Consciousness 16 — A (Sorta) Brief History of Its Definitions

​(Quick Note: Sorry for the long delay on this. I am fine; no coronavirus infections yet. I posted the first 15 parts of this series roughly every other day, but it’s taken a little over a month now for this one. Basically, I’ve been doing loads of research. I had a sketch in mind for my personal thoughts about consciousness but fleshing out the details took a lot longer than I expected. I put together 37 pages of research for the first 15 posts in this series, but I had to gather another 80 pages (!) for these final posts, of which I expect there to be 8. Don’t let that put you off, though. The first 15 posts were basically transcriptions of that research, but these final ones will be highly summarized. Anyway, back to the series!)
 
In the last post, I went over what a scientific theory is and is not. I asked if we were ready for just such a scientific theory of consciousness, one that uses analogies from things we understand to explain everything we know, makes some predictions, and offers a consilient view of a wide variety of observations. Before fleshing out my own take on this, I knew I ought to take a little more care in reviewing the history of how other people have grappled with this big, tangled concept. Whole books have already been written about this, and I don’t intend to duplicate the details there, but a useful sketch can be drawn from the following sources that I found particularly helpful:
 

• the wikipedia entry on Consciousness
• the Stanford Encyclopedia of Philosophy entry on Consciousness
• a 2012 paper by the British philosopher Peter Hacker titled “The Sad and Sorry History of Consciousness: Being, Among Other Things, A Challenge to the ‘Consciousness-Studies Community'”
• three papers from Dan Dennett: “The Unimagined Preposterousness of Zombies” (1995); “Who’s on First? Heterophenomenology Explained” (2003); and “Darwin and the Overdue Demise of Essentialism” (2016)

 
I’ll use these sources and some details from the previous posts in this series to slot ideas about consciousness into three categories: philosophical, scientific, and dictionary.
 
