I’ve been reading a book I’ve been interested in for some time: “The Mind’s I: Fantasies and reflections on self and soul.” The subject is probably obvious from the title. Within its pages I came across an very thought provoking line of inquiry.

First, let’s consider the “conventional” view of consciousness. The idea is that we have all these brain neurons – tens of billions of them – connected to each other by their arms and legs (or more correctly dendrites and axons.) They send signals to one another and somehow, out of this mass of connecting wires, arrives consciousness. This is largely the premise of the book “Connectome” which I discussed on these very pages.

Let’s apply a thought experiment. Suppose you take a person’s brain and tease apart all the neurons from each other. You put each neuron in its own nutrient bath (to keep it alive) and you fix some kind of radio transmitter on each of its inputs and outputs (e.g. arms and legs.) Each neuron can now pass signals to all its fellows as it did before, only now it’s using these transmitters. (This is technically impossible but go with me on this.) Is it reasonable to conclude that this brain is still conscious? Maybe, though something seems off.

Let’s get even crazier. Let’s say we observe that a particular experience – eating a cheese sandwich – causes the neurons to fire in a very precise order (as it almost certainly would.) Then, instead of placing radio transmitters on each neuron, we place little pulse devices that can zap each neuron just like a brain signal. At this point we should be able to activate (in this brain) the experience of eating a cheese sandwich just by zapping the neurons in exactly the same order (and same speed) they would be zapped during a “real” sandwich eating experience. But would our brain – a bunch of neurons lying in separate chemical baths, not even connected to each other but receiving zaps from pulse devices – be conscious? It seems hard to believe it would. What is binding these neurons together?

I can think of several possible conclusions from all this.

1) Dualists and spiritualists are right: there is an immaterial soul. Something that takes all that neural processing and in some way interprets it as a conscious experience. Of course, this is just taking one mystery – how does the brain work? – and replacing it with another – how does the soul work? (You could exchange the word “soul” with “mind” and make the same point.)

2) There’s some missing part to the connectome theory – some strange property that emerges out of complex systems like the brain, or dark matter, or weird laws of quantum physics, who knows what. This sort of thing is what I believe the quantum consciousness movement advocates.

3) Separate strands of unconnected brain tissue CAN be conscious. Maybe all sorts of weird complex systems can. Maybe clouds are conscious! Computers! The universe!

4) This one is hard to really put into words but I like it. We are presuming the brain has to correlate to this thing we call consciousness but we have never really defined consciousness. Maybe we aren’t really conscious at all? Maybe it’s just some kind of illusion? (But don’t we need to be conscious to be fooled by an illusion? Like I said, this one is tricky.)