HOW TO DEFINE CONSCIOUSNESS—AND HOW NOT TO DEFINE
Max Velmans, Goldsmiths, University of London, New Cross, London SE14 6NW; email
Journal of Consciousness Studies, 16(5), 2009, pp 139-156
Definitions of consciousness need to be sufficiently broad to include all examples of
conscious states and sufficiently narrow to exclude entities, events and processes that are
not conscious. Unfortunately, deviations from these simple principles are common in
modern consciousness studies, with consequent confusion and internal division in the field.
The present paper gives example of ways in which definitions of consciousness can be either
too broad or too narrow. It also discusses some of the main ways in which pre-existing
theoretical commitments (about the nature of consciousness, mind and world) have intruded
into definitions. Similar problems can arise in the way a “conscious process” is defined,
potentially obscuring the way that conscious phenomenology actually relates to its neural
correlates and antecedent causes in the brain, body and external world. Once a definition of
“consciousness” is firmly grounded in its phenomenology, investigations of its ontology and
its relationships to entities, events and processes that are not conscious can begin, and this
may in time transmute the meaning (or sense) of the term. As our scientific understanding of
these relationships deepen, our understanding of what consciousness is will also deepen. A
similar transmutation of meaning (with growth of knowledge) occurs with basic terms in
physics such as "energy", and "time."
Why is it difficult to define consciousness?
As George Miller wrote in 1962, "Consciousness is a word worn smooth by a million tongues."
Almost 50 years later, little has changed. The term means many different things to many
different people, and no universally agreed "core meaning" exists. This is odd, as we each have
"psychological data" about what it is like to be conscious or to have consciousness to serve as
the basis for an agreed definition.
This uncertainty about how to define consciousness is partly brought about by the way global
theories about consciousness (or even about the nature of the universe) have intruded into
definitions. In classical Indian writings such as the Upanishads, consciousness is thought to be
the essence of Ātman, a primal, immanent self that is ultimately identified with Brāhman—a
pure,transcendental, subject-object-less consciousness that underlies and provides the ground
of being of both Man and Nature (Sen, 2008). In the classical Western tradition, "substance
dualists" such as Plato and Descartes bifurcated the universe, believing it to consist of two
fundamental kinds of stuff, material stuff and the stuff of consciousness (a substance
associated with soul or spirit). Following the success of the brain sciences and related sciences,
20th Century theories of mind in the West became increasingly materialistic, assuming physical
“stuff” to be basic, and consciousness in some way “supervenient” or dependent on the
existence of physical forms. For example, "property dualists" such as Sperry (1969) took
consciousness to be a special kind of property that is itself non-physical, but which emerges
from physical systems such as the brain once they attain a certain level of complexity. Taking
materialism to its logical conclusion, "reductionists" such as Crick (1994) and Dennett (1991)
argued consciousness to be nothing more than a state or function of the brain. Within
cognitive psychology, there were many similar reductive proposals which identified
consciousness with some aspect of human information processing, for example with working
memory, focal attention, a central executive, or a “global workspace”(e.g. Baars, 1988).
It should be apparent that these wide-ranging disparities arise more from pre-existing
theoretical commitments (about the nature of consciousness, mind and world) than from the
everyday phenomenology of consciousness itself. In the modern literature, for example,
Dennett provides a prominent example of the triumph of materialist theory over
phenomenological evidence when he tried to deny the very existence of phenomenal qualities
(as normally understood). He made this perfectly clear when he writes: "Philosophers have adopted various names for the things in the beholder (or properties of the beholder) that have been supposed to provide a safe home for the colours and the rest of the properties that have been banished from the external world by the triumphs of physics:raw feels, phenomenal qualities, intrinsic properties of conscious experiences, the qualitative content of mental states, and, of course, qualia, the term I use.
