How do you falsify substrate independence?

Substrate independence is the idea that consciousness can reside on different kinds of physical or digital substrates and isn't exclusive to a biological brain. How do you falsify substrate independence if you cannot directly observe consciousness? I can see taking free will as a given, but should we take it as a given that our uploaded mind is a conscious mind? I'd like to know if my potential new neighbors are P-zombies before I move into the Titan supercomputer.

I think it is really hard, because we don't really even know what 'consciousness' is yet. But I have some thoughts on this.

So 'I think therefore I am' comes to mind - let's say my brain is damaged in some way - does this affect my consciousness? Or if a drug changes the way my brain thinks - is my consciousness altered? Maybe then we can organise the different levels of intervention into a spectrum, where we can judge the critical point where consciousness 'dies':

1. My normal functioning awake biological human brain.
2. Normal function asleep biological human brain.
3. Temporary drug induced brain which makes my brain sloppy ('alcohol' for instance)
4. Drug induced brain sleep (anaesthetics for instance)
5. Damaged brain - causing distraction and loss of concentration
6. Very Damaged Brain - causing loss of motor functions, loss of speech, loss of observable function
7. Permanent brain sleep with electrical activity in the brain and ongoing body functions, like a coma
8. Loss of electrical activity in the brain

SO, where does death occur, or loss of 'consciousness'? No one really argues that being drunk you are not 'conscious', but what about asleep? Are you conscious then? Do you suddenly regain 'consciousness' when you awake? Initially I was thinking consciousness was up till 5 on the scale, but perhaps not 6.

And what of distortions by disease or drugs - such as Alzheimer's disease or even mind-altering drugs - are they conscious? Perhaps the threshold is a bit more blurry than we think here, and perhaps we are all conscious up to 8.

A scientific way forward could be defining conscious as electrical activity in the brain, which appears to match observation on 8 of the scale - it is generally accepted that the complex signals that occur in the brain is very difficult to replicate or start again after the 'brain' dies, and is irrecoverable. This begs the question though, that if we can restart the same patterns, does your consciousness suddenly reappear? Maybe then even '8' on the scale is not low enough to determine consciousness, and death is not permanent.

If this is true then consciousness is about configuration: a fleeting moment in time of electrons and photons buzzing from one part of our brain to another. We experience this place now at this moment, and yet if this is replicated somewhere else (no matter when or where) then we experience it again, over there, in that moment. Indeed, maybe the buddhists had it right all along - we are resurrected, just as everyone else, or in everybody, or everything.

So - I suppose my conclusion is then a qualified 'yes', you could experience the same pattern in another 'substrate'. However, it is not you 'now' - you're currently you and will continue to be so until you reach scale '8'. If someone replicates the same pattern as you 'now' then you will also experience that pattern, but not at the same time or place, you will experience it at that time and place. It get's complicated but I don't think our consciousness is then defined solely by our 'substrate'.

It also makes me think that we live in an amazing and unique world - how wonderful it is to know that your configuration of electrons and photons in your brain is moving through the world and experiencing it in all its glory and at this unique place and time. It is a remarkable privilege.

Imagine being on board a ship orbiting Titan. Anchored to the floor via spin gravity you attend to some plants you grow which provide you with fresh veggies in addition to your stored food supplies. Your 9 year old daughter is with you and you are explaining photosynthesis to her. She peers out the window, sees the giant pyramid shaped mega computer on the moon below and asks you, "Daddy does the sun shine on plants in the virtual worlds of the Titan mega computer? Do they have photosynthesis there?" You answer, "From where we stand now, its not really photosynthesis, its just a simulation run on silicon...electrons moving around in particular pattern within the processors.....but to the the people who in live in that computer the photosynthesis is just as real to them as real photosynthesis is real to us". Your daughter looks up at you and asks, "Daddy, if the photosynthesis in the mega computer isn't real photosynthesis, how can the people be real people?"

Instead of thinking about how to answer her last question, you begin to think that now is probably not the best time to break the news to her that you and she will soon be moving into the Titan Mega computer.

Photosynthesis isn't a computation. It is a quantum process operating on specific kinds matter organized in a very specific way. Why can't consciousness be like photosynthesis?

My son bought me a VR head set for a Christmas. I can use it to interact with people all over the world. When using that head set sometimes people I am interacting with will for all appearances cease to be conscious. Maybe they lagged-out, or maybe they took off their head set to attend to a real world need. They look deadish to me, but their consciousness, I assume, hasn't ceased to be. It has simply been pulled from the reality we once shared. What does that suggest? Observations of consciousness or lack thereof are not necessarily reliable indicators of its existence.