience and
behavior can be regarded as simply an extension of the experiential and
behavioral possibilities which exist already at the molecular level, and below
I argue how animal experience, i.e. awareness, is basically only a more complex
experience than that possible at the cellular level.
3.
Awareness
3.1.
Introduction
25. In
what follows I will strictly avoid the use of the term 'consciousness'.
Awareness and consciousness are largely used as synonyms, but I will argue how
awareness and consciousness might be better understood by considering the latter
as a special form of awareness.
26. Native
English speakers reading previous drafts of this manuscript have pointed to the
odd proposition that I, as a nonnative speaker, make above. Of course, one
should regard this proposition within the context of the philosophical debate
on how we can understand consciousness and it is not my intention to change
linguistic habits - something which would be impossible anyway. However,
English, by the presence of two etymologically unrelated terms, nicely offers
the possibility to assign also different meanings to these words.
Interestingly, it appears that English previously made the distinctions I am
advocating here as being more appropriate to structure the debate on
consciousness. Indeed, 'aware' stems from the Anglo-Saxon 'gewaer' (11th
century) which meant something like 'being informed', 'to know' from the 13th
century onwards. I'd say the original meaning of awareness relates to the
having of experiences, the experiencing itself. The etymologic origin of 'consciousness'
points to a more restricted meaning. It is composed of the Latin words 'cum and
sciere' and could be translated as 'to know ABOUT', which points to some
reflexive properties of consciousness, that is to the considering of
experiences. I will come back to this discussion after considerations about the
nature of awareness (paragraphs 56-58).
3.2.
Awareness is what experience is to animals
27. It is
generally agreed that plants are unaware organisms. Usually this difference is
explained by the fact that animals have neurons, and although neuronal
circuitry is indeed essential to animal awareness, this does not explain why
neuronal circuitry should lead to something like awareness. To understand what
awareness is about we have to take into account the special kind of situation
animals find themselves in.
28.
Animals can be defined as multicellular, heterotrophic, eukaryote colonies.
Being a heterotroph colony makes life rather complicated. The basic reason for
the complications is that, as a heterotroph, it is evolutionarily advantageous
when the colony is able to move towards the usually patchily distributed food
like plants or pray. Of course, multiple sessile or almost immobile animal
species and life stages occur, as is the case for parasites or as is the case
in aquatic environments where food is mobile and can be filtered out of the
water. This kind of animal life is usually less complex (e.g. Porifera and
Coelenterata in water and the parasitic Cestoda tapeworms), which is an
additional indication that the mobile animals need to resolve more problems.
Sexually reproducing animal colonies have to be able to move towards potential
sex partners, since these also will be moving around. Also, there are predatory
heterotroph multicellular colonies dwelling around, not feeding on plants but
on other animals and thus animals should be able to flee. In summary, animals
have to be able to move: towards e.g. food and potential sex partners and away
from e.g. danger and annoying conditions. As it turns out, the need for
multicellular heterotroph colonies to be mobile is the basic reason why
muscles, nerves, perception organs, emotions, brains have turned out to be
advantageous characteristics during animal phylogeny. A first indication is
that all of these characteristics are lacking in plants and all or most in
primary or secondary immobile animals.
29. It may
be useful at this stage to summarize briefly some of the characteristics which
differentiate animals from most other living beings. For animals, perceptive
experience - the specific recognition of environmental patterns (be it food,
partners, predators or behaviours of other animals) - is of the utmost
importance to optimize moving. Besides potent perception capacities, animals -
being multicellular colonies - will need special internal motivations to behave
as an individual organism. This could be considered as perception of the
internal metabolic state of the colony. These motivations to make the colony do
the genetically right things are basically hormonal or humoral in nature, i.e.
emotional drives. Humours in turn are nothing but the intercellular signalling
molecules we addressed earlier. Once the colony has perceived (e.g. food), and
is in the right mood (for instance, being hungry) to be motivated by this
perception, it will take action.
30. Most
important with respect to understanding the development of awareness is the
development of neurons, which are simply cells specialized in enhancing the
speed of chemically intercellular signalling transforming the chemical signal
received at the dendrites into an electrical one so that intracellular
transmission proceeds extremely fast, whereafter transformation into a chemical
signal occurs again at the axon. Neurons - with their extraordinary number of
branches and interconnections - enable the development of a nervous system and
of central processing of the experiences going on in the body. It is the
central processing which takes place in the brain which is crucial in
understanding what awareness is about. Other multicellular beings have no
central processing of experiences.