There are subtle differences in how these terms have been defined, but I am going to ride roughshod over them. I deny that there are any such properties. But I agree wholeheartedly that there seem
to be." (Dennett, 1991, p372 - my italics)
Dennett arrives at this view by presupposing that information about brain and behaviour
obtained from a third-person perspective is scientific and reliable, while first-person data about
conscious experience tells us nothing about its ontology at all.1
European phenomenology and classical Indian philosophy assume the opposite to be true. Accordingly, their investigations of consciousness have been primarily phenomenological.2 Within modern consciousness studies there are also many intermediate theoretical positions with associated research paradigms that take both the existence of the material world and the existence of
I have given a detailed critique of this aspect of Dennett’s position that I do not have space to repeat here (see Velmans, 2001, 2007a, 2009 chapter 5); see also Zahavi (2007), Beenfeldt (2008).
See Gallagher, 2007, Zahavi, 2007 for recent reviews of European phenomenological approaches.
Note however that classical Indian conclusions about the nature of consciousness arise largely from altered conscious states consequent on prolonged periods of meditation, and this can be an additional source of confusion when comparing Eastern and Western understanding of everyday conscious phenomenology. The pure, contentless consciousness said to be experienced in such states is, in various writings, thought to underly all of Nature, which makes this a claim about what in the West is sometimes referred to as “the ground of being” or, in Kantian terms, “the thing in itself,” rather than a claim about the forms of “phenomenal consciousness,” that are more usually investigated in modern consciousness studies. consciousness seriously, for example viewing first- and third-person investigations of the mind/brain as complementary sources of information about its nature.
It should come as no surprise that such diverse assumptions about the nature of consciousness and howwe can study it have created divisions between research communities that can be difficult to cross. There can, for example, be no point of convergence and certainly no consensus between
researchers who take the existence of conscious phenomenology to be both self-evident and
ontologically primary, with those who give no credence to that phenomenology at all.
Given this diversity, some consciousness researchers have doubted that a systematic study
of “consciousness” as such, is even possible. Sloman (1991) for example argued that "people who
discuss consciousness delude themselves in thinking that they know what they are talking about...it's
not just one thing but many things muddled together"—rather like our "multifarious uses of ‘energy’
(intellectual energy, music with energy, high energy explosion, etc.)", and Stanovich (1991) complained that "the term "consciousness" fractionates into half a dozen or more different usages." For him, “consciousness” is a "botched concept"; a psychiatric institution is too good for it—and it deserves the "death penalty." Given this, they suggest that one can make no generalisations about it.
The obvious counterargument is that there is nothing to prevent discussion and organised research into aspects of “consciousness” denoted by a given, specific usage of that term. The multiple uses of the term “energy” in natural language have not in any way impeded a systematic study of energy in physics.
Similarly, the flourishing of consciousness studies over the last 20 years has made it clear that, despite its diverse referents in natural language, a systematic study of “consciousness” is both possible and actual. For research to proceed, all one needs is a sufficiently well-specified use of the term for a
community of researchers to agree that they are investigating the same thing.
To what does the term "consciousness" refer?
But where should we begin? As with any term that refers to something that one can observe
or experience it is useful, if possible, to begin with an ostensive definition, i.e. to "point to" or
"pick out" the phenomena to which the term refers and, by implication, what is excluded.
Normally we point to some thing that we observe or experience. The term “consciousness”
however refers to experience itself. Rather than being exemplified by a particular thing that we
observe or experience, it is exemplified by all the things that we observe or experience.
Something happens when we are conscious that does not happen when we are not
conscious—and something happens when we are conscious of something that does not
happen when we are not conscious of that thing. We know what it is like to be conscious when
we are awake as opposed to not being conscious when in dreamless sleep. We also know what
it is like to be conscious of something (when awake or dreaming) as opposed to not being
conscious of that thing.
