Grokking the Hard Problem of Consciousness
By Robert H. Clark
(This is a guest essay. The opinions expressed as those of its author.)
|Illustration of a synapse (from the book Why Materialism Is Baloney).|
I think one can get a visceral, intuitive sense of how, what is often referred to as "the hard problem of consciousness," actually is "the impossible problem of consciousness," through a simple, thought experiment. Note that in this piece I am going to be using the following words interchangeably: mind, consciousness and you.
But first a reminder that "the hard problem" refers to the question of how the physical processes of your brain create consciousness: your self-awareness, the flow of your thoughts, feelings, and experiences, the totality of your subjective experience, i.e. YOU. This problem is considered by many to be not just a hard problem but the hard problem confronting science, because of the disconcerting but simple fact that there is nothing about the physical activity of the constituent particles of your brain, at any level of organization you choose to examine them, cellular, molecular, subatomic, etc., from which the qualities of subjective experience can be directly derived.
Not only is there nothing remotely like a flowchart in some neuroscience textbook, displaying a sequence of discrete, material steps or processes, describing a smooth transition from physical processes to you; "The hard problem" is one of the very few problems in science, for which there is not even, the beginnings, of an inkling, of a clue, of what a progression of causality from meat to self-awareness might look like. Forget theories, forget hypotheses, after over one hundred years of research, attempts to think about and then elucidate explanatory ideas about this progression of causality amount to vague notions that often reveal more about the limitations of language than "the hard problem" itself.
Think about this for a moment. For many phenomena in nature, scientists can with some confidence project that it is only a matter of time before they can reductively chip away at understanding how one physical process leads to the next, which in turn leads to better ideas about what the next sequence of physical processes will be, et cetera, right along the chain of causation until they get to the thing they are trying to understand. Most things science has described have a fairly clear, contextual place in the map of reality that has so far been worked out, all linked together in a vast network of things and causation. It is not an exaggeration to say that, consciousness exists outside this map. Roads that seem to lead there come to an abrupt cliff far from the final destination.
So Where Do Scientists Think Consciousness Comes From?Here are brief descriptions of the three predominant working ideas, (at least among the dominant group of materialist scientists who believe that mind arises from and is completely contained in your physical brain), about where you come from.
The first is that you don’t really exist. In this view, you may think you are aware of yourself reading this as you, but you are not really, it’s just an illusion. Consciousness is an illusion. A major proponent of this view is philosopher Daniel Dennett.
The second is that brain activity is consciousness. This is often summarized with phrase "Mind is what brain does." What does this mean exactly? Well proponents don't seem to know either. Here is Dr. Susan Blackmore from her recent post Correlation is not a cause (undated) on Edge.org.
At the moment we have no inkling of how consciousness could be brain activity but my guess is that it will turn out that way. Once we clear away some of our delusions about the nature of our own minds, we may finally see why there is no deep mystery and our conscious experiences simply are what is going on inside our brains.If these two positions seem incoherent to you, maybe you will like the third and probably most mainstream notion, Emergentism. This is the idea that mind emerges from the physical activity of the brain. To quote the Wikipedia entry linked to above:
A property of a system is said to be emergent if it is in some sense more than the "sum" of the properties of the system's parts. An emergent property is said to be dependent on some more basic properties (and their relationships and configuration), so that it can have no separate existence.Unfortunately while every other emergent property known in nature, can be deduced directly as a consequence of the physical processes from which it emerges, with consciousness that is not the case. There is the physical activity of the brain, and then there is you, and in between there is a bottomless conceptual and evidential chasm.
Why do these three main ideas inform neuroscience, because they are the only possible choices allowed for a priori within the materialist paradigm, where nothing by definition, can exist outside the matter and energy fields that comprise the totality of reality, including mind. Current neuroscience research is hobbled by this dogma that the brain must produce mind regardless of any evidence to the contrary. Think about these three ideas after you go through the thought experiment.
Your BrainOk, we are just about to dive into our thought experiment, but first I suggest you read this short explanation of how our brains actually work. Trust me it will make the thought experiment that much more illuminating. This passage is excerpted from Why Materialism is Baloney by Bernardo Kastrup, which presents an excellent counter-narrative to both Materialism and Theism that I highly recommend if you wish to explore this topic further.
A very brief introduction to neuroscience
Before continuing our discussion we need a little more background on how the brain works. Although neuroscience is a complex discipline, its fundamentals are surprisingly simple. After you read the following few paragraphs you will have a fairly good overview of what happens inside your head. It’s simpler than you might suppose and anybody can understand it with little effort, irrespective of background. Moreover, these simple fundamentals will be more than sufficient for you to understand the rest of this chapter. All I ask of you is focused attention for the remainder of this short section.
Here we go. The brain is composed of two main types of cells: neurons and glial cells. Neurons do the actual work of processing information, while glial cells perform support functions like insulation, structural and metabolic support, etc. For the purposes of this book, we can ignore the glial cells and focus solely on neurons.
Each neuron is composed of three main parts: the neuron’s body, the dendrites and the axon. See Figure 1. The neuron’s body is the main part of the cell, responsible for coordinating all of the neuron's activities. The dendrites are extensions of the neuron's body that contain many branches. The axon is a long, thin, cable-like projection that extends far from the neuron's body so to connect it to other neurons. The tip of the axon typically branches out into several terminals.