3.3
Awareness is the experience which is the result of filtering and processing the
multiple possible bodily experiences
31. From
neuroscientific and psycho-analytic studies it becomes clear that we are
'unconscious' about many events in our brains and bodies and this is generally
called 'subconsciousness' (paragraphs 44-47). First I want to argue that what
we call awareness is an end stage experience which results from the filtering and
processing of the several possible experiences going on in our bodies and
brains.
32. Many
examples of unaware experiences can be given. Muscular proprioreception is
going on all of the time. It is about monitoring the elongation of muscles in
order to enable continuous muscular correction of bodily equilibrium. None of
this experience (by the monitoring processors) or action (by muscular
contraction and relaxation) usually reaches awareness. We are completely
unaware of it. Also for perception, i.e. the capturing of information from the
outer world by smell, taste, touch, sound and vision, only a limited number of
the experiences of the perception cells and organs reaches the central
experience (final awareness) modules. This becomes clear when we realize that
'we' only experience a limited amount of all the visual information present at
each moment when our eyes are opened. When reading these lines, your brain has
already filtered out many visual signals coming from the surroundings of the
printed letters you look at. It is such a routine that this information cannot
reach awareness (unless written words like those above tell us to attend to
it). For instance, Crick & Koch (1995) suggest that most of the experience
of visual signals in the V1 region of the visual field of our brain never
reaches higher order processing units. See also Bridgeman (1992).
33. There
may be several, mutually not exclusive reasons why we awarely experience, i.e. become
aware of, only a limited amount of all the experiencing of our body and brain.
First, too much information could cause chaos and costs energy and might ruin
living processes by making them chaotic (Kauffman 1995). Enzymes can have only
one kind of experience. They can recognize only one (combined) pattern. Cells
can respond to several hundreds of different molecules docking at their
membranes, and the resulting cellular experiences and activity therefore will
not only be more complicated but also more flexible (more intelligent) than
that of individual enzymes. Still, cells deal with very specific molecules and
are unable to experience the presence of all those other molecules which do not
fit their membrane receptors. Because of this selective blindness, there is a
huge filtering out of all possible information present in the environment. It
can be hypothesized that the increasing problem of filtering out ever larger
amounts of experience may be an evolutionary explanatory reason why filtering
was a necessary development.
34.
Second, only some of the experiences are of relevance to central processors.
Most of the information gathered by local bodily experience is not of
importance to the functioning of the animal for undertaking direct actions as a
whole and therefore need not to be transmitted to higher or the highest level
processing centers. For many processes going on within the colony, there is no
functional reason at all why higher order processors should be informed, even
when the subsystem fails. In the example of visual perception, it is clear that
our retina receives all of the time environmental external information when
awake, but only a very tiny amount of e.g. all of the visual information
reaching our retina is really of importance (paragraphs 36-41).
3.4 How
does the filtering takes place?
35. We may
ask how it is decided, by which level of processing, when and which information
is to be let through to higher order processors and to the final processors
(the awareness modules). A good guess for routine physiological processes is to
say that the higher order processing modules will be activated when the routine
processors at the lower levels cannot handle things on their own and/or when
action (e.g. moving) has to be taken involving the whole colony and not the
subsystem alone.
36. For
perception of the environment we find back in a more elaborated form the
situation as explained for enzymes and cells whereby there is specific pattern
matching between the active site of the enzyme (a preformed pattern recognition
site) and the substrate, or between the membrane receptors of the cell and the
fitting messenger molecules. Similarly, only certain patterns will attract our
attention and will be experienced. They elicit perceptual awareness. Which
patterns are of importance and should be reported to higher order processors,
which patterns fit our matching demands, depends on several cues, which are
determined by different mechanisms.
37. First,
the patterns of importance may have been carved into our brains
phylogenetically: When we observe a curled branch on the ground while walking
in the wood, we all of a sudden may become aware of danger. It has been
suggested that this experience is explainable as an ancient fear of snakes.
Similarly, biologically important patterns like potential partners, food, ...
will attract our attention.
