This is a series of thought experiments intended to challenge your assumptions about who you are. There are no right or wrong answers, these experiments only serve to expand your perceptions. If you take them in good faith, they may add a layer of complexity to how you see the world and yourself. 

Mary’s Room

Created by Frank Jackson, the Mary’s Room thought experiment examines the idea of qualia. In my retelling, I do away with the room. Mary is a brilliant neuroscientist, who knows everything there is to know about seeing color. For whatever reason, Mary has never seen color. Her world is black, white, and shades of gray. One day, Mary gets a red apple and she is able to see the apple’s color. For the first time in her life, she sees the color red.

Does she learn something new from seeing the color? To be clear, I am not asking if she has a new experience, I am asking if she gains new knowledge about the experience of seeing red. In other words, does experience provide a type of knowledge we cannot get from quantitative information alone? 

If you think she has gained new knowledge then you are acknowledging there is something intangible or nonphysical about us. There is some part of our experience that cannot be found in the brain. In this case, the self could be in part derived from the mind or the soul. 

Transporter

Derek Parfit’s Transporter Thought Experiment further tests our perceptions of qualia or the soul. We have a Transportation device. To use this device, a person steps into it on one side. The device scans the person while simultaneously obliterating them. At a different location, a corresponding device produces an exact copy of the person who was just obliterated. The copy has everything the original did: memories, genes, bladder contents, scars, everything.

Is the copy the same person? Or did we just kill someone?

Let’s say the copy comes up to you, shakes your hand, and introduces themselves. How would this affect your opinion? 

Do you think a manufactured copy of a person would look or act like the original? If the self comes from a soul, and a copy of a person does not have one, then presumably the soulless copy would not seem like a normal person.  

If you think there is some experiential knowledge (qualia) not found in the physical brain, as examined in the Mary’s Room experiment, would this new version lack knowledge the original had? 

If you think there would be no difference, then presumably you believe the sense of self originates from the material. Does the fact that the copy has been completely remade out of new material affect whether he is the same person or not? If you are not sure, check your intuitions by thinking about The Ship of Theseus. 

The Ship of Theseus

The paradox of The Ship of Theseus was found in Plutarch’s writings on The Life of Theseus. Imagine a you have a ship that is in need of repairs. In the course of repairing your ship you replace the mast, the sails, and the hull. However, you’re are not satisfied, you keep working until you have replaced every piece of the ship with new parts. By the end, the entire ship is new, down to the last nail. 

If the whole ship is made from new material, is it the same ship? 

If not, at what point did it become a new ship?

If yes, what makes it the same ship?

When thinking of the ship of Theseus in terms of ourselves, we are constantly changing; physically, our cells die and are replaced; psychologically, our memories are forgotten, rewritten, or replaced; socially, our roles change throughout our lives. If the Ship of Theseus becomes a new ship, then do we not become new people? 

If so, how much change is necessary to tip the scales from being our old selves, to being a new self? 

If you want to say that it is our consciousness or an overlap of evolving memories that allow us to maintain a continuous sense of self, then look at the Split Brain experiment. 

Split Brain

Like the Transportation experiment, the Split Brain was created by Derek Parfit. It was based on the real life scenario where, for medical reasons, people have their brains surgically split. Roger Sperry conducted several experiments with split brain patients. In these experiments, Sperry demonstrated that each hemisphere had its own independent stream of consciousness. The real life split-brain phenomenon is interesting enough, but the thought experiment takes it even further. 

Imagine that once the brain is split, each hemisphere is placed in a different body. Now, each body has its own stream of consciousness. 

Are there now two people? 

If yes, then are they the same person or did they become two distinct people? Can the soul split as well? 

If no, then is there still just one person? Which side of the brain is the real one? Or did we once again kill a person? 

Or maybe you think all of this is misguided, and the sense of self is no more than an illusion. In that case, it is perfectly reasonable to think that each body constitutes its own person. 

Chinese Room

Philosopher John Searle came up with the Chinese Room in 1980. Let’s say there is a man locked in a room. All he has for entertainment is a book of Chinese symbols and an instruction manual on how to use them (he does not know Chinese). One day, a piece of paper is slipped under his door. Looking at the paper, the man sees a series of Chinese symbols. Not sure what else to do, using his instruction manual, he writes corresponding symbols back. He has no idea what any of it means, but he slips the note back under his door. The next day the situation repeats itself, then again, and again. 

On the other side of the door is a Chinese woman who thinks she is having a conversation with the man in the room. To her, he is an intelligent and thoughtful Chinese man. 

While this thought experiment is intended to demonstrate the difference between AI and human intelligence, it also tells us a lot about how we understand the self. 

Does knowing that the man has no understanding of the messages and no intention behind his writing affect how you value the messages? 

If not, is that because the outcome or the consequence is the most important part? 

If yes, what elements (if any) are needed to give the messages value? 

If we thought of the man as merely a cog, or a piece of the machine, and the room as whole working to produce the messages, could the messages have value? 

If no, then does that mean we cannot get consciousness or a self from purely mechanical processes? Does that mean that we are more than a brain? 

Conclusion

Did these thought experiments challenge any of your beliefs or assumptions? After thinking about it in several different ways, how do you see your sense of self, has it changed? 

If you answered yes to any of these, we would love to hear from you. Please write to us at [email protected].