I caught the Radio 4 program “The Infinite Monkey Cage” on my way back from work today, discussing the various theories that we are living in a simulation created by an advanced civilisation. This is something famously supported by Elon Musk, among others.
During the discussion, the common sense objection to this was well put by one of the guests. We have no reason to believe that consciousness can be simulated by a computer of any type. An example used was that we can simulate a storm in a computer, but the computer never gets wet. In other words we can believe that a computer could simulate consciousness that could pass the Turing test, but why should we believe that a computer could ever create something that was actually self aware ?
Then the argument was put forward that we know the brain is a physical object, so it must be possible to create something that functions as the brain does. The proposal being that if you replaced each neuron with a chip that had the same function, one by one, eventually you could replace the whole brain without the person changing. This is a common assumption that is made by reductionist materialists. Because we have shown that specific areas of the brain play a key role in basic functions that are seen as aspects of our self awareness (through types of brain damage for example), it therefore follows that self awareness is nothing other than a product of the physical brain.
I won’t deny that this is a logical assumption. Its one I made when I became an atheist. However it must be clear that this is an assumption. Its no less of an assumption than that lightning and thunder are signs that the gods are displeased. There is still a logic to it – humans aren’t able to create such awesome signs, so it must be the gods. If humans made that kind of a racket it would be because they were not happy about something. Its perfectly logical – it just has some mistaken assumptions because of ignorance about the nature of lightning and thunder,
I would argue the same about consciousness. In fact I would probably go further and say that we don’t even know what life itself is. The scientific definition of life is based on things that living organisms do, although even that gets a bit mixed up when you look at the likes of viruses (with undeniably good reason).
So how should this be addressed ? Its not reasonable to expect science to invent all kinds of ghosts and goblins to fill every possible gap where they could be hidden. That would be stupid – and contrary to the very valuable scientific process. But there are some fundamental issues where we must admit that our scientific knowledge and understanding is at best a rough pencil sketch of a guess. For all these areas, science can only be agnostic. To state that consciousness is purely a product of matter is to state a materialist belief, not a scientific fact,
The same cannot be said about Evolution theory, or a several billion year old earth. These are scientific facts.