How Can We Know What Makes Us, Us?
Be warned. You will probably not remember much towards the end. Without further delay, let us begin. There are various schools of thought to explain what makes us, us. Intuitively, we’d like to think that an ongoing stream of psychological continuity is sufficient to constitute for personal identity. I am the same person as the boy before when some of his mental features such as his beliefs, memories and intentions survive as mine. Instead of a collection of disparate impressions, we think of memory as a continuity of our history that define us. X and Y are one and the same person at different points in time if and only if X has a psychological continuity relation to Y.
This explanation allows for the extension of consciousness from the past to the future, and it is through such a consciousness that X and Y is still the same person over time. Since the brain is responsible for the psychological qualities that define one’s personality identity. there will be psychological continuity if there is a transfer of brains. If X transfers his brain to Y, Y will be psychologically continuous with X. In this case, Y would be X.
But this means that it is possible for me to be psychologically continuous with two of me in the future at the same time.
It seems that such a view of personality identity has issues in accounting for numerical identity. Specifically, you cannot simply split into 2 identical selves. Let us consider this example. X decides to transfer the left half of his brain to Y and the right half of his brain to Z. So, Y possesses the left half of X’s brain, and Z possesses the right half of X’s brain. According to the psychological continuity viewpoint, both Y and Z are psychologically continuous with X. Hence, X is Y and X is also Z. However, X cannot be Y and Z at the same time as they’re not numerically identical to be one and the same. Psychological continuity perspective fails to meet the metaphysical requirements of personal identity in following the logic of a one-one identity relation.
When it comes to our personal identity, there is no room for duplication.
In response, if we’re arguing for psychological continuity, we can say that there is psychological continuity with only one person and no other being. This means that when a divide happens, as shown in the aforementioned case, X is neither Y nor Z. X dies. Y and Z are new identities in of themselves when both halves of X’s brain is transferred to them. But there is something alarming with this train of thought.
Who is who when X survives with half of his brain intact and the other half being implanted into Y?
Let’s switch our lenses and look at this from a different viewpoint. Let’s take up the perspective of physical brain continuity. It claims that we are our brains. It is crucial to point out that there is no need for the entirety of the brain to be present. The brain can be dissected, but it has a physical essence that cannot be exposed to dissection. If the physical essence is dissected, there will be no production of mental states and subjective experiences, leading to the end of psychological continuity. Thus, the fundamental physical essence of the brain that produces and sustains consciousness is also a necessary condition for personal identity over time. In this case, one ceases to exist in the progress of Alzheimer’s disease when the disease completely eradicates any bits of consciousness.
Sometimes I wonder — If you completely forget who you are and loses your personal identity, would it be immoral of your partner to leave you?
We can conclude that psychological continuity is required to account for personal identity. Imagine waking up next to your partner one day and he or she reacts in a totally radical manner, the least you would do is to suspect that your beloved one is acting out of character, especially when their memories, personality and beliefs are not progressively aligned to the past. What remains of us when we’re shorn of our pasts?
Are we left as the same people we were in infancy?
Unless you are able to explain how psychological continuity can exist solely as a soul element without the mental capacity of the brain, we can agree on the same tangent that psychological continuity is insufficient on its own. It is apparent that the brain, which is in charge of our psychophysiological processes, is absolutely indispensable. Whether the brain is a mere placeholder for consciousness or not, it is undeniable that the brain is necessary. If not, it will result in the loss of all objective, subjective and psychological experiences, which eventually leads to the loss of personal identity. But isn’t that life is all about? We all forget everything in the end, don’t we?