This everyday understanding of consciousness based on the presence or absence of
experienced phenomena provides a simple place to start. A person, or other entity, is
conscious if they experience something; conversely, if a person or entity experiences nothing
(See Velmans 1991b, 2007b for introductions to this form of “psychological complementarity”, and readings in Varela & Shear ( 1999), Velmans (2000), Jack & Roepstorff (2003, 2004) they are not conscious. Elaborating slightly, we can say that when consciousness is present, phenomenal content (consciousness of something) is present. Conversely, when phenomenal content is absent, consciousness is absent. This stays very close to everyday usage and it provides a simple place of departure on which widely diverging theories can agree.It also makes sense to stay as close as possible to everyday, natural language usage for related terms. In common usage, the term
"consciousness" is often synonymous with "awareness", "conscious awareness", and
“experience”. For example, It makes no difference in most contexts to claim that I am
"conscious of" what I think, "aware of" what I think, "consciously aware" of what I think, or
that I can “experience” what I think. Consequently, to minimise confusion, it is important not
to load these terms with added meanings that are peculiar to a given theoretical position.6
This applies equally to the “contents of consciousness”. The "contents of consciousness"
encompass all the phenomena that we are conscious of, aware of, or experience. These
include not only experiences that we commonly associate with ourselves, such as thoughts,
feelings, images, dreams, body sensations and so on, but also the experienced three dimensional world (the phenomenal world) beyond the body surface.
Some important distinctions
However some terminological distinctions are important. In some older writings, for example
in the work of Descartes, "consciousness" is not clearly differentiated from "mind." Given the
extensive, current evidence for preconscious and unconscious mental processing, this usage is too broad. How phenomenal consciousness relates to preconscious and unconscious mental
processing is now a major topic for psychological research. To avoid confusion, and to enable
such research, it is important to reserve the term "mind" for psychological states and processes
that may or may not be "conscious".
Descartes also famously believed thought to epitomise the nature of consciousness, and
consequently defined it as a “substance that thinks” (res cogitans), which distinguishes it (in his
view) from material substance that has extension in space (res extensa). Modern psychology
accepts that verbal thoughts (in the form of phonemic imagery or ‘inner speech’) are amongst
It is worth noting that Eastern philosophies refer to a state of "pure consciousness," without any phenomenal contents (Shear & Jevning, 1999, Shear, 2007), although many characterisations are nevertheless offered of this state, such as sat-chit-ananda (being-consciousness-bliss) in Hindu thought, or sunyata (emptiness) in Mahayana Buddhism (Fontana, 2007). As these possibilities do not have a direct bearing on the problems of defining consciousness within the Western discourse, we can safely leave them to one side for now, without dismissing them.
Even eliminative/reductive theories such as Dennett’s agree that that conscious phenomenology seems to exist, and this provides the point of departure for their attempts at phenomenal elimination/ reduction. For example in some theories "awareness" is thought of as a form of low-level consciousness that is distinct from full consciousness. This is not a serious problem for the present proposal, provided that the situation described has some phenomenal content (for example where one is dimly aware of a stimulus). However serious confusions can arise in situations where the term "awareness" is applied to situations where there is no relevant phenomenal content, for example, when "awareness" refers to preconscious information processing, or worse, to the non-conscious information processing which accompanies consciousness (as proposed by Chalmers, 1995). In the present usage, being "aware of" non-conscious information processing is a contradiction in terms. (See, for example, Dixon (1981), Kihlstrom (1987), Velmans (1991b), Reber (1993), Wilson (2002), Goodale & Milner (2004), Jeannerod (2007), Kihlstrom, Dorfman & Park (2007), Merikle (2007)
the contents of consciousness. However it does not accept that thoughts exemplify all conscious contents. Unlike thoughts, pains, tactile sensations, itches and other body experiences appear to have both spatial location and extension in different regions of the body, and the sights and sounds of the experienced external world (the phenomenal world) appear to have locations and extensions in a surrounding three-dimensional space.
These interoceptive and exteroceptive experiences also differ widely from each other and many
descriptive systems have been developed for investigating their phenomenology (in studies of
visual and auditory perception, emotion, pain, and so on). It should be evident that such
developments in phenomenology are an essential first step in characterising what it is about
consciousness that needs to be explained—and that restricting the phenomenology of
“consciousness” to the phenomenology of “thought” is too narrow.