Philosophical Considerations of Consciousness

• Descartes introduced the term ‘conscious’ into philosophy in 1640, although it was only in passing as part of his writing about thoughts. Descartes defined the term ‘thought’ (pensée) as “all that we are conscious as operating in us.” This included everything passing in our minds—thinking, sensing, understanding, wanting, and imagining. He held these things to be private, infallible, and beyond doubt, leading to his famous “I think therefore I am” argument (which is deeply flawed). Descartes was also a ‘substance dualist’ who asserted the existence of both physical and non-physical substances as components of nature. Such Cartesian dualism has largely been dropped from philosophy now.
• Fifty years later in 1690, John Locke is credited with the first modern concept of ‘consciousness’ which he defined as “the perception of what passes in a Man’s own Mind.”
• In 1714, Leibniz made the first distinction between ‘perception’ (“the representation of that which is outside”) and ‘apperception’ (“consciousness, or the reflective knowledge of this internal state”). Leibniz also famously argued that a mechanical explanation of consciousness would be impossible for it would be like going into a windmill and claiming the moving parts explained the phenomenon.
• In the 1780’s, Kant took these ideas to their “baroque culmination” by developing a rich structure of mental organisation. Kant called the components of this structure fundamental ‘intuitions’, which include 'object', ‘shape', 'quality', 'space', and 'time'. Kant’s category of ‘quality’ (aka qualia, e.g. redness, pain, etc.) has proven particularly difficult for philosophers to explain in physical terms. Some claim these ‘raw feels’ are ineffable and incapable of being reduced to component processes. There are psychologists and neuroscientists who reject this, however.
• “It was not until the middle of the nineteenth century that ‘consciousness’ came to be used to signify wakefulness as opposed to being unconscious. Thenceforth one could speak of losing and regaining consciousness.” (Hacker 2012)
• Phenomenology arose in the early 20th century in the works of Husserl, Heidegger, Sartre, and Merleau-Ponty. These phenomenologists studied the structures of consciousness as experienced from the first-person point of view. The experiences they considered ranged from perception, thought, memory, imagination, emotion, desire, and volition, to bodily awareness, embodied action, and social activity, including linguistic activity. This typically involved what Husserl called ‘intentionality’—the directedness of experience toward things in the world.
• In 1933 (The Physical Dimensions of Consciousness), the psychologist E. G. Boring originated the idea of ‘type-identity’ physicalism, aka the ‘identity theory of mind’. Boring wrote, “To the author, a perfect correlation is identity. Two events that always occur together at the same time in the same place, without any temporal or spatial differentiation at all, are not two events but the same event.” Several versions of this developed over the following decades but all share the central idea that the mind is identical to something physical.
• In 1949 (The Concept of Mind), Gilbert Ryle argued that traditional beliefs about consciousness were based on Cartesian dualism, which improperly separated minds from bodies. Ryle proposed we instead ought to talk about individuals acting in the world, and thus, ‘consciousness’ was not something separate from behaviour. (This paralleled B.F. Skinner’s behaviourism in psychology in the 1930’s.) As part of these arguments, Ryle coined the terms ‘ghost in the machine’ as well as ‘category mistake’. He provided robust distinctions between ‘knowing-how’ and ‘knowing-that’, as well as between ‘thin’ and ‘thick’ descriptions (i.e., observations only and providing context for them). Ryle also identified ‘topic-neutral terms’ such as ‘if’, ‘or’, ‘not’, ‘because’, and ‘and’. Ryle said his philosophical arguments “are intended not to increase what we know about minds but to rectify the logical geography of the knowledge we already possess.” Former Ryle student Daniel Dennett has said that recent trends in psychology such as embodied cognition and discursive psychology have provoked a renewed interest in Ryle's work.
• Two major schools in the philosophy of mind developed in the post-war years —representationalism and functionalism.
• Direct representationalism (aka naïve realism) argues that we perceive the world directly. Indirect realism/representationalism states that we do not and cannot perceive the external world as it really is; we can only know our ideas and our interpretations of the way the world is. This is roughly the accepted view of perception in the natural sciences.
