09 April 2013

What is Consciousness Anyway?

I'm often frustrated by simplistic worldviews, especially when I fall into one myself. A couple of years back I wrote a response to the charge that is frequently levelled at me, namely that I am a materialist (gasp!). The choices in these cases seem to be materialist or non-materialist (where the latter involves believing in a range of supernatural entities and forces). Similarly there seems to be an assumption that if one is a materialist that one considers consciousness to be a mere epiphenomena. The suggestion is often that if you don't think that consciousness is an ineffable supernatural entity then you must believe it to be mere epiphenomena. But these are not the only two choices. 

A related subject is the idea that science can and does tell us nothing about consciousness. This is clearly not true, as scientists who study the mind are able to tell us a great deal about it. The idea that science cannot explain consciousness seem to be rooted in particular views rather than based on familiarity with scientific inquiry. In other words it's just an ideological position.

I don't think scientists have fully explained consciousness by any means, but there are some very interesting observations of, and ideas about, the mind, and a lot of really insightful deductive work on how the mind must function in order to exhibit the features it does (aka reverse engineering). At present we have some interesting conjectures about how the mind might work that are guiding our search for more data. Scientists are busy trying to disprove one theory or another.

Now, I happen to be a fan of info-graphic guru David McCandless and recently bought a copy of his book Information is Beautiful. One of his infographics lists 12 explanations for consciousness (including a Buddhist version). Each is represented by a graphic and a sentence. The same information with animations is online here. (At time of writing they are conducting a survey of opinions about consciousness using this set). Below is his set of 12 with a couple of additions. The heading in bold and the summary in italics come from McCandless. I have added a few explanatory comments in each case.

Substance Dualism
Consciousness is a field that exists in its own parallel "realm" of existence outside reality so can't be seen.
Aka Cartesian Duality. Strict separation between mind and body. Consciousness and matter are two distinct types of substance. The problems with this view are legend and almost no one takes it seriously any more. Still, if you believe in ghosts or psychic powers then you have a foot in this camp!

Substance Monism
The entire universe is one substance, 
All is one, dude. Included in this is the form of idealism which says that everything is the mind, and physical objects don't really exist. Buddhists sometimes flirt with idealism e.g 'mind only' cittamātra. The opposite extreme, which is more popular in the West is that everything is just material, which is covered by epiphenomenalism, behaviourism and functionalism.

Emergent Dualism
Consciousness is a sensation that "grows" inevitably out of complicated brain states.
This features in a common science fiction theme: a computer network becomes so complex that it spontaneously develops consciousness. As a philosophy of mind this view relies on observations about complex systems emerging from simpler units interacting. One of the central insights of work on fractals and complexity theory is that simple repeating units can produce patterns and processes of startling complexity. The view accepts that we are constructed from matter, but argues that complex arrangements of matter are capable of displaying properties which are greater than the sum of their parts - consciousness and even a soul are attributable to this by proponents.

Property Dualism
Consciousness is a physical property of all matter, like electromagnetism, just not one the scientists know about.
Science is making new discoveries all the time right? So why should we assume that all the properties of matter have been discovered yet? The idea here is that everything is made of one substance, matter, (and it is  thus a form of substance monism) but that matter has multiple properties. In particular matter has physical properties and mental properties. In this view all matter has a psychic component.

This is similar to the Jain view of the world which considered that everything was conscious. Consciousness exists in a hierarchy depending on how many senses the entity possesses. Rock only has the sense of touch, so is only minimally conscious. Some animals have more or different senses than we do.

As a way around both materialism and idealism this view has some merits.

Pan Psychism
All matter has a psychic part. Consciousness is just the psychic part of our brain.
This seems to be a popular view amongst my colleagues. Sometimes its described in terms of the brain being like an radio that 'picks up' consciousness and tunes it in so we can be aware of it. Not very different from property dualism, indeed it is sometimes called Panpsychic property dualism. However Pan Psychism treats everything as mind, where mind has physical and mental properties. As I understand it Theravāda Abhidhamma sees the world in this way. Many Buddhists argue that in our world mind creates the physical world, possibly on the basis of the Nidāna sequence in which viññāna is the condition for nāmarūpa.

Identity Theory
Mental states are simply physical events that we can see in brain scans.
Aka type physicalism or reductive materialism. In this view the states and processes of the mind are identical to states and processes of the brain. In other words what you think of as your consciousness is simply the physical states of the brain. This is a form of monism - it doesn't see the mind as substantially different from the brain. 

Functionalism

Consciousness and its states (belief, desire, pain) are simply functions the brain performs.
Consciousness is the sum of the functions of the brain. Mental states are constituted solely by causal relations to other mental states, sensory inputs, and behavioural outputs. Presumably this does away with the hard problem of consciousness? Functionalism has it's origins in Aristotle's idea of a soul: that it is just that which enables us to function as a human being. Functionalism can be thought of as behaviourism as seen through the lens of cognitive psychology.