In other, more modern writings, "consciousness" is sometimes taken to be synonymous with
"self-consciousness". As one can be conscious of many things other than oneself (other people,
the external world, etc.), this usage is also too narrow. To allow a clear distinction between
consciousness of oneself and consciousness of things other than oneself, it makes more sense
to reserve the term “self-consciousness” for a special form of reflexive consciousness in which
the object of consciousness is the self or some aspect of the self.
The term "consciousness" is also commonly used to refer to a state of wakefulness. Being
awake or asleep or in some other state such as coma clearly influences what one can be conscious of. However these global states have a complex relationship to phenomenal consciousness. When sleeping, for example, one can still have visual and auditory experiences in the form of dreams. Conversely, when awake there are many things at any given moment that one does not experience. So in a variety of contexts it is necessary to distinguish "consciousness" in the sense of "phenomenal consciousness" from wakefulness and other states of arousal, such as dream sleep, deep sleep, and coma. Finally, "consciousness" is sometimes used to mean "knowledge", in the sense that if one is conscious of something one also has knowledge of it. This is an important feature of consciousness (that I do not have space to examine here).
However, at any moment, much knowledge is unconscious, or implicit (for example, the knowledge gained over a lifetime, stored in long-term memory). So consciousness and knowledge cannot be co-extensive.
It is widely accepted that many experienced phenomena have apparent location. Whether there is also a sense in which such phenomena also have a real spatial location and extension (in the phenomenal body and external world outside the brain) is a fundamental, contested issue within current consciousness studies that goes beyond the scope of the present paper. Detailed evaluations of the competing arguments are given in Velmans (2008, 2009 chapter 7).
It remains useful to distinguish the various global conditions for the existence of consciousness (for example the differences between being awake, in dream sleep, dreamless sleep, and deep coma) from the added conditions which determine its varied phenomenal contents (for example having visual rather than auditory experiences). However, for the purposes of finding an agreed, core definition of phenomenal consciousness from which investigations can proceed, it makes sense to retain the convention that unless one is conscious of something one is not conscious. Conversely if one is conscious of something (e.g. while dreaming) one is conscious.
Phenomenal consciousness enables a special kind of knowledge: To be conscious of something is to know it in a way that makes itsubjectively real. Bertrand Russell called this “knowledge by acquaintance”, which he contrasted with the more abstract “knowledge by description” provided by verbal descriptions. This important, first-person function of phenomenal consciousness and its relation to the many proposed, third-person functions of consciousness is discussed in detail in Velmans (2009 chapters 12, 13, and 14).
The above, broad definitions and distinctions have been quite widely accepted in the
contemporary scientific literature (see, for example, Farthing, 1992; readings in Velmans, 1996,
Velmans & Schneider, 2007)—although by no means universally, as we will see below. Agreeing on definitions is important. Once a given reference for the term "consciousness" is fixed in its phenomenology, the investigation of its nature can begin.
How not to define consciousness
As noted above, reductionists and non-reductionists adopt fundamentally differing
assumptions about the ontology of consciousness and there are many instances where these
differing assumptions about ontology have intruded into how phenomenal consciousness
has been defined. It is common for example for reductive physicalists and functionalists to
take it for granted that an advanced form of brain science will ultimately demonstrate
phenomenal consciousness to be nothing more than a state or function of the brain. If so,
nothing would be lost by defining it in that way. However most theories of consciousness
that resist a reduction of conscious phenomenology to brain states and/or functions fully
accept that there is an intimate relationship between consciousness and brain. What is at
stake is the nature of this intimate relationship. For example, physicalist, functionalist,
naturalistic dualist and modern dual-aspect theories agree that, in humans, every distinct
conscious experience is likely to be accompanied by distinct, correlated conditions in the brain
(the neural correlates of consciousness or NCC), but naturalistic dualist, and dual-aspect
theories resist the reduction of phenomenal consciousness to brain states. Dual-aspect theory
for example suggests that conscious experiences and their correlated brain states are how the
mind appears when viewed from respectively first- and third-person perspectives, and that
these aspects of mind are complementary and mutually irreducible (see e.g. Velmans, 1991b,
2009 chapter 13).