38. Which
patterns are of importance can also be acquired by 'education' during life.
Young animals can learn from the reactions of their parents and kin, which may
be important to recognize dangerous situations or to acquire social skills for
instance by means of punishment and reward. Drug dogs are trained/educated to
observe specific smells, while their untrained counterparts are more versatile
in their smelling preferences. For humans, the pattern of importance can also
be instructed by words or it can be a word itself which attracts attention
because of special reminiscences.
39. There
are also developmental cues. Just as cells will respond differently to certain
stimuli, depending on their developmental stage (paragraph 22), so
multicellular organisms respond differently during their lives because of some
hormonal developments which have taken place. Think of the different
developmental phases of worker bees or of the differences between pre- and
postpubertal humans.
40.
Finally, which experiences are of importance will depend on present other
internal experiences (e.g. hungriness) which we can summarize as the mood of
the colony. For example, our interests are different when angry compared to
when feeling great. A cat in a lazy mood may just as well let a mouse pass by
under its nose.
41. In
summary, for animals, it is decided by phylogenetically given moulds (for
instance snake contours or attractiveness of sexual partners), developmental
stage (for instance changing interests while growing up), previous experiences
(for instance habituation and education), other current experiences (for
instance the current state of internal motivation, like being hungry or not) and
the interaction among all of these, which pattern is to be perceived or
recognized, which experience is to become what we call aware experience.
42. It is
probably about this discontinuity of perceptual experience that Chalmers was
thinking and not about the more fundamental discontinuity we assigned to
experience as it can be described at the molecular level. Basically there is
not really a difference: when we accept that experience is about pattern
matching, the discontinuity of experience follows from the fact that pattern
matching occurs only now and then, whatever the complexity of the pattern
matching demands.
43. One
might say that the distance between the first experiences which will lead to
action becomes larger during evolution (molecular, cellular, animal
multicellular colony), with many more possibilities for flexibility in between.
The more complex the system, the more flexible it is in setting out the
patterns of importance - in combining different filters, the more adaptive it
is to the environment. The degree of responsive flexibility could be defined as
intelligence.
3.5.
Subawareness and final awareness
3.5.1.
Subawareness or modular awareness
44. The
model outlined above, whereby much processing and filtering of bodily and brain
experiences results in some final aware experience, fits with the model of the
modular brain (Gazzaniga, 1985; Gazzaniga, 1996; Bridgemann, 1992). Each of our
brain modules has its own input, processing and signalling specificities, in my
words: each has its own experiences and makes its own interpretations and
decisions. As was the case for enzymes and cells, the behaviour of lower order
modules forms the experiences of higher order modules. Thus a lot of
information will be processed without the higher order processors necessarily
being informed about it. Because most of what is going on in our (body and)
brain remains hidden from the final awareness module(s), we would never have
known about it without the knowledge gathered by e.g. psycho-analysis and
neuroscience.
45. For
example, in split brain patients - as studied by e.g. Gazzaniga (1985), the
mute brain hemisphere was able to answer questions by taking action, although
it could not report to the speaking (aware) brain half. Obviously information
had been perceived and processed, and this could activate motor modules to
undertake the appropriate motoric responses. This seems to be full awareness.
However, since no report to the speaking brain hemisphere could be made, the
patient was unaware of this. Thus, awareness of brain modules and hemispheres,
which even leads to appropriate responses, seems to be possible without the
subject's awareness, in other words without final awareness.
46.
Another example is the phenomenon of blindsight. Here lesions exist in certain
fields of the visual cortex. Although it appears that parts of the brain of
these people is aware of certain perceptions of the retina, this does not lead
to awareness: people think they don't get any information from the retina,
although they score about average when asked to locate objects perceived
visually. The same phenomenon has been described for animals, whereby it could
also be shown that these animals as subjects are not aware of what their brain
knows (Cowey & Stoerig, 1995). With blindsight, it appears that there is no
final or subjective awareness possible because one of the basic modules is not
getting the required information, and/or cannot send through its information.
Still the brain experiences, processes and takes decisions 'unconsciously' or
subawarely.
47. One
could describe the experiences of each brain module as its awareness, and maybe
we can name this better subawareness (instead of unawareness or
subconsciousness).
3.5.2.
