Beyond the Paradox of Personal Identity
Saying ‘I love you’ is a dangerous trap. Think about it, do you even really understand who or what you are referring to with the words ‘I’ and ‘you’? It doesn’t feel complicated, until you are confronted with the moral consequences of your statement. You thought you just expressed the feelings you were experiencing at the moment, only to find out at a later moment you made an implicit promise to love someone forever. If you stop, you can’t blame the person holding you responsible for lying, because technically they are right. You see, if ‘you’ refers to a person, and a person is an object extended over time, you told them that you (also a person and thus an object extended over time) are loving them now and as long as they exist and you exist.
Before you decide to never again tell others about your feelings, consider another practical problem there seems to be with the notion of identity. It appears to be really important to know who you are these days. It shouldn’t be surprising how many young people are dealing with an identity crisis, if you realise that we (as persons) have so many different and ever-changing aspects, that can even conflict between themselves. Just take a moment to reflect on the differences between how you see yourself and how others see you based on your appearance and behaviour. Even just looking in the mirror can emphasize the inconsistencies between your inner (mental) and outer (bodily) experience of identity. How are you ever going to feel ‘whole and complete’ with this underlying tension you feel in everyday life?
Now that we are aware of these problems with personal identity and their serious implications on our social interactions and our mental wellbeing, it would be nice to know how we could resolve these issues. In this paper we are going to do just that, by finding an answer to the following question: is there really something out there that corresponds with our idea of personal identity and if not, how to function without? I will start by laying out the fundamental principle on which our understanding of identity is build. Then I will discuss some different positions on personal identity in the history of philosophy: starting with the concept that personal identity is material (or somehow connected to our body) and continuing to the view that identity is a mere illusion. Finally, I will introduce a new perspective on personal identity, focusing on the causal connection between different versions of our material selves. This perspective can help us tackle the issues described above.
The fundamental principle on which our understanding of identity is build
If you search the internet for the etymology of ‘identity’, you will find that it comes from the Latin word ‘identitas’ which literally means sameness. For something to be the same can mean two things. In philosophy this distinction is maintained with the use of the terms qualitative and numerical identity. When x is qualitative the same to y, it means they both share similar properties. If x is numerically the same to y, it means both x and y refer to one object.[1]
Imagine arriving at a party and seeing the host wearing the same dress as you. When you greet each other, you may remark something about this awkward situation of qualitative sameness. Now, if at one point later in the evening (and a few drinks) someone exclaims you two are wearing the same dress numerically speaking, that should be a whole lot more awkward. Meaning you somehow ended up together in the same dress. Good gracious, I wouldn’t want to miss that party!
When we speak of a person being the same person, we compare this person with themself, only at another point in time. So now we are speaking of identity over time. Funny thing is, things change (qualitative), but remain the same (numerical). The same dress is at one time clean, another time stained with beer. Do you already see the paradox: how can something be both identical and different from one time to another?[2] Hence the foundation of personal identity is a paradoxical one: the idea that there is something persistent through time, while that something is also changing in material properties.
To understand why we use such an impossible concept like personal identity, we only have to look at the seemingly simple interactions we have with others and ourselves in everyday life. We want to think that the friend we are drinking tea with, is the same person we grew up with doing silly things together. We want the person we married, to hold their promise and never leave us. We want that man who murdered the little girl to be held responsible and be sent to prison for many, many years. We want to look back at pictures and be able to say, that is me performing or winning at that volleyball competition. All these things, coming down to moral responsibility, seem to be impossible without the idea of a persistent identity.
Different positions on personal identity in the history of philosophy
Thomas Hobbes
Of course, I’m not the first one to question our notion of personal identity. A common assumption is that it is the existence of our body that gives us persistence through time, even though all our cells replace themselves eventually. There is an ancient Greek story that represents this idea. It’s the story of Theseus, a hero who battled many enemies with his ship. Obviously, his ship needed to be repaired from time to time. So, the thinking follows: if after a while all parts of the ship are replaced, we would still see it as the same ship, numerically. So intuitively we are inclined to attribute identity not to the exact material parts or atoms of a thing, but to a form that holds the matter together.