• Functionalism was first put forth by Hilary Putnam in the 1960s. This theory of mind states that mental states (beliefs, desires, being in pain, etc.) are constituted solely by their functional role. It developed largely as an alternative to the identity theory of mind and behaviourism. An important part of some arguments for functionalism is the idea of ‘multiple realisability’, which asserts that mental states can be realised in multiple kinds of systems, not just brains.
• The term ‘folk psychology’ is used to characterise the human capacity to explain and predict the behaviour and mental state of other people. This has primarily focused on intentional states described in terms of everyday language rather than technical jargon, and includes concepts such as ‘beliefs’, ‘desires’, ‘fear’, and ‘hope’.
• Eliminative materialism is the claim that folk psychology is false and should be discarded (or eliminated). It is a materialist position in the philosophy of mind. Some supporters of eliminativism argue that no coherent neural basis will be found for many everyday psychological concepts such as belief or desire, since they are poorly defined. The main roots of eliminative materialism can be found in the writings of mid-20th century philosophers Wilfred Sellars, W.V.O. Quine, Paul Feyerabend, and Richard Rorty.
• In 1962 (“Philosophy and the Scientific Image of Man”), Wilfrid Sellars coined a distinction between the ‘manifest image’ and the ‘scientific image’ of the world. The manifest image includes intentions, thoughts, and appearances. The scientific image describes the world in terms of the theoretical physical sciences such as causality, particles, and forces. Sellars is also known for describing the task of philosophy as explaining how things, in the broadest sense of term, ‘hang together’.
• In 1974 (“What is it like to be a bat?”), Thomas Nagel published the paper that Dan Dennett called “the most widely cited and influential thought experiment about consciousness.” In it, Nagel defended three theses: 1) An experience is a conscious experience if and only if there is something it is like for the subject of the experience to have that very experience. 2) A creature is conscious or has conscious experience if and only if there is something it is like for the creature to be the creature it is. 3) The subjective character of the mental can be apprehended only from the point of view of the subject. Nagel used these theses to argue that “materialist theories of mind omit the essential component of consciousness.” (In my response to this thought experiment, I argued that it is actually entirely consistent with a materialist/physicalist worldview.)
• In 1980 (“Minds, Brains and Programs”), John Searle first published his Chinese Room thought experiment in which a man who does not understand Chinese, stays inside a room, takes in requests written in Chinese characters, consults a complete book for responses, and simply returns whatever characters the book tells him to. This experiment challenged the functionalist view that it is possible for a computer running a program to have a ‘mind’ and ‘consciousness’ in the same sense that people do, since this man would have no understanding of the Chinese function being performed. This was part of Searle’s ‘biological naturalism’ which states that consciousness requires the specific biological machinery that is found in brains. Searle argues that this machinery (known to neuroscience as the 'neural correlates of consciousness') must have some as yet unspecified 'causal powers' that give us our experience of consciousness. (In my response to this thought experiment, I noted that Searle’s dismissal of the notion that the Chinese Room ‘system’ gains consciousness chimes with what theoretical evolutionary biologists John Maynard Smith and Eros Szathmary said in The Origins of Life in their analysis of ecosystems (emphasis added): “There is a massive amount of information in the system, but it is information specific to individuals. There is no additional information concerned with regulating the system as a whole. It is therefore misleading to think of an ecosystem as a super-organism.” However, I also went through a list of behaviours that might give an AI system enough of the appearance of consciousness to get us to pragmatically treat it as if it did. Once computers become unique individuals that have changed their goals and understanding due to irreplaceable, learned experiences, then they will similarly attain the infinite value that any life has.)