Final awareness
48. The
idea that an interpreter module exists has been suggested by Gazzaniga (1985).
I'd prefer to call this the final interpreter module(s), since
interpretation could already be said to exist at the enzymatic level at least
and it could be said that each brain module has the ability to interprete
incoming signals, e.g. as whether these are to be transferred to higher order
modules.
49. From
the above examples, it occurs that final awareness becomes possible only when
certain essential lower order inputs are provided to one or more final awareness
modules. This suggests that what is usually labelled as 'consciousness' is the
experience of some final interpreter module(s), i.e. final awareness. When this
final interpreter module(s) lack certain information from the submodules,
subjects cannot become aware of what certain modules in the brain have
experienced and know.
50.
Gazzaniga (1985) assumes that the 'interpreter module' has to do with language.
Since animals are certainly aware organisms - also because subaware activity
has been shown in animals (paragraph 46) - this seems unlikely. Still, this
interpretation of Gazzanigga (1985) may be understandable: in most humans the
experience of the final interpreter - the aware experience - will be
automatically translated into words, such that it appears that it is in the
more recently developed language centers that the final interpretation is done.
51. One
could define awareness as the final experience of the brain resulting from
filtering by a modular brain - by means of several strongly interacting
criteria (which can be phylogenetic or developmental and which depend on
current internal motivations, previous experiences, environmental cues, etc.).
From this definition it follows that for animals awareness is the only
possible form of experience when awake (Note 1). Hence, another possible reason
for the confusion between experience and awareness: experience can be
understood as both a more fundamental concept of nature and as the specific
animal form of it, awareness - which for animals is what experience is about.
4.
Consciousness
4.1.
Introduction
52. In
what follows, I will consider consciousness as a specific form of awareness,
just as we considered awareness as the specific animal form of experience. I will
try to show how this distinction enables us to address the first person - third
person problem more easily, just as we tried to show how the distinction
between experience as a general concept and awareness as a specific form of
experience allows us to consider the hard problem of aware experience as the
hard problem of experience as a general concept. These ideas will be developed
from the same evolutionary approach used above, by arguing how it is basically
because of recently evolved linguistic capacitities that a new form of
experience, conscious experience, became possible.
53. I
should hurry to explain how ascribing consciousness - or rather, as will become
clear, the possibility for conscious experience - to humans only, does not put
humans on a higher ethical platform than animals. It should be clear from what
precedes that animals do feel (i.e. can have different very deep emotional
experiences), think (i.e. can consider different options before taking action)
and know (i.e. can have the experience of certainty). They are aware emotional
beings that can suffer and enjoy. As a matter of fact our ethical
responsability towards their physical and psychological well being is as large
as our responsability towards newborns and young children. For children as well
as animals the experiences are absolute (here and now (Donaldson, 1992)) -
without any possible comfort or support from relativizing considerations as
they are available to grown-up humans. While we have no problems in feeling
compassionate for the discomfort of children, because we realize that their
experiences are absolute, it is rather strange that most of us do not recognize
that for many animals these same considerations should be kept in mind: when
they suffer, suffering is what they are.
4.2.
Symbolic language and human awareness
54. Having
said this, the argument for considering consciousness as a specific, recently
evolved form of aware experience goes as follows. Awareness combined with
language offers several emergent possibilities, of which "human
awareness" and consciousness are some (Note 2). One could state that
symbolic language is the only basic difference that science has left as a
distinction between humans and animals (Note 3). Besides its role in refined
communicaton and increased thinking capacities (leading to human awareness
(paragraph 55), symbolic language offers the ability to store experiences in
our brain in still a different code and at a separate place from those places
where experiences themselves are stored. Important here is that words provide
us with an internal separate frame of reference, which enables us to take
distance of what is going on and which offers the possibility of conscious
experience (paragraphs 56-58).
55. Am I
conscious, while I am writing this article and searching all possible corners
of my mind for the right words and for useful insights by recombining
information I have read, heard, stored before? I would say I am not. I am
trying to solve problems in the present, using all the skills at my disposition
- including my linguistic and educationally acquired skills, just as cats use
all their native and learned skills when solving the problem of how to catch a
mouse. Just like animals, I try to tackle current problems aided (or disturbed)
by stored previous aware experiences and knowledge and by comparing different
outcomes. Except for the usage of words, there is no difference with animal
awareness. Humans simply can consider more possibilities because of better
developed mental representation capacities and because of words. This is in my
opinion human awareness, not consciousness. Both humans and animals are aware
beings in these situations, neither of them is conscious.