Behaviourism

Consciousness is literally just behaviour. When we behave in a certain way, we appear conscious.
Once a very popular view behaviourism dispenses with the idea of consciousness. Life is just stimulus and response. In higher animals such as humans this is so complex that it appears to be consciousness, but really it isn't. This kind of mechanistic thinking about humans was popular early in the Enlightenment period when clockwork was the complex mode. I associate behaviourism with the advent of computers. The mind is often likened to the most complex human creation of the moment. Cavemen no doubt thought of the mind as a flint knife. When computers came along as they seemed like a metaphor for the mind. But in practice computers work very differently from the mind. However the invention of neural networks showed that it is possible to imitate more closely how the human mind works. This is the subject of one of De Bono's lesser known works: I am Right You Are Wrong (which I recommend).

Epiphenomenalism

Consciousness is an accidental side effect of complex physical processes in the brain.
This is the view that seems to get Buddhists most steamed up. Another form of mechanistic thinking which down plays the hard problem of consciousness by denying that anything is going on. "Move along folks, there's nothing to see here." It arose out of attempts to get around mind/body dualism.

If this view were to hold then we ought to be able to build a sufficiently complex clockwork device that was indistinguishable from a conscious being.

Quantum Consciousness
Not sure what consciousness is, but quantum phsyics over classical physics, can better explain it.
There is no reason why the mind should not involve quantum phenomena. But there is no evidence that it does. For some time it has been trendy to invoke quantum mechanics as an explanation for all sorts of things. But those attempting this seem to be philosophers rather than quantum theorists (Dennett for instance) and I'm doubtful. I've attempted to debunk the idea that Buddhism has anything in common with quantum mechanics (see Erwin Schrödinger Didn't Have a Cat).

100 billion cells each with 1000 connections is really very complex, so I don't see an a priori need to invoke quantum mechanics in order to explain or describe consciousness. On the other hand the adaptability of an amoeba might make us think again since it is capable of remarkably sophisticated responses to its environment given its relative simplicity of form. However until there's actual evidence of quantum effects this remains in the realm of speculation. Maybe someone more familiar with Dennett can point to the evidence that he cites?

Cognitivism

Consciousness is the sensation of your most significant thoughts being highlighted
Quite a lot in common with Functionalism, in that it uses insights from cognitive psychology to improve on Behaviourism. In a sense it highlight thinking as a distinct kind of behaviour. It incorporates the idea of the mind as a computer which processes information and produces behaviour (Behaviourism only acknowledges behaviour).

Higher Order Theory

Consciousness is just higher order thoughts (thoughts about other thoughts)
The approach emerges from the understanding that there are different types of thoughts, and that they operate at different levels of organisation. One of the basic distinctions being between unconscious perception and conscious perception. Another is between intransitive consciousness (mere consciousness) and transitive consciousness (consciousness of some object). Distinctions amongst philosophers of mind often depend on finding the right level at which to describe it. Higher Order  Theory is primarily concerned with understanding conscious, transitive mental states (in this it is similar to early Buddhism).

Buddhism(?)
Consciousness is a continuous stream of ever-recurring phenomena, pinched, like eddies, into isolated minds.
Clearly McCandless is not that well informed on Buddhist ideas about consciousness, and since he doesn't cite sources we can't get at why he thinks we think like this. The last part sounds more like Hinduism to me.

Early Buddhism 
Consciousness is always consciousness of... 
If consciousness is even a subject of inquiry (and I'm not convinced it is) then the usual way of talking about it is that consciousness arises when sense object meets sense faculty and gives rise to sense consciousness.  Early Buddhism focusses on transitive consciousness and has almost no interest in the mind otherwise. The word being translated as 'consciousness' is viññāna which probably means some more like cognition or awareness. Such a cognition which arises in dependence on conditions is referred to as conditioned (saṅkhata); it can be analysed into five branches (pañcakhandhā ≡ papañca). It is possible to have unconditioned (asaṅkhata) cognition when one sees and knows mental objects (dhammā) as they are (yathābhūta-ñānadassana). It is claimed that the six senses (eye, ear, nose, tongue, body, mind) and their objects make up the totality (sabbaṃ) and that any other proposition about the world is beyond the proper domain (visāya) of inquiry.

Late Buddhism
Consciousness is a manifestation of karmic seeds
Consciousness arises on the basis of a storehouse for the 'seeds' of karma (ālayavijñāna). Floating on top of this layer are the sensory cognitions which produce provisionally valid cognitions (relative truth). The extra layer at the bottom was invented to try to account for difficulties explaining rebirth (the problem of continuity of consequences). However the ālayavijñāna is a kind of permanent substrate and thus suffers from metaphysical problems related to eternalism. I argue that the problem of continuity between births cannot be practically solved without positing some kind of ātman.

Representationalism

Damasio's Model of Consciousness
This is a rubric for ideas in which consciousness is an emergent property of the brain's role of monitoring the environment and the body's own internal states using virtual representations created in the brain. Combined with temporal memories of previous states (memory), and projections of futures states (imagination) and representing the observing subject as a virtual self, consciousness is the overall effect of these functions. This emerges particularly from the work of Antonio Damasio and Thomas Metzinger and is closest to my own understanding of what consciousness is or does.