• In 1982 (“Epiphenomenal Qualia”) and 1986 (“What Mary Didn’t Know”), Frank Jackson published and then clarified his ‘knowledge argument’ about a neuroscientist named Mary who learns “all there is to know” about the colour red while being confined to a black and white existence. Her discovery of ‘something new’ when she sees red for the first time is intended to show that consciousness must contain non-physical elements since she already supposedly knew every physical fact about red. (In my response to this thought experiment, I noted that a physical universe would preclude Mary from having every fact about red because mental imaginings are not enough to move the physical atoms in the nerves of our eyes and brain synapses.)
• In 1991 (Consciousness Explained), Dan Dennett put forward his ‘multiple drafts model’ of consciousness, claiming there is no single central place (a ‘Cartesian theatre’) where conscious experience occurs. Dennett's view of consciousness is that it is the apparently serial account of the brain's underlying parallelism. Dennett says that only a theory that explained conscious events in terms of unconscious events could explain consciousness at all. He says, “To explain is to explain away.”
• Robert Kirk first introduced the idea of philosophical zombies—unconscious beings who are physically and behaviourally identical to human beings—in 1974 (“Zombies v. Materialists”). However, this idea gained much more traction in the mid-1990’s with the publications of essays by Todd Moody (“Conversations with Zombies” 1994), Owen Flanagan and Thomas Polger (“Zombies and the Function of Consciousness” 1995), Dan Dennett (“The Unimagined Preposterousness of Zombies” 1995), and David Chalmers (The Conscious Mind 1996). If philosophical zombies existed, this would show that consciousness has non-physical properties. Robert Kirk eventually reversed his earlier position about zombies, but in 2019 wrote a Stanford Encyclopedia of Philosophy entry on zombies that ended by saying, “In spite of the fact that the arguments on both sides have become increasingly sophisticated—or perhaps because of it—they have not become more persuasive. The pull in each direction remains strong.” (In my response to this thought experiment, I noted that the argument takes our uncertainty about the existence of zombies and uses that to claim certainty that physicalism is false. That’s a logical error. We just don’t know yet and speculations about the possibility of zombies or zoombies (beings who are non-physically the same as zombies but are conscious) can actually be used to argue for or against physicalism in either direction.)
• In 1995 (“Facing Up to the Problem of Consciousness”), David Chalmers introduced the ‘hard problem’ of consciousness to ask why some internal states are subjective, felt states, rather than non-subjective, unfelt states, as in a thermostat or a toaster. Chalmers contrasted this with the ‘easy problems’ of explaining the neural basis for abilities to discriminate, integrate information, report mental states, focus attention, and so forth. Easy problems are (relatively) easy because “all that is required for their solution is to specify a mechanism that can perform the function.” The existence of the hard problem is controversial, with many philosophers and neuroscientists on both sides of the argument. (In an earlier post in this series, I said it is only hard because it can keep retreating to an impossible problem.)
• In 1996 (Consciousness and Experience), William Lycan argued that at least eight clearly distinct types of consciousness can be identified: 1) organism consciousness; 2) control consciousness; 3) consciousness of; 4) state/event consciousness; 5) reportability; 6) introspective consciousness; 7) subjective consciousness; and 8) self-consciousness.
• In 1998 (“On a Confusion About a Function of Consciousness”), Ned Block wrote that consciousness “is a mongrel concept: there are a number of very different ‘consciousnesses’.” In particular, Block proposed a distinction between two types of consciousness that he called phenomenal (P-consciousness) and access (A-consciousness). P-consciousness is simply raw experience: it is moving, coloured forms, sounds, sensations, emotions, and feelings with our bodies. These experiences can be called qualia. A-consciousness, on the other hand, is when information in our minds is accessible for verbal report, reasoning, and the control of behaviour. Information about what we perceive is access conscious; information about our thoughts is access conscious; information about the past is access conscious, and so on. Some philosophers, such as Daniel Dennett, have disputed the validity of this distinction. David Chalmers has argued that A-consciousness can in principle be understood in mechanistic terms but understanding P-consciousness is the hard problem.