The brain is basically a giant network of interconnected neurons. Roughly speaking, the axon of a given neuron connects, through its multiple branching terminals, to dendrites of many other neurons. See Figure 1 again. The point where an axon terminal meets a dendrite is called a synapse. The terminal and the dendrite don’t actually touch: a tiny gap remains in between them, which is called a synaptic cleft.
Here is how the whole thing operates: the body of a neuron generates an electric charge. The axon of the neuron carries this electric charge all the way to its terminals. If and when the electric charge grows strong enough to cross a certain threshold, it triggers the release of certain chemicals at the terminals, which are called neurotransmitters. When this happens, the neuron is said to have fired. The neurotransmitters released then drift across the synaptic cleft and stimulate the dendrites of the neuron on the other side of the cleft by fitting into chemical receptors. This is also illustrated in Figure 1. The corresponding stimulus can be an excitatory one – causing the other neuron to increase its own electric charge – or an inhibitory one – causing the other neuron to reduce its electric charge – depending on the neurotransmitter released.
Whether a given neuron fires or not – that is, whether it releases neurotransmitters or not – is thus determined by how many other neurons connected to its dendrites are firing or not, and by what type of neurotransmitters – inhibitory or excitatory – they release when they do fire. A neuron only fires when it has been stimulated with enough excitatory neurotransmitters released by other neurons and provided that it has not been too inhibited by inhibitory neurotransmitters. The entire process has electric aspects – namely, the buildup of electric charge – and chemical aspects – namely, the release of neurotransmitters. We thus say that the brain operates on the basis of electrochemical processes.
A neural network is basically a set of neurons connected together, through synapses, according to some network topology. There can be huge chains of interconnected neurons in the brain: neurons connected to other neurons, which in turn are connected to other neurons, and so on. These networks can also contain closed cycles, whereby a neuron at the end of a chain connects back to a neuron at the beginning of the chain. The brain can be seen as a superset of many neural networks.
Brain activity is associated with the firings of neurons in a neural network. Though there are many neurons in a network, typically only a subset of them is actually firing when observed. Neuroscientists can scan a living brain and see which subset of a neural network is actually active. We call each one of these active subsets a neural process. As we will see below, conscious experience correlates with certain neural processes in the brain, which are then called the neural correlates of consciousness. Naturally, neural processes can be excitatory or inhibitory, depending on whether the neurotransmitters they release respectively increase or decrease the electric charge of connected neurons.
That’s it. Not too difficult, was it?"
Bernardo Kastrup, "Why Materialism Is Baloney: How true skeptics know there is no death and fathom answers to life, the universe and everything" (Winchester, UK: Iff Books, 2014) 27 - 30.
That’s all the prep we need. Let me just add that the current estimate for the number of neurons in a human brain is roughly one hundred billion.
The Thought Experiment
Take a few deep breaths, clear your thoughts, relax...
Imagine a telephone switchboard operator circa 1945:
She is connecting many incoming electronic signals (phone calls) by physically connecting wires that run between telephones or sub-stations, in a fashion not too remotely dissimilar from the neurons in your head.
Of course neurons can’t think, so if she confuses you, replace the human operator with the racks of mechanical relays that performed the same function starting in the 1950s.
Now imagine those phone calls coming in and our operator spending her day plugging and unplugging wires or if you prefer, a relay clicking open or closed as it makes or breaks an electro-mechanical connection between two wires in the international network of the telephone system.
The result of each unit of activity, is pretty straightforward right? There is simply the making or an unmaking of an electrical connection, eventually resulting in a mundane and expected physical activity; a phone call being completed or disconnected.
Now pan back and visualize two relays, then four, then a whole room full of them. There are still just a bunch of simple mechanical actions going on, electrical connections being made, and phone calls being completed. Now try to imagine racks and racks of telephone relays as far as the eye can see, all doing their electro-mechanical thing. Imagine yourself rising into the air until you see relays receding to the horizon in all directions. Imagine you are looking down at one hundred billion of them. Try to imagine all that electro-mechanical switching. Wow what a racket!
So, what would you expect the outcome of all that activity to be? A whole lot of phone calls that’s for sure. How about this, how about YOU! There you are in all your self-aware and not so self-aware glory. You have emerged from all this electro-mechanical activity. Maybe at this very moment you are feeling a complex rush of excited emotions because someone you have recently fallen in love with has unexpectedly entered the room. Can you envision how the qualities of that experience, your awareness of them, your very self, might come from the activity of all those relays? No? Now replace the relays with neurons as described above, making electro-chemical rather than electro-mechanical connections. Can you envision a giant network of them going off in all directions, as far as the eye can see? Now ask yourself the same question, one or one hundred billion, can you envision yourself somehow being the bonus result of all those squirting chemicals and electrical signals being passed around? Does the question even make any sense to you?
What could possibly be happening as we add neurons, so that somewhere between one and one hundred billion, full blown, self-aware, human consciousness, spontaneously emerges, even though there is no change in what each neuron physically does either alone or in-network?
That is the "hard problem of consciousness." That is the impossible gap that materialist scientists and philosophers must fill, in order to explain how your brain and you can be the same thing. I urge you to remember this the next time you read about the latest experiment purporting to show how scientists are "unraveling the mystery of consciousness" or other such public relations hyperbole.
You are probably thinking that this exercise is some kind of trick, that I have purposely left something out, or exaggerated or underplayed some critical element of brain operation or crucial detail of what the various materialist positions are.
Copyright © 2014 by Robert H. Clark. Published with permission.