4.3.
Consciousness can be defined as reflexive awareness
56. I will
argue that the concept of consciousness is better restricted to some other
phenomenon, which - like human awareness - also needs both the activitity of
the final interpreter module(s), leading to aware experience or awareness, and
language. I suggest to define consciousness as 'reflexive awareness', i.e. some
kind of experience which is possible because symbolic language enables us to
take distance of the current aware experience, and to observe it as if we were
a third person looking at ourselves.
57. The
distinction I want to point to, may become clear when considering the kind of
aware or conscious questions we can ask. I can ask about the past: 'How did I
get there last time?', which is an aware practical question, BUT I also can
ask: 'How did it feel like to be there two years ago?', whereby I consciously
wonder about previous experiences. About the future, I can awarely ask 'Which
road shall I take next time?' in an effort to prevent possible future problems,
BUT I can also consciously ask 'Will I like it there just as much as last
time?', reflecting upon the possible future experiences theirselves. In present
time, one has to be somewhat more careful in discerning awareness from
reflexive awareness. Both the expressions: 'Which is the right road now?' and 'I
like driving here' are about awareness, whereby the latter is simply a
linguistic translation/expression of a current experience. BUT I also can
wonder: 'Isn't it strange that I am driving a car?' or 'Why do I like driving a
car?', which both are reflexive activities and make me conscious of what I am
doing.
58. From
this it follows that we have the possibility of being conscious, but that most
of the time we are not, being aware 'only'. On the contrary, most of our lives
are spent while being aware of what is going on, which enables us to respond
and react appropriately, but we are not conscious, since we do not use our
ability to take distance.
4.4.
The first person - third person problem
59. This
more restricted definition of consciousness - as a language dependent
possibility to consider the experience of being aware - immediately enables us
to address the first person - third person problem in a rather simple manner.
Having experiences, i.e. being aware, I am first person, very similar to what
happens to an enzyme, a cell or a bat. Thinking about these experiences (and
those of others), I am third person, I am conscious. Since this 'thinking
about' is an experience itself, this puts me back in the first person. Of
course, our ability to take distance can go on and this will be an experience
itself each time, so we can easily imagine thinking about "the experience
of thinking about an experience", i.e. thinking about conscious
experience. This could be compared to a camera observing a TV and representing
its recording on the same TV. The result is a TV representing its own when
representing its own when representing ...
60. In
both first person and third person modus we make use of words. In first person
modus verbal reporting is nothing but an extension of the 'being aware'
process, it is a translation in symbols of the experience itself. In third
person modus, words are used differently. Now they function to take distance
from the present experience and to consider it as an outside observer. Defined in
this manner, first person experience is aware experience, third person
experience is conscious experience.
61.
Related to the first person - third person problem is the kind of experience
(aware or conscious) we will be studying when asking questions to subjects.
When we ask: 'Did you see object x?', we ask about retrieval of stored
experience and we are studying awareness. When we ask 'How did this electric
pulse feel?', we address the nature of the experience, we ask for
considerations about the experience itself and are studying consciousness.
4.5.
Cutting at the joints
62. I have
tried to explain how experience might be described as an intrinsic
characteristic of (at least) certain biochemical processes. To speak of the awareness
or consciousness of an enzyme, a cell or a plant however, is something
different (for a discussion of 'plant consciousness', see Nagel (1997)). Doing
so, we end up with awareness and consciousness (complex higher order
experiences as they became possible with ongoing evolution) as being intrinsic
characteristics of the universe - some cosmic force, which leads to dualism.
Recall that we opted for a nondualistic interpretation by assigning simple
experiential events to simple interactive systems (paragraph 7).
63.
Awareness can be restricted to organisms which rely on central neuronal
processing of bodily and environmental experiences, i.e. to animals. I propose
that a similar distinction is possible between animals and humans. Animals can
feel and animals can know, that is they can have the aware experience of
feeling certain about something. But they cannot know that they know, they
cannot know that they feel. To animals 'knowing' is possible (it is an aware
experience), 'knowing of' (conciousness) is not, because an independent frame
of reference is lacking.