Thomas Hobbes, a philosopher living in the 17 century saw a problem with this thinking. The Enlightenment was in full sway and many philosophers were breaking with the scholastic tradition based on Aristotelian ideas. Hobbes proposed a new thought experiment regarding the ship of Theseus: “if some man had kept the old planks as they were taken out, and by afterwards putting them together in the same order, had again made a ship of them, this without doubt, had also been the same numerical ship with that which was in the beginning; and so there would have been two ships numerically the same, which is absurd.”[3] To rephrase it, what Hobbes is pointing out is that we can’t accept the idea of personal identity as sameness of matter (persistence) and the idea of personal identity as sameness of form (change). If we do, it will lead to absurd consequences like that two distinct objects in time and space are also the same object.
Hobbes’ solution to this problem is that the alternatives posed above should not be viewed as exclusive competitors. Identity can exist on all those ‘layers’, matter and form. Each layer has a partial answer, correct if limited to its own domain, but inadequate when generalized.[4] For persons the most used domain would be form or motion, as Hobbes describes here: “if the name be given for such form as is the beginning of motion, then as long as that motion remains, it will be the same individual thing; as that man will always be the same, whose actions and thoughts all proceed from the same beginning of motion.”[5] Thus, our sameness lies in the uninterrupted motion of our everchanging matter. Therefore, as long as the motion remains we are the same person, whose actions now, can be held responsible later.
Like every other, Hobbes was a child of his time. Even though he tried to overstep the Aristotelian tradition, he still used Aristotles’ hylomorphic terms: matter and form. Which is tricky, because form is a postulated entity that we can’t point out in the world. And even though his redefinition of personal identity seems to bypass the paradox, it doesn’t really help us with the practical problems we have in daily life because of the underlying tension.
David Hume
Another attempt to resolve the tension of the paradox of personal identity was made a century later. It was David Hume, who argued to abandon the whole idea that there is something persistent in us. Check it out for yourself by repeating his experiment: “For my part, when I enter most intimately into what I call myself, I always stumble on some particular perception or other, of heat or cold, light or shade, love or hatred, pain or pleasure. I never can catch myself at any time without a perception, and never can observe anything but the perception.”[6] He says we are never aware of any constant invariable impression from which we derive the feeling of having an identity. We “are nothing but a bundle or collection of different perceptions.”[7] What we experience, rather, is a continuous flow of perceptions that replace one another in rapid succession.
To Hume there is no paradox, only an experienced confusion of two different ideas. The first being the idea of sameness or identity, what Hume defines as “an object, that remains invariable and uninterrupted thro’ a suppos’d variation of time”.[8] And the idea of diversity, what Hume defines as: “several different objects existing in succession”.[9] Though these two ideas of sameness and related objects are perfectly distinct, we combine them unwittingly in our daily thinking. Hume explains why we do that: “That action of the imagination, by which we consider the uninterrupted and invariable object, and that by which we reflect on the succession of related objects, are almost the same to the feeling.”[10]
How does this happen? When we look inside ourselves and become aware of the smooth transition of all the different perceptions, rapidly following each other up, we tend to see this motion as one continued object. It happens so fast that when we become aware of this mistake it is easier to yield to it and come up with a solution for the uncomfortable feeling of contradiction, than to correct the mistake. Hume describes how we do it: “In order to justify to ourselves this absurdity, we often feign some new and unintelligible principle, that connects the objects together, and prevents their interruption or variation.”[11] In other words, our imagination creates something unknown that connects the parts beside their relation. That mysterious something is what we call personal identity.