If so, the discovery of the neural correlates of given experiences will not settle the fundamental differences amongst these theories. Nor would the discovery of antecedent neural causes settle these differences. To achieve a genuine reduction, conscious experiences would have to be shown to be ontologically identical to their neural causes and/or correlates. Discovery of the neural causes and or correlates would not achieve this for the simple reason that causation, correlation and ontological identity are fundamentally different relationships.
In short, no ontological view is automatically privileged by the likely advance of science, and,
given the far-reaching consequences of reductionism and its alternatives it is important not to
define phenomenal consciousness in a way that presupposes the outcome of this debate, or
finesses it in favour of one outcome or another. Unfortunately, this practice is widespread
both in common culture13 and in the scientific and philosophical literature. Dennett, Searle,
Chalmers (1996) provides a naturalistic dualist analysis of how conscious experiences relate to brain states that is similarly non-reductionist.
If A is identical to B, then B is identical to A (symmetry) and all the properties of A and B must be identical (Leibniz’s law). If A correlates with B, then B correlates with A (symmetry), but it does not follow that all the properties of A and B must be identical (correlation need not obey Leibniz’s law). If A causes B, it neither follows that B causes A, nor that the properties of A and B are identical (neither symmetry, nor Leibniz’s law)— for a fuller discussion see Velmans (1998, 2002, 2009 chapter 3). For example newspaper reports of PET or fMRI scans producing ‘pictures of conscious thoughts’, emotions etc. in the brain are ubiquitous, completely oblivious of the fact that these are actually indirect measures of activities that correlate with the experiences in question rather than pictures of the experiences themselves,
Block, and Baars provide a few prominent examples (amongst many). As noted above,
Dennett simply declares first-person access to phenomenal qualities to have no place in
third-person science, and, therefore, no ultimate place in an understanding of consciousness at all! Searle (2007), by contrast, fully accepts that conscious states have special phenomenal properties, for example that they are intentional (about something), subjective, and private (viewable only from a first-person perspective)—all characteristics that traditionally distinguish the mental from the physical. However he then simply declares such facts about consciousness to be ‘objective physical facts’ about the brain, thereby reducing the domain of the “mental” to a subclass of what is “physical” by an act of redefinition—but leaving the problem of how objects such as brains could produce such intentional, subjective, private states untouched. Block (1995) also entirely accepts the
existence of phenomenal consciousness (with its special properties). However, he argues
that there is another kind of consciousness, which he terms “access consciousness” that
enables “information access” in the central nervous system, thereby giving consciousness a
major role to play in the brain’s activities. While this avoids reducing phenomenal
consciousness to a function of the brain, this redefinition of information access as “access
consciousness” risks inflating a brain function to a conscious status that it does not possess.
Information access and information availability have been widely recognised aspects of
human information processing since the advent of cognitive psychology in the 1960’s, and it
is true that information which enters phenomenal consciousness can be accessed,
rehearsed, entered into long-term memory, used for the guidance of action and so on.
However, the processes that actually enable information access, rehearsal, transfer to longterm memory and guidance of action are not themselves conscious (if they were there would be no need to subject such processes to detailed investigation within cognitive psychological research—see Velmans, 1991a). In short, “access consciousness” is not actually a form of consciousness. The conscious part of “access consciousness” is just phenomenal consciousness, and the processes that enable access to items in phenomenal consciousness are not conscious at all.
How to define a “conscious process”
For the purposes of definition, the importance of retaining an initial, clear distinction between
information processing and the conscious experiences that may or may not accompany it becomes
evident as soon as one reflects on the very different ways that the term “conscious process” has
been used in the literature. In Velmans (1991a) I have argued that the psychological and
philosophical literature confounds three distinct senses in which a process might be said to be
“conscious.” It might be conscious:
(a) in the sense that one is conscious of the process
(b) in the sense that the operation of the process is accompanied by consciousness (of its
results) and and completely oblivious of the fact that the phenomenology of a subject’s experiences cannot be viewed from a third-person perspective (the classical philosophical problem of “other minds”).