64.
Although we propose that a clear cut is possible between consciousness and
awareness, cutting at the joints is not always easy. After all, complexity
increase is mostly a rather gradual development - think of brain development
and intelligence increase during animal phylogeny from snails and worms to
dolphins, magpies, ... and humans. Still, it is now widely accepted that,
besides gradual evolution, 'symbiosis' - the merging of two unrelated lineages
of doing things -, like that between protein and DNA (leading to the
genetically encoded cell), or between the 'urkaryote' and the bacterial
ancestors of the mitochondria (leading to the eukaryote cell) or between animal
emotional awareness and symbolic sounds (leading to human awareness and the
possibility for consciousness) can cause sudden jumps in evolution, and cause
clearcut differences (see also Note 2).
5.
Mystic experience
65.
Besides aware experience, conscious experience, dream experience (see Note 1),
there is also something like mystic experience. Mystic experience has been
described as a purely emotional manner of experiencing and furthermore as an
experience whereby there is no 'locus of concern' within space/time, that is
that there are no 'here and/or now', 'there and/or then', 'somewhere and/or
sometime' experiences, but only 'out of space-time' experience (Donaldson,
1992).
66. I
think that mystic experience actually boils down for the most part to some kind
of animal experience of direct intensive total mental joy, an experience to
which we have had no access for a long time, because of the immediate
interference of mental representation and words when we do have aware
experience. Except for mystic experience, wordless enjoyment seems an
impossibility to us because we will feel the need to express our joy
("Isn't this beautiful?") and/or try to explain why the 'I' enjoys
("I especially like the way this artist does x, because y and z"),
forgetting to 'just' enjoy. This coincides with the point of view of William
James, who: "... a century ago, pointed out that mystical experience is
not so much invoking higher powers or other realms but losing, albeit briefly,
one's own identity." (citation taken from Blackmore (1994)).
67. It is therefore
maybe not coincidental that inadvertent spontaneous mystic experience such as
is occasionally possible to Westerners seems to occur most frequently (which
probably means 'most easily') when people are subject to deeply emotional and
direct experience of nature itself, when nothing really important is bothering
their mind (my interpretation of examples given by Donaldson (1992)). Eastern
cultures have developed numerous techniques - basically aimed at stopping
thinking and stopping thinking in words - to evoke mystic experience more
easily. There is a more original typically human manner to evoke mystic
experience. It is dancing and trancing, which appears to be a standard part of
rituals and social behaviour in most native cultures.
6.
Zombie experience and artificial consciousness
68. Can
computers have experience? When we defined experience as being apparent at
already the level of simple matter (paragraph 8) and enzymes (paragraph 11), we
should state that transistors (on/off devices) can have experience as well. It
appears that besides electromagnetic experience as it occurs in biochemical and
neuronal processes, a new kind of experience, electronic experience, has been
developed by the scientific activity of humanity. Yes, computers have experience.
69. Since
a computer responds to input and gives as the output what appears to be a
centralized final calculation of all submodular calculations, the computer is
aware when we apply the above definition of awareness. Computer awareness evolves
rapidly: pocket calculators have the experiential complexity of a snail
compared to current computers which can talk to us. Similarly, growing
complexity of brains made increase aware experiential flexibility. Especially
now that we start equipping computers with the possibility of coping with
visual and auditory input, the resemblance to awareness of living organisms
increases. According to the definitions given, computers or AI machines do
experience and - since there is central processing - have aware experience when
sufficiently complex.
70. Are
computers conscious? No doubt we can program computers to consider not the
result of the input and the calculation, in other words to consider the
knowledge, the information which results from experience, but also the event of
the input - the experience - itself. This must not be that difficult since
computers use language and thus have the ability for reflexiveness. When they
are able to consider the experiences themselves or the fact that they have experiences,
computers are conscious according to the above definitions. Will computers one
day be aware and conscious? According to the definitions I suggest here, they
are already or will be no doubt.
71. Is
claiming that machines have or can have experience, awareness and consciousness
the same as claiming that there is no difference between computers and living
beings? I think that again the distinction we tried to make between experience
on the one hand and awareness/consciousness on the other hand enables us to
explain where the difference really lies. The discussion is not about whether
processors, organisms or systems can become aware or conscious, but whether the
underlying experience is comparable. Although computers can be aware and
conscious, this experience will compare in no way to the aware and conscious
experience which is possible in animals and humans respectively.