So according to Hume the answer to our research question would be: no, there is nothing out there that corresponds to our notion of personal identity, only in our imagination. Well, in that case we don’t have to worry anymore about knowing who you are, because there is nothing to know, only different perceptions to observe. Only problem remaining would be that of moral responsibility. Not having a persistent core would mean that your boss can suddenly decide to pay you less, because he has different perceptions today than the day you two made an agreement. That doesn’t seem as a completely satisfactory solution.
Version Identity
Another way to look at personal identity would be through the lens of different versions of the same person, linked together by causality. I see myself as a completely different Tanja than I once was, but I still can remember the previous Tanja and her experiences and I am conscious of the influence those experiences have on me to this day. This version of me could not exist without all the previous versions. If we would translate it to Hume’s words: the versions are the related objects and the relation between them is causality. Maybe we could even say that what Hobbes described as motion, could be the whole causal chain of all our versions. We don’t need a form or any other imaginary placeholder for our versions.
In our conversations we refer to versions all the time. If I say: my paper is almost finished, I refer to the most recent version of it on my computer, not the first draft or the finished one in the future. Or if I complain about my computer that it is slow, I refer to the version of my computer that has not been restarted or updated for days while working on this paper, not the one I bought three years ago. The same goes for people, when we talk about a person, we actually refer to the most recent version of this person (a real material object at a specific time, with all the past versions causally connected to it). ‘I love you’ becomes: I, the most recent version of me, loves you, the most recent version of you.
But what about moral responsibility? Let’s do a little thought experiment from the perspective of version identity. Let’s say I want to see my friend Manon and I call her to make an appointment. She agrees to see me the next Wednesday. When I meet another friend and tell her I made an appointment with Manon, I’m referring to the most recent version of Manon that I remember: the one who was on the phone, not the one I will be seeing in the future. In the meantime, Manon has changed a little bit and is a few versions newer, but most likely the new version of her still remembers our appointment. It is also likely this version of Manon has similar values and interests as the previous version, so I can assume safely she will show up to meet me.
It would be another story if, for example, I would volunteer to help homeless people and take an oath to do this for at least three years, because that version of me believes that helping them is the purpose of my life. In the course of the following two years different experiences shape newer versions of me, with the most recent one without the belief helping homeless people is the most important thing in my life. Could this new version of me be held responsible for breaking an oath made by another version of Tanja with different believes? That would be irrational. The same goes for crimes made by versions of people who are gone since and exist now as versions who would not do such things because of different values and believes. Clearly this perspective on personal identity is not what the moral system in our society is set up for today. It should be though and it could in the future, if we would take the expired and paradoxical definition of identity seriously and replace it with something more in tune with reality.
Conclusion
Now that we have reached the end of this paper, we can give an answer on the research question I proposed at the beginning: no, there seems to be nothing in the external world that would correspond with the traditional definition of personal identity. Let’s summarize how we got to this conclusion. First, we uncovered the principal behind personal identity: that we are something persistent over time (numerical sameness) while changing in properties. Next, we saw how Hobbes dealt with this puzzling contradiction. He proposed to see identity on different layers: as matter or as a postulated form that holds the changing matter together through time as a motion. Afterward we went on an adventure with Hume inside his mind, where we didn’t see any form or other thing holding his perceptions together besides the relations between these objects. He believed we mistakenly see the transition between those perceptions as an uninterrupted object and to deal with that mistake we make a second mistake by imagining something mysterious holding the perceptions, that we call our identity.
So, are we doomed to be lost, now that it seems we don’t have a persistent core over time? No, it appears to be a better idea to lose the whole concept of personal identity as sameness over time, accepting only the causal relationship between different versions of ourselves. We already refer to the most recent version of things all the time, why not do the same with people? In doing so there is no need for identity crises and in addition we can still honour our wish to hold each other responsible, insofar as the recent versions of us resemble the acting version. Thus, next time you feel the urge to tell how you feel about the wonderful person lying next to you, don’t hold back. Just be sure that person knows you are talking about them and yourself in terms of versions, a specific combination of matter at a specific moment in time.