(c) in the sense that consciousness enters into or causally influencesthe process.
We do not have introspective access to how the preconscious cognitive processes that enable
thinking produce individual, conscious thoughts in the form of “inner speech.” However, the
content of such thoughts and the sequence in which they appear does give some insight into
the way the cognitive processes (of which they are manifestations) operate over time in
problem solving, thinking, planning and so on. Consequently such cognitive processes are
partly conscious in sense (a), but only in so far as their detailed operation is made explicit in
conscious thoughts, thereby becoming accessible to introspection.
Many psychological processes are conscious in sense (b), but not in sense (a)—that is, we are
not conscious of how the processes operate, but we are conscious of their results. This applies
to perception in all sense modalities. When consciously reading this sentence for example you
become aware of the printed text on the page, accompanied, perhaps, by inner speech
(phonemic imagery) and a feeling of understanding (or not), but you have no introspective
access to the processes which enable you to read. Nor does one have introspective access to
the details of most other forms of cognitive functioning, for example to the detailed operations
which enable “conscious” learning, remembering, engaging in conversations with others and so
Crucially, having an experience that gives some introspective access to a given process, or
having the results of that process manifest in an experience, says nothing about whether that
experience carries out that process. That is, whether a process is “conscious” in sense (a) or (b)
needs to distinguished from whether it is conscious in sense (c). Indeed, it is not easy to
envisage how the experience that makes a process conscious in sense (a) or (b) could make it
conscious in sense (c). Consciousness of a physical process does not make consciousness
responsible for the operation of that process (watching a kettle does not determine when it
comes to the boil). So, how could consciousness of a mental process carry out the functions of
that process? Alternatively, if conscious experience results from a mental process it arrives too
late to carry out the functions of that process.
How not to define a “conscious process”
It is nevertheless common for theorists to contrast human information processing that is either
accompanied or not accompanied by a conscious experience, and then attribute any functional
differences in processing to the activities of consciousness. Indeed Baars & McGovern (1996)
explicitly advocate this method (which they call “contrastive analysis”) for determining the
functions of consciousness. As they point out, the brain has hundreds of different types of
unconscious specialised processors such as feature detectors for colours, line orientation and
faces, which can act independently or in coalition with one another, thereby bypassing the
limited capacity of consciousness. These processors are extremely efficient, but restricted to
their dedicated tasks. The processors can also receive global messages and transmit them by
‘posting’ messages to a limited-capacity, global workspace whose architecture enables systemwide integration and dissemination of such information. Such communications allow new links
to be formed between the processors, and the formation of novel expert ‘coalitions’ able to
work on new or difficult problems. Once processes enter the global workspace they ‘become
conscious’, and Baars & McGovern assume the functions of the global workspace to be the
functions of consciousness. Within their model, the global workspace is essential for
organising novel, complex activities. Given this, it is not surprising that they find many things
for phenomenal consciousness to do. For example:
- By relating input to its context, consciousness defines input, removing its ambiguities in perception and understanding.
- Consciousness is required for successful problem solving and learning, particularly where novelty is involved.
- Making an event conscious raises its “access priority,” increasing the chances of successful adaptation to that event.
- Conscious goals can recruit subgoals and motor systems to carry out voluntary acts.
- Making choices conscious helps to recruit knowledge resources essential to arriving at an appropriate decision.
- Conscious inner speech and imagery allow us to reflect on and, to an extent, control our conscious and unconscious functioning.
- In facing unpredictable conditions, consciousness is indispensable in allowing flexible responses.
