Immotality and Resurrection of All

On Mind Uploading and Replicating / Resurrecting Everyone Who Ever Lived

(An excerpt from Michael Shermer’s 2018 book Heavens on Earth.)

The sums involved in achieving immortality through the duplication or resurrection scenarios are not to be underestimated. There are around 85 billion neurons in a human brain, each with about a thousand synaptic links, for a total of 100 trillion connections to be accurately preserved and replicated. This is a staggering level of complexity made all the more so by the additional glial cells in the brain, which provide support and insulation for neurons and can change the actions of firing neurons, so these cells better be preserved as well in any duplication or resurrection scenario, just in case. Estimates of the ratio of glial cells to neurons in a brain vary from 1:1 to 10:1. If you’re not a lightning calculator, that computes to a total brain cell count of somewhere between 170 billion and 850 billion. Then factor in the hundreds or thousands of synaptic connections between each of the 85 billion neurons, adding approximately 100 trillion synaptic connections total for each brain. That’s not all. There are around ten billion proteins per neuron, which effect how memories are stored, plus the countless extracellular molecules in between those tens of billions of brain cells.

These estimates are just for the brain and do not even include the rest of the nervous system outside of the skull—what neuroscientists call the “embodied brain” or the “extended mind” and which many philosophers of mind believe is necessary for normal cognition. So you might want to have this extended mind resurrected or uploaded along with your mind. After all, you are not just your internal thoughts and emotions disconnected from your body. Many of your thoughts and emotions are intimately entwined with how your body interacts with its environment, so any preserved connectome, to be fully operational as recreating the experience of what it is like to be a sentient being, would also need to be housed in a body. So we would need a warehouse of brainless clones or very sophisticated robots prepared to have these uploaded mind neural units installed. How many? Well, to avoid the charge of elitism, it’s only fair that everyone who ever lived be resurrected, so that means multiplying the staggering data package for one person by 108 billion.

Then there’s the relationship between memory and life history. Our memory is not like a videotape that can be played back on the viewing screen of our minds. When an event happens to us, a selective impression of it is made on the brain through the senses. As that sense impression wends its way through different neural networks, where it ends up depends on what type of memory it is. As a memory is processed and prepared for long-term storage we rehearse it and in the process it is changed. This editing process depends on previous memories, subsequent events and memories, and emotions. This process recurs trillions of times in the course of a lifetime, to the point where we have to wonder if we have memories of actual events, or memories of the memories of those events, or even memories of memories of memories…. What’s the “true” memory? There is no such thing. Our memories are the product of trillions of synaptic neuronal connections that are constantly being edited, redacted, reinforced, and extinguished, such that a resurrection of a human with memories intact will depend on when in the individual’s life history the replication or resurrection is implemented.

In his book The Physics of Immortality the physicist Frank Tipler calculates that an Omega Point computer in the far future will contain 10 to the power of 10 to the power of 123 bits (a 1 followed by 10¹²³ zeros), powerful enough, he says, to resurrect everyone who ever lived. That may be—it is a staggeringly large number—but is even an Omega Point computer powerful enough to reconstruct all of the historical contingencies and necessities in which a person lived, such as the weather, climate, geography, economic cycles, recessions and depressions, social trends, religious movements, wars, political revolutions, paradigm shifts, ideological revolutions, and the like, on top of duplicating our genome and connectome? It seems unlikely, but if so GOSH would also need to duplicate all of the individual conjunctures and interactions between that person and all other persons as they intersect with and influence each other in each of those lifetimes. Then multiply all that by the 108 billion people who ever lived or are currently living. Whatever the number, it would have to be even larger than the famed Googolplex (10 to the power of a googol, with a googol being 10¹⁰⁰, or 10¹⁰¹⁰⁰) from which Google and its Googleplex headquarters derived its name. Even a googol of googolplexes would not suffice. In essence, it would require the resurrection of the entire universe and its many billions of years of history. Inconceivable.