72. The
most probable reason for this difference is that the basic experiences in
bodies and brains (hormonal and interneuronal signalling) are of a different
nature than the basic experiences of computers (signalling between
transistors). Maybe the most important reason is something which has been clear
to many students of living organisms for a long time, but which has always been
overlooked, avoided or denied by science: animals and humans are emotional
organisms in the first place (Vaneechoutte, 1993). This trivial insight is
fortunately and finally finding more and more acceptance. According to the
hypothesis of Antonio Damasio (1994), emotion pervades and underlies aware
reactions even more deeply than was believed by those of us who were already
convinced of its importance.
73. So, we
might also get a grip on the zombie discussion by stating that zombies and
computers can indeed be defined as aware and possibly conscious 'beings', but
that their awareness and consciousness is of a different kind from ours,
because they deal with a different kind of experiencing, that is insentient or
nonemotional experiencing. Only in the case that we could program emotionality
into computer brains might it be possible that one day computers might have
aware and conscious experiences comparable to ours. Theoretical work on how
'appraisive knowledge' could be programmed into computers so as to lead to
'emotional' behaviour has already been formulated (Gudwin & Gomide 1997).
Others say that the objectives of an AI system could be put to 'please human
beings' or to 'pay attention to approval and disapproval of human beings'
(Walter Fritz, personal communication).
7.
Experience and experiences
74. We end
up with many classes of experience: molecular biochemical experience, cellular
experience, subaware brain module experience, final aware experience, language
dependent conscious experience, dream experience, mystic experience and AI or
zombie experience.
75. Just
as mystic experience might be understood as pure direct emotional animal
experience, so we can understand zombie experience as the experience which is
possible for emotionless, insentient machines. They are just different
experiences, by definition. We cannot know what the world of AI experience is
like, just like most of us cannot imagine what mystic experience is about. The
experiences of a bat, for which the world is composed of sonar images in air,
will be different from the experiences of a dolphin, for which the world is
'seen' as sonar images in water, or from those of land animals which use vision
and sound in air, etc. And all of these will be impossible to imagine to a
human mind. We may come closest to understanding how it must be to be some
other human being, simply because we are most alike. Still, all of this can be
considered as aware experience, while no one can really understand how it must
be like to be another being. This coincides with the vision of the mind as the
product of the interaction of brain, body and environment, whereby there is not
really a mind-body duality. As such, the world view of a mind is a specific
reflection of the very specific combination of physical and environmental
present and past experiences of an individual colony or system.
8.
Summary
76. In
summary, experience can be considered as a basic characteristic of material
interaction starting (at least) at the level of enzymatic processes.
Understanding what experience is about is a hard problem. All I can offer as a
way to an answer is that it has to do with pattern recognition or
pattern matching, which explains the transiency of experience. The essence of
animal awareness is that it is the final experience possible when experiences
are first processed in a central brain, and as such awareness is the most
frequent experience possible at the animal level. On this view, in nature only
animals can be regarded as possibly aware beings.
77. Human
awareness is an extension of animal awareness by the possibility of storing
information in an independent manner, by means of words (linked to mental
representations). It makes us much better able to retrieve events in the past,
it offers the new possibility to consider events in the future and it enables
us to consider many more possible outcomes of present events. It also enables
us to translate present experiences into words. Words also may be used to
construct imaginary (virtual) situations in which we can have vivid (as if)
aware experiences.
78. This
is not to be confused with the use of words for imagining how experiences were,
are or could be and which I suggest to define as having to do with
consciousness. Consciousness then is the ability, again offered by language, to
consider the experiences themselves: how were events experienced in the past,
what will events feel like in the future, how do others experience things. In
the present tense we can wonder about the experiences we are having or wonder
about the fact that we have experiences - which again should not be confused
with the aware activity of reporting present experience. For example, saying 'I
like this' is aware activity, while saying 'Quite surprising that I like this'
is conscious activity.