“In sum, consciousness appears to be the major way in which the central nervous system
adapts to novel, challenging and informative events in the world” (Baars & McGovern, 1996,
Global workspace theory provides one of the best, current models of brain functions closely
associated with consciousness. Given this, why should an identification of consciousness with
the operations of the global workspace present a problem? For Baars, a third-person account
of consciousness in terms of information in a global workspace is an account of subjective
experience—that is, it is an account of consciousness as such (Baars, 1994, 2007). But the
difficulties of incorporating first-person, phenomenal consciousness within a third-person
account of information processing in this way are well illustrated by Baars’ many different
attempts to grapple with this issue:
In his earlier writings, Baars (1991) equated consciousness with focal attention, arguing that
they “covary so perfectly, we routinely infer in our everyday life that they reflect a single
underlying reality.” Later, however, Baars (1997a) modified his position to viewing attention as
the “gatekeeper” for the global workspace and therefore the gatekeeper to consciousness.
Thus, “attention creates access to consciousness”, but “consciousness is needed to create
access to unconscious processing resources”, and “... we can create access to any part of the
brain using consciousness.” (Baars, 1997b, p296; see also Baars et al, 1997) In short,
consciousness is now thought to carry out the many functions which require global access to
unconscious processing resources such as system-wide integration and dissemination of
information, the formation of new links between unconscious processors, and so on (and this
remains his position, as noted above). Unfortunately, in his summary of his 1997b position,
Baars once again shifts his position (to one different to that outlined in the body of his paper)
now stressing that, “In the view presented here, global access may be a necessary condition for consciousness; but in the nature of science we simply do not know at this time what would be the truly sufficient conditions.” (p308)
If global access is a necessary (but not sufficient) condition for consciousness, then global
access is causally antecedent to consciousness. However, if consciousness creates global
access, then consciousness is causally antecedent to global access. Baars tries to have it both
ways. Nor does he consider the three ways in which a process can be said to ‘be conscious’,
with their very different consequences for the functions of consciousness. Such confusions
illustrate the need to analyse the precise relation of conscious phenomenology to its
associated information processing with care. Phenomenal consciousness in humans is
unquestionably related to certain forms of information processing in humans. However
reductive redefinitions of consciousness in terms of the processing with which it is associated
impedes a clear analysis of how phenomenal consciousness actually relates to its associated
processing, thereby obscuring rather than clarifying its role in the economy of mind.
There is far more to be said about consciousness and its characteristics (see e.g. Velmans,
2009). However this brief, introductory paper is intended merely to deal with some
preliminary issues regarding how to approach and how not to approach its definition.
Hopefully, the above makes it clear that consciousness understood as phenomenal
consciousness provides a secure departure point for scientific and philosophical
investigations of its nature. Conversely, theories of consciousness that do not in some way
deal with its phenomenology are not theories of consciousness.
Maybe consciousness will ultimately be shown to be nothing more than a state or function
of the brain—and maybe it won’t. That is, after all, what much of the current debate is
about. But it is a mistake to define consciousness in a way that begs this question. It is a
mistake to claim that one is investigating phenomenal consciousness directly when one is
investigating its neural causes and correlates. And it is similarly a mistake to presume
phenomenal consciousness to be identical to the operations of some aspect of information
processing with which it is associated, for example the operations of a “global workspace.”
The mistake in these instances is one of premature closure. If one makes up one’s mind
about the ontology of phenomenal consciousness before fully investigating how its
phenomenology relates to processing in the brain and surrounding world, one precludes a
deeper understanding of that ontology. Conversely, no research is impeded by remaining
open.One can for example investigate the neural causal antecedents and correlates of given
conscious states whether one is a physicalist, a naturalistic dualist or a dual-aspect theorist.
Once a given reference for the term "consciousness" is fixed in its phenomenology, the
investigation of its nature can begin, and this may in time transmute the meaning (or sense) of
the term. As Dewey (1910) noted, to grasp the meaning of a thing, an event or situation is to
see it in its relations to other things—to note how it operates or functions, what consequences
follow from it, what causes it, and what uses it can be put to. Thus, to understand what
consciousness is, we need to understand what causes it, what its function(s) may be, how it
relates to non-conscious processing in the brain, and so on. As our scientific understanding of
these matters deepens, our understanding of what consciousness is will also deepen. A similar
transmutation of meaning (with growth of knowledge) occurs with basic terms in physics such
as "energy", and "time."
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