• In 2003 (“Who’s on First? Heterophenomenology Explained”), Dan Dennett further elucidated the methodology used for studying consciousness, which he calls ‘heterophenomenology’ (the phenomenology of another, not oneself). Dennett says this is a straightforward extension of objective science that covers all the realms of human consciousness without having to abandon the experimental methods that have worked so well in the rest of science. Heterophenomenology is a way to take the first-person point of view as seriously as it can be taken. Social sciences are almost entirely conducted in this way already, so the methods are well understood. Consider two possible sources of data: (a) ‘conscious experiences themselves’ and (b) beliefs about these experiences. If you have conscious experiences you don’t believe you have, then those extra conscious experiences are just as inaccessible to you as to external observers. On the other hand, if you believe you have conscious experiences that you don’t in fact have, then it is your beliefs that we need to explain, not the non-existent experiences! Either way, this demonstrates the need to collect the data of (b), and those beliefs can be shared and studied objectively. In contrast, ‘lone-wolf autophenomenology’, in which the subject and experimenter are one and the same person, is a foul because it isn’t science until you turn your self-administered pilot studies into heterophenomenological experiments. Whatever insights one may garner from first-person investigations fall happily into place in third-person heterophenomenology. Heterophenomenology is, therefore, the beginning of a science of consciousness, not the end. And nobody has yet pointed to any variety of data that are inaccessible to heterophenomenology.
• Other philosophical explorations of consciousness talk of components such as:
  • Four main pieces: 1) knowledge in general; 2) intentionality; 3) introspection; and 4) phenomenal experience.
  • Streams of thought, as in the experience of thinking ‘in words’ or ‘in images’.
  • Creature consciousness—an animal, person, or other cognitive system may be conscious in a number of ways: sentience, wakefulness, self-consciousness, what it is like, subject of conscious states, or transitive consciousness (being conscious of).
  • State consciousness—there are six major options for distinct, though perhaps interrelated, types of this: 1) states one is aware of (meta-mentality); 2) qualitative states (raw sensory feels, qualia); 3) phenomenal states (not only sensory ideas and qualities but complex representations of time, space, cause, body, self, world, and the organized structure of lived reality); 4) what-it-is-like states (similar to 2 and 3, but coming from Nagel); 5) access consciousness (info generally available for use); and 6) narrative consciousness (serial episodes of a self).
• Current schools of philosophy about consciousness largely fall into two main camps: property dualism and physicalism.
• Property dualists assert the existence of conscious properties that are neither identical with nor reducible to physical properties, but which may nonetheless be made up of the same stuff as physical things. There are: 1) fundamental property dualists (consciousness is a basic part of the universe, much like fundamental physical properties such as electromagnetism); 2) emergent property dualists (consciousness arises in a radically new way from physical stuff, but only once it reaches a certain complexity); 3) neutral monist property dualists (physical and mental properties are both derived from something even more basic in reality); and 4) panpsychists (all parts of reality have both physical and mental properties).
• Physicalists assert that reality is only composed of physical objects and the fundamental forces acting upon them. There are: 1) eliminativists (the existence or distinction for some or all features of consciousness are denied in either modest or radical ways); 2) identity theorists (conscious properties just are physical processes, usually neurophysiological processes, and so no further causes or explanations are necessary). Most physicalists acknowledge the reality of consciousness but say that it supervenes on the physical, is composed of the physical, or is realised by the physical.
• In January 2020, when asked if he had a simple definition of consciousness, Dan Dennett said, “No. But that’s okay. That’s the way science works too. There’s no perfect definition of time or energy, but scientists get on with it.”

