Ship of Theseus

2 May 2020

My mother used to say life is a question. Your purpose is to answer that question. She died when I was just fifteen, but not before six years of mental decline. She probably would have died sooner were it not for the fact that she was part of an early Edelberg experiment. Edelberg’s work saved countless lives, but my mother’s was not one of them. In dying, my mother gave me the question I needed to answer. Why?

Hanna Edelberg was a brilliant computer neuroscientist. In graduate school she focused on the computational modeling of vital brain functions. Two years after completing her doctorate she won the Nobel prize in medicine for her work on the restoration of brain function in head trauma patients. To this day, Edelberg implants are still the primary treatment for brain injuries, replacing brain regions with a small neural supercomputer.

Edelberg’s work founded the field of mind engines. Through her work, we could model not just brain regions, but an entire mind. After their success with trauma patients, they began to be used for the elderly. As parts of the brain failed, or dementia set in, an Edelberg engine could carry more of the load. Over time, the engine could compute everything.

Throughout the entire process, patients claimed they felt no different. They still felt themselves, often better and more focused. Like a ship of Theseus, each board and nail of their mind had been replaced, but it was still the same mind. A mind of flickering carbon nanotubes rather than human flesh. It was more than a cure, it was immortality in our time.

But not for some.

A few of the early patients like my mother would gradually decline. Their Edelberg engines would start to glitch after a while, eventually failing altogether. In those that failed, younger patients would glitch sooner. Those at forty could last a decade, but those in their tweens would glitch within a year.

Only a tiny fraction would glitch. Perhaps one in 100,000. But it was enough to ban Edelberg engines for the young and healthy. It’s all well and good to be seventy and get a couple more decades, but seeking immortality at twenty only to die within a year was hardly do no harm.

As an undergrad I made Edelberg engines my research area. I focused on modeling algorithms. In my view the issue wasn’t hardware, but software. Since younger minds are still developing, perhaps it was a matter of software drift or an incomplete logic map.

The biggest challenge in my research stemmed from the fact that Edelberg engines couldn’t be copied. Their structure is formed by a quantum model built by parallel learning. Basically, patients had their brains switched to the engine a small bit at a time, and they learned to use it. As the engine learned, it gradually took over more of the load. Early patients had to undergo intense therapy sessions to regain function, but later the switch could be done dynamically, so the process was like waking up with a hangover ever few days for a couple months.

Because of the quantum nature, a mind couldn’t be copied. Technically, a mind could be copied by quantum teleportation, but that trick destroys the original. Even on a computer, each mind is unique.

My breakthrough came when I figured out how to make a duplicate of sorts. I developed a neural sensor that could split an engine pattern without breaking quantum entanglement. That way you could train a second engine while training the original.

For ethical reasons I could only duplicate small sections of a mind, but it was enough to analyze the structure. Through this, I found a way to determine which engines would fail, and which would not. The ones to fail were missing certain fluctuations seen in the patient’s organic brain. In a tiny fraction of people, the Edelberg engine didn’t make a perfect copy of their mind, and so over time it failed.

It became clear early on that the fluctuations weren’t random. They seemed to be part of the decision cascade. When we make a choice, it isn’t simply a single trigger of yes or no, do or don’t. There is an evolving pattern that strengthens or weakens a choice. There is no “I” that decides, but rather a “we” of neurons, as a kind of vote within the brain. The fluctuations were a part of that process. More specifically they were the swing voters of the choice. In each decision where the fluctuations appeared, they swung the decision in their favor.

It was as if the fluctuations were the embodiment of free will. Whenever a choice was made where the decision wasn’t clear, these extra fluctuations appeared to make the decision. And they only appeared in the brains of failing patients. In other patients the extra fluctuations never appeared.

You can see this in experiments. With neural stimulation you can hinder choice fluctuations, at least with simple choices like choosing one color over another. Apply the stim, and and a person is literally unable to decide. They can’t make a choice because the decision cascade can’t reach a critical point. But in those with the extra fluctuations, the cascade succeeds. The fluctuations should be hindered by the stim, but they aren’t. It is as if something outside the physical brain triggers the brain into making decisions.

For more than two decades I’ve studied these fluctuations. I’ve found that they appear in infants about a week after they are born, and they exist in the elderly to within an hour of their death. But the strangest thing is that the first and last patterns are consistent among people. The first signal of an infant is a decision to gather information about the body. The kind of thing you might do after an accident or injury. Am I okay? Is anything broken? A system check, if you will. The last fluctuations of a dying patient are harder to interpret, but the best evidence points to a shutdown instruction. Calm the brain, stop the heart. Time to die.

The fluctuations say hello to a new body, goodbye to an old, and trigger every important decision in a person’s life. They cannot be blocked by neural stims, and they cannot be copied. They are the faint evidence of a human soul.

I know this now. I know now my mother died not because of cruel fate, but because she had a soul. I should find comfort in this, but I don’t. Instead I am troubled by a new question.

How do I tell the world that some have souls, but most do not?