Fans of science fiction are likely familiar with the continuity problem. You get beamed aboard the Enterprise by the transporter and everything seems to work perfectly. On Earth you are disassembled into your most fundamental particles in order to capture all of the information necessary to then recreate you in your exact state aboard the Enterprise.

The new you aboard the Enterprise is you in every detail, including your stream of consciousness – the thoughts you were having at the moment of beaming. But is it really you? Isn’t it more accurate to say that you were destroyed on Earth and are now dead, and a copy of you was created on board the ship? That is the continuity problem.

I have discussed this issues several times on this blog and on the SGU, including on this week’s show. The topic always provokes lively discussion. One common observation that I hear in response is that the continuity problem is not really a problem at all – we lose continuity every night when we sleep, and we are not worried about it when we wake up.

I have always found this analogy to be puzzling. It seems so transparently false, why is it so commonly used? When you sleep there is absolute continuity, it has no analogy to the transporter situation.

I think the confusion comes with the context of continuity. The sleep analogy is referring to continuity of stream of consciousness, or functional continuity. This type of continuity is broken all the time, including when we are in the deepest stages of sleep, for anyone who has general anesthesia, or for anyone who is unconscious from brain damage or dysfunction.

Continuity of consciousness, however, is irrelevant to the continuity problem, which refers to physical continuity of the brain.

The premise is that you are your brain. Your mind, consciousness, memories, personality – everything is your brain. Destroy your brain, and you are destroyed. Change your brain and you are changed.

When you sleep your brain is not destroyed. Physical continuity is maintained. Actually, functional continuity is also maintained, your brain simply enters into various different states of operation, which affects your waking conscious self as well.

A far better analogy for functional discontinuity is anesthesia, where your brain is literally turned off, to the point where there is not even any sense of the passage of time. Even still, there is physical continuity, and that’s all that matters.

Another point frequently made is that the new version of you aboard the ship would feel and think that it is you, and therefore it is. This is true in the sense that, to the new version it is absolutely you. It has your memories and thoughts and everything that is your consciousness. There is no problem from the perspective of the new you – it’s just not you. It’s a copy.

Transporters as envisioned on Star Trek will likely never be a reality. There are various non-trivial problems in terms of energy and information storage that make it impractical in the extreme. The continuity problem will likely be a real issue in another context, however – transporting ourselves into artificially intelligent computers.

Can we really upload our consciousness into a machine in order to achieve digital immortality? Would the new digital you be you or a copy?

I argue that it would be a copy, and physical continuity would be lost. This gets to another aspect of the continuity problem – are you the information that constitutes your consciousness or the physical substrate? I argue that you are both. Without your brain or the information it contains, you are lost, dead for all practical purposes.

If you copy the information in your brain and then recreate it digitally, or in any form, such as an analog physical artificial brain, the new creation may think that it’s you, but it is again just a copy. Your consciousness has not “moved” – it cannot move, because it is your brain, not just the information.

How, then, do we achieve true digital immortality? I can only conceive of one method. Our brains are actually two brains (the two hemispheres), each independently capable of consciousness. They are massively connected to each other, however, and work seamlessly together to form one whole brain and one consciousness.

I think this situation is analogous to having an artificial second brain, one that is capable of being independently conscious, massively interface with your biological brain. When first connected the artificial brain will be devoid of any memories, feelings, or personality. It may be devoid of all information, but I don’t think there’s a problem if it comes preloaded with factual information, such as new languages.

Imagine that this new artificial brain is designed to mirror your biological brain as it augments it. At first you may notice only greater memory capacity, but as the brain maps to your brain, processes information that you perceive, your thought and memories, it increasingly becomes part of the overall functioning of your unified biological-artificial hybrid brain.

Eventually the artificial brain will be capable of being independently conscious. You will notice this when your biological brain goes to sleep, especially when it is in the deep stages of sleep and not dreaming. Then your artificial brain is free to function on its own, and you will experience whatever it’s like to be just the artificial half of your brain. Perhaps it can independently control your body, and you can be awake and functioning even while half your brain sleeps.

If the artificial brain were powerful enough, eventually the biological portion of your brain may become redundant and an insignificant contribution to your overall unified consciousness. You may not even notice the difference when your biological brain sleeps – or if it dies. You will have become your artificial brain, with no loss of physical continuity at any step.

Some may say that you have changed, and this is a loss of continuity, but being changeless is not what is meant by physical continuity. We change ever day as we grow, age, learn, and experience. Changing is OK, as long as it’s an unbroken chain.

For me the bottom line is this – I would never step into a transporter. I would never allow my brain to be destroyed by any process that duplicated it in another form (computer, android, clone, etc.). I would, however, accept a neural implant that augmented my brain.

I do agree with the prediction that not only will we create artificial intelligence that is fully conscious, I think we will merge with it.