 
That’s obviously not everything written by philosophers about consciousness, but it’s a pretty good summary of the modern timeline. In my previous posts in this series, I already covered how some prominent scientists do “get on with” consciousness research, but let’s look at some of the main definitions used there.
 
 
Scientific Considerations of Consciousness

• In 1890 (The Principles of Psychology), William James wrote that introspection “means, of course, the looking into one’s own mind and reporting there what we discover” and the use of this inner sense is the way we become conscious. He said this inner sense is just like an outer sense, only: 1) without a sense organ; 2) its successful exercise is independent of observation conditions; 3) it never fails us, but always yields knowledge; and so therefore 4) we know the mind better than the material world. While some philosophers still seem beholden to such a Cartesian view of infallibility and indubitability, all four of these characteristics of consciousness have been shown to be faulty. James also considered the ways the unity of consciousness might be explained by known physics and found no satisfactory answer. He coined the term ‘combination problem’, in the context of a ‘mind-dust theory’ in which a full human conscious experience is proposed to be built up from proto- or micro-experiences in the same way that matter is built up from atoms. James claimed that such a theory was incoherent, since no causal physical account could be given of how distributed proto-experiences would ‘combine’. Today, some prominent philosophers and neuroscientists (e.g., Dan Dennett and Bernard Baars) disagree that this combination problem even exists, claiming consciousness is not unified in the way James described it. Evidence from recall experiments and change blindness support this.
• It was not known that neurons are the basic units of the brain until approximately 1900 (Santiago Ramón y Cajal). The concept of chemical transmission in the brain was not known until around 1930 (Henry Hallett Dale and Otto Loewi). In the 1950s, we began to understand the basic electrical phenomenon that neurons use to communicate—the action potential (Alan Lloyd Hodgkin, Andrew Huxley and John Eccles). We became aware of how neuronal networks code stimuli in the 1960s, which showed how the formation of concepts is possible (David H. Hubel and Torsten Wiesel). The molecular revolution swept through US universities in the 1980s. And it was only in the 1990s that molecular mechanisms of behavioural phenomena became widely known (Eric Richard Kandel).
• Starting in the 1980s, an expanding community of neuroscientists and psychologists have associated themselves with a field called ‘Consciousness Studies’. This created a stream of experimental work, which was published in books and journals such as Consciousness and Cognition, Frontiers in Consciousness Research, Psyche, and the Journal of Consciousness Studies. Regular conferences were also organised by groups such as the Association for the Scientific Study of Consciousness, and the Society for Consciousness Studies.
• Seven types of specific detailed theories have emerged from Consciousness Studies about the nature of consciousness. This is not comprehensive, but it helps to indicate the main range of options. They are: 1) higher-order theories, 2) representational theories, 3) interpretative narrative theories, 4) cognitive theories, 5) neural theories, 6) quantum theories, and 7) nonphysical theories. These are described below.
• 1. Higher-order (HO) theories analyse the notion of a conscious mental state in terms of reflexive meta-mental self-awareness. Unconscious mental states are unconscious precisely because we lack higher-order states about them.
• 2. Representational theories attempt to explain the various phenomena of consciousness in terms of representation. A mental representation is a hypothetical internal cognitive symbol or process that represents external reality. Mental representation is the mental imagery of things that are not actually present to the senses. A mental representation is one of the prevailing ways of explaining and describing the nature of ideas and concepts. Mental representations enable representing things that have never been experienced as well as things that do not exist. Although visual imagery is more likely to be recalled, mental imagery may involve representations in any of the senses.
• 3. According to narrative interpretive theories, consciousness is dependent on interpretative judgments. Dan Dennett’s ‘Multiple Drafts Model’ is a prominent example of this. MDM says that at any given moment many types of content are being generated throughout the brain. What makes some of these contents conscious is not that they occur in a privileged spatial or functional location—the so called ‘Cartesian Theatre’—but, rather, it is a matter of what Dennett calls ‘cerebral celebrity’. MDM says the self emerges from the roughly serial narrative that is constructed out of the various contents in the system.
• 4. Cognitive theories associate consciousness with a distinct cognitive architecture or a special pattern of activity within that structure. For example, Global Workspace Theory describes consciousness in terms of a competition among processors and outputs to ‘broadcast’ information for widespread access and use.
• 5. Neural theories of consciousness come in many forms, though most in some way concern the so called ‘neural correlates of consciousness’ or NCCs. A sampling of recent neural theories includes models that appeal to:
  • global integrated fields (Kinsbourne)
  • binding through synchronous oscillation (Singer 1999, Crick and Koch 1990)
  • NMDA channels in neurons (Flohr 1995)
  • patterns of cortical activation modulated by the thalamus (Llinas 2001)
  • re-entrant cortical loops (Edelman 1989)
  • comparator mechanisms that engage in continuous action-prediction-assessment loops between frontal and midbrain areas (Gray 1995)
  • left hemisphere based interpretative processes (Gazzaniga 1988)
  • emotive somatosensory hemostatic processes based in the frontal-limbic nexus (Damasio 1999) or in the periaqueductal gray (Panksepp 1998)