79. While
awareness is (animal) experience, conciousness can be defined as the
experience which stems from considering experiences, or as reflexive awareness
(third person activity). Conscious activity itself is awarely experienced,
which puts us back in first person modus. Besides these pitfalls, I think the
basic confusion in many discussions on consciousness stems from taking these
specific animal and human experiences to be the only kind of experience
possible, overlooking that experience is an intrinsic feature of the
interaction between matter.
80. I have
tried to argue how evolutionary, dynamic reductionism may enable us to some
degree to distinguish between experience, awareness and consciousness. I
conclude for myself that there are no philosophical problems about awareness
and consciousness. Mechanistically, aware and conscious activity can indeed be
considered as explained (Dennett 1991). However, I think that explaining how
these experiences feel like and why it should feel like something, is not
within the realm of our methods of understanding. To me this comes as no
surprise, since I consider our lack of understanding of the nature of
experience as a consequence of the evolutionary limitations of our individual
animal minds, developed to think in terms of cause and consequence. We should
adopt some modesty in these matters. After all, also our basic laws are merely
descriptive: they enable prediction, but they do not explain why things are the
way they are. The physical laws which science has revealed, give us a false
impression of basic understanding, while these laws only reflect some
generalities, without explaining why these generalities are the way they are.
We can describe under what conditions two molecules will interact and predict
to which new molecule this will lead. We describe how it happens, but we do not
understand why this happens.
81. I hope
that this approach may provide a manner for making elementary distinctions
between experience, awareness and conciousness and that it may offer a way to a
renewed constructive debate between those researchers and philosophers who find
themselves at present in opposite camps. Possibly the ideas of D.R. Griffin
(1997) offer a way out in the same direction.
9.
Notes
82. Note
1. Of course there is also dreaming experience during sleep. One could say that
dreaming activity occurs during every normal sleep, but that we experience
dreams only sporadically (some even report to have never dream experiences). My
guess is that this dream experience stems from 'partial awakeness', i.e. a
state of being whereby some of the modules which are otherwise inactivated
during sleep regain activity. This might occur because of environmental
conditions (think of noises), because of malfunctioning of some organs during
sleep (think of apnoea) or because of the emotional impact of the dreams
themselves, which alert some modules otherwise 'asleep'. At those moments we
are able to witness the complexity and the seeming chaos of the interpretation
processes of lower order modules in the absence of our final interpretation
capacities. (To humans there is also conscious experience and
mystic/religious/hallucination experience. For a preliminary attempt at
classification, see paragraphs 54-61, 85 and 65-67).
83. Note
2. As a matter of fact, there is nothing nondeterministic about the enigmatic
word 'emergence' (Nagel 1961) - also 'supervenience'. Instead of stating that
the sum is more than the parts (a quantititave approach, which is not
applicable), we might better understand emergence by saying that the qualities
of the combination are different from the qualities of its constituent parts (a
qualitative approach).
84.
Combining two different processes, like i) being an emotional animal and ii)
speaking - can lead to predictable emergent outcomes. i) An animal has emotions
which have been naturally selected because they enable appropriate behaviour
needed to survive and reproduce (paragraph 29). ii) A certain animal species
(the human animal) is able to speak and thus to think about future possible
events (like death) and future possible emotional experiences (like how it will
feel to be dead). An almost inevitable outcome of i) and ii) together is that
these animals will develop behaviour which is meant to influence the assumed
afterdeath events and emotional experiences. As such, one could say that the
worldwide occurrence of independently developed burial rituals is a predictable
emergent outcome of the combining of emotion and speech in a single organism.
85. The
recurrent need throughout our history and at present of most humans to believe
in the existence of divine powers (religiosity) can be explained starting from
the same considerations (Vaneechoutte 1993) and as such religiosity becomes a
subject for scientific studies, pace those who claim that science has nothing
to say about religion. While science cannot proof or disproof the nonexistence
of deity, it can wonder what it is in the human mind that makes so many of
these minds convinced of something for which absolutely no trace can be found
when applying the otherwise very efficient scientific methods.
86. Note
3. However, even the exclusivity of symbolic language for humans may be
questionable, since we still have very little idea of the degree of
symbolisation of the sonar languages of e.g. dolphins and bats or of the
infrasound language of elephants.
Acknowledgements
I
sincerely thank Margaret Donaldson for her open minded and very constructive
criticism and for pointing to some essential shortcomings in the original
draft(s) of this paper.
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