It is easy to see oneself as the same person we were ten, twenty, or fifty years ago. We can define identity through our physical presence, life experiences, memories, and mental awareness of self. One can testify our persistence as a person through our existence as a person. But what makes us the same person? In this paper, I will argue for the “simple” view of the persistence of identity – that it is impossible to determine what single thing that makes us the same person over time.
I will support my claim with the refutation of the main complex view claims of the body, brain and psychological continuity criterion.
Entrenched in the “simple” view is the idea that personal identity, and the persistence of personal identity, cannot be measured through philosophical discourse or scientific investigation. There are a number of opposing arguments, known as complex theories of personal identity. In each of these arguments, the central claim is that either the body, the brain, or the psychological continuity of an individual determines how they persist as the same person (Garrett, 1998, p 52).
To call them complex is a misnomer – for each is far too narrow to properly define and explain personal identity.
Complex argument 1– Psychological continuity John Locke defines a person as a ‘thinking, intelligent being, that has reason and reflection and can consider itself as itself, the same thinking thing, in different times and places’ (Locke, 1689, p 1-6). This statement suggests that, in order to persist as the same person, we must have a mental consciousness which persists through time. We can say that a person is psychologically continuous if they have a mental state that is descendent from their previous mental states.
For example, this theory states that a five-year-old will be the same person when they are a 25-year-old, because their mental state in later years is descendent from their earlier years. Counter argument By its very nature, the idea of psychological continuity is flawed. It is not uncommon for an individual’s mental state to be changed so drastically that they could not truly be considered the same person. Several examples have been made by Waller: sufferers of cognitive impairments such as dementia, people who have gone through stressful or traumatic situations, and war eterans that are affected by post-traumatic stress disorder (Waller, 2011, p 198-210).
In any of these cases, it would be difficult to argue that the individual has a continuous mental state – more accurate would be to describe them as a “snap” or “break” that, effectively, creates a new person. The only conclusion is that these individuals do not persist, as their psychological states become radically different from their previous psychological states. Complex argument 2 – Persistence of the body Another expression of the complex view is the body criterion.
Put simply, a person is said to persist if they exist in the same physical body over time. In this case, the previously mentioned dementia or PTSD sufferers would be considered the same people, as their physical body has continued. The theory suggests a “brute physical relation” between body and identity (Korfmacher, 2006). Without regard for mental state, an individual is considered to have a persistent personal identity as long as their body survives. Counter argument This theory lends itself easily to thought experiments, and they quickly expose some problems.
If individual A receives an organ donation from individual B, can it be said that individual A has taken some of B’s identity? Surely not. It would be absurd to suggest that having the kidney or liver of another person would affect one’s persistence as an individual. Similarly, if individual C had their body cloned, it would not make their clone the same person. There is much more to personal identity than can be defined by something so comparatively insignificant as the physical body. Complex argument 3 – Persistence of the brain
The brain is the functional centre of the human body; the place where memories are stored, feelings are felt, and environmental signals are processed. It is unsurprising, therefore, that the brain is so often considered to be the “home” of personal identity. This theory is a staple of many science fiction texts – as a convention, the cognizant “brain in a jar” or brain transplant recipient is fairly common. Proponents of this “we are our brains” theory claim that, so long as the brain persists, so does the person. Counter argument
This theory seems to refer to consciousness rather than the physicality of the brain, so it is important to make a clarification between the two. Julian Baggini suggests that we should view the relationship between consciousness and identity similarly to the relationship between a musical score and the paper it is written on (Baggini, 2005, pp. 112-114). In other words, the brain is simply a storage space for our memories, thoughts, and self-awareness. Should it not, therefore, be so that an individual could simply persist as a brain in a jar, provided they could be sustained in that state?
If the entirety of personal identity is stored in the brain, there must be no need for the rest of the body beyond keeping the brain alive. Such a theory could not possibly be true – life experiences and interactions with the world are such an intrinsic part of identity that we could not persist without them. The theory that consciousness plays a significant role in the persistence of personal identity is appealing, but it can not be said that the brain alone could sustain consciousness.
Conclusion To call the simple view of the persistence of personal identity “simple” is almost deceptive; deep consideration on the subject quickly turns towards the complex. It is easy to grasp at the categories of body, brain, and mental state, but it would be wrong to say that the persistence of any of those equates to the persistence of an individual. Personal identity is something so much harder to define, and it is harder still to find definitive measures of its continuation. Personal identity is evasive, and fleeting; it is intangible, ever-changing. Its persistence is so much more than can be determined.