It is possible for several of these to be true, with each contributing some partial understanding to the links between all the diverse forms of consciousness and the brain activity that occurs in many different levels of complex organization and structure.

• 6. According to quantum theories, the nature and basis of consciousness cannot be adequately understood within the framework of classical physics but must be sought within the alternative picture of physical reality provided by quantum mechanics.
• 7. Those who reject physicalist descriptions of consciousness look for ways of modelling it as a non-physical aspect of reality. For example, David Chalmers (1996) has offered an admittedly speculative version of panpsychism which appeals to the notion of information not only to explain synchrony between psycho and physical events, but also to possibly explain the existence of the physical itself as derived from information (i.e., an “it from bit” theory).
• Dr Ginger Campbell, host of the Brain Science podcast, notes that while theories of consciousness do have their differences, there are still three concepts that the most prominent scientific ones all share: 1) consciousness requires a brain; 2) consciousness is a product of evolution; and 3) consciousness is embodied.
• The ‘Global Neuronal Workspace Theory’ states that consciousness is global information broadcasting within the cortex.
• Antonio Damasio defines consciousness as: mind + self. To him, a ‘mind’ emerges from the brain when an animal is able to create images and to map the world and its body. Consciousness requires the addition of self-awareness. This begins at the level of the brain stem, with ‘primordial feelings’. The ‘self’ is built up in stages starting with the proto-self made up of primordial feelings, affect alone, and feeling alive. Then the core self is developed when the proto-self can interact with objects and images such that they are modified and there is a narrative sequence. Finally comes the autobiographical self, which is built from the lived past and the anticipated future.
• Feinberg and Mallatt say their theory of ‘Neurobiological Naturalism’ rests on three principles: 1) life—consciousness is grounded in the unique features of life; 2) neural features—consciousness correlates with neural activity; and 3) naturalism—nothing supernatural is needed. To F&M, the defining features of consciousness are organised in three levels. Level 1) General Biological Features—life, embodiment, processes, self-organising systems, emergence, teleonomy, and adaption. Level 2) Reflexes of animals with nervous systems. Level 3) Special Neurobiological Features—complex hierarchy of networks, nested and non-nested processes (aka recursive), isomorphic representations, mental images, affective states, attention, and memory.
• Joseph LeDoux prefers higher-order representations from among the different theories of consciousness. LeDoux seems to draw a pretty narrow definition around consciousness, but then shows the clear evolutionary history of aspects of consciousness along the way, and really advocates for a more subtle use of the term.
• Michael Graziano sees a growing standard model of consciousness whose core set of scientists realise that we are machines and the brain is an information processing machine that thinks it has magic inside it because it builds somewhat imperfect models of the world inside it. This brings together Higher Order Thought Theory, Global Workspace Theory, and even some Illusionists who talk of consciousness as an illusion. His ‘Attention Schema Theory’ attempts to provide an integrative picture of these.
• Integrated Information Theory says fundamentally what consciousness is, is the ability of any physical system to exert causal power over itself. This is an Aristotelian notion of causality. For example, the present state of my brain can determine one of the trillion future states of my brain. One of the trillion past states of my brain can have determined my current state, so it has causal power. The more power the past can exert over the present and future, the more conscious the thing that we are talking about is.
• These neuroscientific theories can be summed up into two main camps: global and local.
• Global theories describe modules for: balance and coordination; memory; emotion; language; writing; attention, planning, organization, and reasoning; emotional affect and adaptability; motor / sensory; listening and decoding; reading and interpretation; visual-spatial and visual recognition. There may be specific pathways through each of these modules, e.g. dorsal visual stream, but for general connection between multiple modules there may also be a global workspace. This global workspace coordinates inputs from evaluative systems (value), attentional systems (focusing), long-term memory (past), and perceptual systems (present), into motor control outputs (future). Information in the global workspace is available from all modules and can be seen by each module.
• Local theories say vision, for example, just needs to trigger the right kind of activity patterns in the visual module to be consciously perceived. (E.g. Victor Lamme’s local recurrence theory.) Activity that is forward-focused only (from stimulus to response) is unconscious. Feedback activity is required for consciousness. One thing common to all local theories is they say that “activity in frontal and parietal cortices is not absolutely needed for conscious perception to occur.”

 
Phew! That is a heck of a lot of history and detail about this subject.
 
So, what is consciousness?
 
We still can’t say! And from all of this, you can probably see why there are still so many different dictionary definitions of consciousness. Let’s add them to the list of this research too.
 
Dictionary Definitions of Consciousness

• (Wikipedia)—the English word ‘conscious’ originally derived from the Latin conscius (con- ‘together’ and scio ‘to know’), but the Latin word did not have the same meaning as our word, it meant ‘knowing with’ or ‘having joint or common knowledge with another’
• (Diderot and d'Alembert's 1753 Encyclopédie)—the opinion or internal feeling that we ourselves have from what we do
• (The Oxford Living Dictionary)—the state of being aware of and responsive to one's surroundings; a person's awareness or perception of something; the fact of awareness by the mind of itself and the world
• (Cambridge Dictionary)—the state of understanding and realizing something
• (Merriam-Webster)—awareness or sentience of internal or external existence
• (Webster's Third New International Dictionary)—1) awareness or perception of an inward psychological or spiritual fact; intuitively perceived knowledge of something in one's inner self; inward awareness of an external object, state, or fact; concerned awareness: interest, concern—often used with an attributive noun; 2) the state or activity that is characterized by sensation, emotion, volition, or thought; mind in the broadest possible sense; something in nature that is distinguished from the physical; 3) the totality in psychology of sensations, perceptions, ideas, attitudes, and feelings of which an individual or a group is aware at any given time or within a particular time span

 
Finally, I want to note the hierarchy of consciousness that Mike Smith (aka Self Aware Patterns) has developed from his very extensive reading about all of this. To him, consciousness involves:

1. reflexes and fixed action patterns
2. perceptions, representations of the environment, expanding the scope of what the reflexes are reacting to
3. volition, goal directed behaviour, allowing or inhibiting reflexes based on simple valenced cause and effect predictions
4. deliberative imagination, sensory-action scenario simulations assessed on valenced reactions
5. introspection, recursive metacognition, and symbolic thought.