Comments

Of course it must be said that all of these are the thinnest of glosses on some quite complex ideas, and that not being expert in any of them I have probably got them wrong. My purpose here is mainly to represent the complexity of the subject matter and encourage readers to take in some of the options that are available. There are more than two choices. Being interested in the science of the mind and uninterested in the supernatural leaves me choices other the epiphenomenalism.

In trying to understand McCandless's categories it becomes obvious that many of them have substantial cross-over. Some are in fact subsets of broader categories. So I wouldn't put too much store by his list. It illustrates the point that there are a lot of theories, but not much more.

It seems to me that if we are to make any progress in understanding ourselves then we need to begin with observation and allow understanding to emerge. My beef with philosophy is that it starts with theories and searches for facts to fit. Indeed the vast legacy of philosophical speculation of the mind completely divorced from observation would seem to be a major impediment to progress.

My enthusiasm for Thomas Metzinger is precisely that he starts with observations and works towards an explanation. I'm also interested George Lakoff's ideas about categorisation, metaphor and embodied cognition influence how we see cognition and selfhood. Lakoff's work also stems from observation. I don't mind being presented with a worked out theory as long as the evidence for and against the theory follows.

I tend towards rejecting any strong form of mind/body dualism. Free floating, disembodied consciousness simply does not make sense to me. All the evidence I am aware of points to an intimate connection between brain and consciousness. Metzinger's account of his out of body experiences is central to undermining the last vestiges of my dualistic thinking in this area because it showed that unusual phenomena, like religious traditions, don't have to be taken on face value. Yes, it really does seem as if the consciousness can leave the body; but no, it doesn't have to literally do so to produce a convincing illusion. Traditional Buddhist ideas about consciousness are compatible with this view, as long as we are not too literalistic.

With Kant I accept the existence of an objective world distinct from my perception of it along with the caution that we can only infer things about this world, we can never know it directly (since our only source of information about the world is our senses). However this is not a problem in the foreground of early Buddhist thought. The objective world is a given in early Buddhist texts. Our experience of the world occurs in the space of overlap between a sense endowed body, a world of objective, and attention to the overlap. The entire focus of early Buddhist practice takes place in this liminal space, where our responses to experience feedback into, and to some extent determine, the quality of our experience.

One of the main criticisms that comes from the anti-physicalist side of the argument is that theories which don't accept a supernatural aspect to mind, i.e. an aspect of mind which operates outside the known laws of nature, can't account for qualia. One of the reasons this claim stands is that such people do not keep up with neuroscience. Some recent research looks promising.
Orpwood, Roger. 'Qualia Could Arise from Information Processing in Local Cortical Networks.' Frontiers in Psychology. 2013; 4: 121. Published online 2013 March 14. doi:10.3389/fpsyg.2013.00121
Jakub Limanowski, and Felix Blankenburg. 'Minimal self-models and the free energy principle.' Frontiers in Human Neuroscience. 2013; 7: 547. Published online 2013 September 12. doi: 10.3389/fnhum.2013.00547

See also
 The Where of What: How Brains Represent Thousands of Objects by Ed Yong (Dec 2012), which summarises the state of research on this subject as of 2012. 
I also recommend A Brain in a Supercomputer, a TED talk by Henry Markham which helps with getting an idea of the complexity of the brain. Follow this up at The Blue Brain Project.
We do not yet fully understand consciousness. But this is no reason to fall back on supernatural explanations.
The route away from superstition and fearful projections onto the world has been long and difficult but it has been worth it. On the other hand what we are learning is far more sophisticated than Medieval insights from Buddhists and if we stick to what's in our ancient texts at some point we'll become irrelevant. The Mindfulness Therapy movement is already showing how this this might work since they have been far more successful in communicating their version of Buddhist methods in a shorter space of time.

~~oOo~~

See also this in the Guardian (10.4.13): Transparent brains reveal their secrets – video. A fly-through of a whole mouse brain where the non-neuronal material has been rendered transparent - every dendrite of every neuron is visible! Selective stains enable neurons of different functionality to be coloured differently. The original article is: Chung, K.,  et al (2013). 'Structural and molecular interrogation of intact biological systems.' Nature. doi:10.1038/nature12107.

I should also have given a nod to the Human Connectome Project. No doubt this new technique used above will advance their work considerably.


Brain as Receiver

One of the options that comes up regularly to explain consciousness in a dualistic frame is the brain as TV receiver analogy. This is ruled out by Steven Novella. He argues that to compare the brain to a TV that simply displays the information beamed into it the analogy would have to answer these questions positively:
A more accurate analogy would be this – can you alter the wiring of a TV in order to change the plot of a TV program? Can you change a sitcom into a drama? Can you change the dialogue of the characters? Can you stimulate one of the wires in the TV in order to make one of the on-screen characters twitch?
Disrupting the reception, via brain damage, does not simply distort the image of the show, it changes the plot and the characters. The brain simply cannot be a passive receiver. The brain creates consciousness. This is the only way to explain the correlations. 
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