On this blog, we’ve recently tackled religion and the nature of existence, but we’ve left out one huge chewy topic that people tend to lump into this philosophical category, and that’s consciousness. You need only look at a site like Closer to Truth in order to see just how tightly coupled these ideas are in the public imagination. It’s also a topic of significance to me, as it was through writing on this subject that I first found myself exploring digital physics many years ago.
One of the great defenders of the specialness of human consciousness in the physical realm has been Roger Penrose, the man who proposed that consciousness was non-computable because it was founded on non-computable processes in nature. A lot of this blog has been about demolishing that idea. So on Penrose’s hypothesis, digital physics is pretty clear.
However, there are plenty of other ways you might integrate consciousness with discrete reality. For instance, take the essays submitted for the 2011 FQXI prize, on the subject ‘Is Reality Digital or Analog‘ (probably the highest profile public discussion forum on this subject in the last five years), and you’ll see the word consciousness showing up within the first four titles. What about these other models? Do they have anything to add? Here’s my answer:
Digital physics has nothing to do with consciousness, because consciousness has nothing to do with physics.
The notion that consciousness has any bearing on quantum mechanics, and therefore physics at large, is, to my mind, a lamentable side-effect of the times in which QM was first formulated. Poor old Neils Bohr had the unfortunate fate of hanging out with a bunch of logical positivists, who were sort of trendy at the time, and he tracked some of that muck back into physics along with him.
Enthusiasts on the topic of quantum consciousness point to the fact that observation of a QM event affects how it will play out. However, as we’ve seen in previous posts, we can generate identical effects in a simulation by simply asking the question–is information leaving the system or not? If it is, then an observation has taken place, if it isn’t, then an observation hasn’t happened yet.
In other words, particles are non-committal. They’ll hedge their bets and be everywhere until you force them to make up their mind. And forcing them to decide often has the side effect of forcing a bunch of their friends to decide too. In this regard, particles are rather like teenagers trying to decide where to go on a Friday night. They’re no more strange and magical than sixteen year-olds. (Though, admittedly, sixteen-year-olds are pretty strange.) Ask any self-respecting working particle physicist about the role of consciousness in QM, and they will struggle not to roll their eyes at you. This is why.
So if we can rule out consciousness having an impact on quantum mechanical events, and we can rule out its dependence on smooth symmetries of nature, is there anywhere left for the specialness of consciousness to hide? At this point, we invoke the principle of minimal complexity which we used to unpack the idea of god, and we ask ourselves if the universe is more or less complex if we have to carve out some special extra room for sentience in physical law. The answer, I’d argue, is that it’s more complex, and therefore massively unlikely. Nice though it might be to cogitate on, then, consciousness arises naturally out mechanistic physical processes, just like everything else.
But what about free will? Given that quantum mechanical events are completely unpredictable, isn’t there at least enough room left for that? Not in this model of the reality, there ain’t.
To describe the universe completely, we need to treat the rules that run nature and the data that they run on as a single closed system. Otherwise we haven’t finished describing them yet. Thus, if we find that a huge pile of random numbers are necessary for the universe to work, then they belong as part of our model–as a giant list of lottery tickets printed at the beginning of time and slowly spent.
Of course, a huge pile of random numbers that lasts for the length of the universe is a really, really awful implementation. The principle of minimal complexity strongly suggests that reality is better than that.
Free will, does it exist, then (at least in the sense of something special outside of logic)?
Sorry, no luck, as it were, so to speak, if you’ll pardon the pun, etc.