 
Brief Thoughts
So, attributions of consciousness stretch all the way from it being something as small as the private, ineffable, special feeling that only we rational humans have when we think about our thinking, right on down to it being a fundamental force of the universe that gives proto-feelings to an electron of what it’s like to be that electron. Wow. What a mess. As the Wikipedia entry on consciousness notes:
 
“The level of disagreement about the meaning of the word indicates that it either means different things to different people, or else it encompasses a variety of distinct meanings with no simple element in common.”
 
The Stanford Encyclopedia of Philosophy entry on consciousness comes to a similar conclusion:
 
“A comprehensive understanding of consciousness will likely require theories of many types. One might usefully and without contradiction accept a diversity of models that each in their own way aim respectively to explain the physical, neural, cognitive, functional, representational, and higher-order aspects of consciousness. There is unlikely to be any single theoretical perspective that suffices for explaining all the features of consciousness that we wish to understand. Thus, a synthetic and pluralistic approach may provide the best road to future progress.”
 
Once again, however, I am drawn to use the ‘universal acid’ of evolutionary thinking that Dan Dennett described in his 1995 book Darwin’s Dangerous Idea. If anything stands a chance to usefully provide “a single theoretical perspective” on consciousness, I think it’s likely to be that. For a helpful start, consider these passages from Dennett’s 2016 paper “Darwin and the Overdue Demise of Essentialism.”
 
“Ever since Socrates pioneered the demand to know what all Fs have in common, in virtue of which they are Fs, the ideal of clear, sharp boundaries has been one of the founding principles of philosophy.”
 
“When Darwin came along with the revolutionary discovery that the sets of living things were not eternal, hard-edged, in-or-out classes but historical popula­tions with fuzzy boundaries, the main reactions of philosophers were to either ignore this hard-to-deny fact or treat it as a challenge: Now how should we impose our cookie-cutter set theory on this vague and meandering portion of reality?”
 
“We should quell our desire to draw lines. We can live with the quite unshocking and unmysterious fact that there were all these gradual changes that accumu­lated over many millions of years.”
 
“The demand for essences with sharp boundaries blinds thinkers to the prospect of gradualist theories of complex phenomena, such as life, intentions, natural selection itself, moral responsibility, and consciousness.”
 
Indeed. So, we’re looking for a gradualist theory of the complex phenomena of consciousness. We’ve got a pretty good idea of what we’re looking for, based on all the definitions from philosophers, scientists, and dictionaries shown above, but it could be anywhere, and it could have got started at any time. To really spot an emergence and development of consciousness, in order to try to then characterise it, we’ll have to look at the history of everything that has ever existed. So, I’ll give that a go in the next post. That shouldn’t take too long.

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Previous Posts in This Series:
Consciousness 1 — Introduction to the Series
Consciousness 2 — The Illusory Self and a Fundamental Mystery
Consciousness 3 — The Hard Problem
Consciousness 4 — Panpsychist Problems With Consciousness
Consciousness 5 — Is It Just An Illusion?
Consciousness 6 — Introducing an Evolutionary Perspective
Consciousness 7 — More On Evolution
Consciousness 8 — Neurophilosophy
Consciousness 9 — Global Neuronal Workspace Theory
Consciousness 10 — Mind + Self
Consciousness 11 — Neurobiological Naturalism
Consciousness 12 — The Deep History of Ourselves
Consciousness 13 — (Rethinking) The Attention Schema
Consciousness 14 — Integrated Information Theory
Consciousness 15 — What is a Theory?