Philosophy 101

Critical Thinking Exercise Option #5

Mind Uploading: A Cure for Death?

The question of whether machines can have consciousness is not new. Proponents of strong artificial intelligence argue that the appropriately programmed computer really is a conscious mind. In contrast, weak AI claims that machines do not have consciousness, mind and sentience but only simulate thought and understanding. Such a machine is often called a philosophical zombie– something that, from the outside, looks and sounds human, but on the inside lacks all phenomenal experience. But how are we to tell? We know about human consciousness only from our own first-person perspective, whereas artificial consciousness will only be accessible to us from the third-person perspective.

What does this mean with respect to the possibility of keeping our minds alive after the death of our organic bodies? “Eventually the mind will become migratable information, just like files can migrate from one device to another and live in the cloud,” says Michael Graziano, a professor of psychology and neuroscience at Princeton University. “When the information processor”—the brain— “goes, you’ll be able to copy [the mind] and implement it in other hardware.” Consider the following:

Uploading procedure circa 2110:

A woman 100 years from now walks into a hospital to undergo a mind uploading procedure. She is given general anesthesia and wheeled into a surgical suite where an open‐heart bypass surgery is performed hooking her vascular system up to a set of external pumps. These pumps first perfuse a chemical fixative, glutaraldehyde, through her vasculature so that it quickly reaches every cell in her body and in particular every neuron in her brain. This perfusion of a poisonous chemical fixative is done to crosslink the protein machinery within every cell, fixing these proteins in place and preventing decay. Next, another poisonous chemical fixative is perfused, this time osmium tetroxide, which fixes lipid molecules in place. These two steps (fixation of proteins and fixation of lipids) are crucial in that they use chemical bonding to “glue” all the molecular machinery within her cells together.

Next our patient’s brain and spinal cord is prepared to allow for nano‐resolution scanning. The first step in this process is to perfuse her vasculature with heavy metal staining solutions, like uranyl acetate, that bind to cell membranes allowing them to be later visualized under an electron microscope. Next all water must be removed from within and between the cells and replaced with a plastic resin that can be hardened to rigidify the tissue allowing it to be cut into smaller pieces and imaged. This is done by perfusing her first with ethanol to gradually leach out all water, then with an organic solvent to leach out the ethanol, and finally with increasing concentrations of plastic resin dissolved in the organic solvent until every region of intracellular and extracellular space is filled with pure plastic resin.

To assist in this process of removing and replacing water with plastic resin, several holes are drilled in our patient’s skull and tubes inserted through these to reach into the ventricular and subdural spaces of her brain. Normally, our brain and spinal cord float in a liquid called cerebrospinal fluid in a “sack” of tough material called the dura mater. The inserted tubes allow the ethanol, solvent, and plastic resin to be directly circulated within this dura mater sack while these solutions are simultaneously being perfused through the patient’s blood vessels. At the end of this process the patient’s brain and spinal cord are floating in pure plastic resin and every nook and cranny of intracellular and extracellular space is also filled with this plastic resin.

At this point our patient is wheeled into a 60o Celsius oven which hardens the plastic resin in her brain and spinal cord into a solid block. Skin, muscle, vertebra, and skull bones are removed revealing the dura mater sack. This tough material is then peeled back to reveal a perfectly preserved brain and spinal cord (including initial segments of cranial and spinal nerves) encased in an amber‐ colored transparent plastic sheath. Every neuron, every synapse, every delicate neuronal process in the woman’s central nervous system is now perfectly preserved down to the nanometer level – the most perfectly preserved fossil imaginable. Key molecular components like ion channel and receptor proteins are also preserved ‐ chemically fixed in position by the glutaraldehyde crosslinks and embedded in the plastic matrix.

The patient’s plastic embedded brain and spinal cord is then taken to an automated sectioning machine which uses incredibly sharp diamond knives to slice her brain into long strips just 100 microns thick, and these strips are collected on long spools of tape. A slight heating of the diamond knives is used to soften the plastic during this thick sectioning procedure, in this way no material is lost or damaged during this thick sectioning. The thousands of spools of tape, each containing many brain strips, are then loaded in parallel into thousands of electron microscope scanning machines. Each machine scans the surface of a strip with thousands of parallel electron beams, each just five nanometers wide, quickly producing a high‐resolution two-dimensional picture.

Then a focused ion beam is used to ablate away the just‐scanned top 5 nanometers of the strip, and the newly revealed surface is again imaged with the scanning electron beams. It takes 20,000 repeats of this ablation and imaging process to go through the entire 100-micron thick strip, but in the end a full three-dimensional map of the tissue is produced with 5x5x5nm resolution. Once all the brain strips have been imaged via this destructive process our patient’s original physical brain and spinal cord will have been destroyed, but a 5x5x5nm resolution volume image of her entire brain and spinal cord will have been acquired in the process.

This volume image is then processed in a computer to map out the connectivity of every neuron in her original brain, and to estimate the strength and type of each synaptic connection. This map of neuronal connectivity is then interpreted in light of the last 100 years of neuroscience knowledge (i.e. the years 2010 to 2110) to yield a map of the functional properties of all neurons and connections suitable for simulation in a computer. Recall that the plastic preservation procedure preserved the cranial and spinal nerves that connected the original biological brain with the body’s sense receptors and muscles.

Using these simulated nerve roots, the computer simulation is now “hooked up” to a robotic body –tying signals to and from the robot’s actuators and sensors, into the simulated brain’s cranial and spinal nerve roots. and sensors into the computer brain’s cranial and spinal nerve roots.

Using thousands of tiny motors, every human muscle has been duplicated within this robotic body. Precision lenses serve as eyes. Highly sensitive microphones allow audio sensitivity. A 100-terabyte hard drive has been installed (which is approximately the size of a dime), to collect and store all new experiences this “person” will have, from which the artificial brain can then draw.

The initial states of activity of neurons in her simulated brain are set to approximate waking up from a full shutdown surgical procedure like the PHCA procedure described above. Then the simulation is started up. Our patient groggily opens her new robotic eyes and cautiously stretches her new robotic arms into the air. It will take many weeks of practice for her to get fully used to controlling this robotic body and some tweaking of the simulation parameters before she is satisfied with her new sensory receptors, but she already knows the operation was a success as she practices recalling memories of her previous biological life. Once fully checked out, she heads home in her new robotic body to reunite with friends and family members many of which have also undergone a similar procedure.

Your assignment is to write a three-to-four-page paper (about 1000 words), which responds to these questions:

When “it” wakes up, it will act like her, and think that it is her, but will it “really” be her? Has she achieved immortality? Is this a procedure that you would be willing to undergo, assuming that it will work as described?

As you respond to these questions, be sure to reference at least two of the philosophers that you have been reading within Unit Seven: John Searle, David Chalmers, Keith Frankhis, and/or Thomas Nagel.

As before, your essay will not be evaluated on whether I agree with what you are saying. I will be looking at your understanding of the issues, but, mostly, I will be looking at the amount of depth, development, and thoughtfulness that you bring to your answers. I will also look to see that you develop arguments for your conclusions, and that you avoid dogma and unsupported opinion. To this end, avoid expressions such as “its true for me,” and, “I feel.” Provide thinking rather than feeling, and arguments rather than opinions.