An investigation of the nature of personal identity requires that we first be clear on the concept of a 'person' which is involved, and secondly on the relevant sense of identity. John Locke, in his An Essay Concerning Human Understanding
, Book II, Chapter 27, is helpful on both. As far as the nature of a person is concerned he writes:
To consider wherein personal identity consists we must consider what person stands for; which I think is a thinking intelligent being, that has reason and reflection, and can consider itself as itself, the same thinking thing, in different times and places.
No doubt there can be borderline and controversial cases involving the effects of ageing and mental infirmity. But I shall accept Locke's account as offering a reasonable statement of the nature of a person. But if we are to move from the concept of person in general to the identity of specific persons, we must examine the idea of identity, for 'identity' can mean different things in different contexts. What is it to be the identical same person as you have always been?
We might say to a friend: 'I was impressed with your praise for your new electric bike so I have ordered the identical model'. That certainly illustrates a common use of the idea of identity but won't take us nearer the idea of personal identity. The bikes were of the same type but they were different bikes. Personal identity is my identity, and not just the same type of identity as that of my neighbour.
Consider a different context in which we might use the idea of identity. Suppose you and your companion are sitting enjoying the sun and some heavy drops of rain land on you. You both look up at the darkening sky, and your companion says: 'Are you thinking what I'm thinking?' and you both head rapidly for shelter. In other words, it is reasonable to say that you have both had the same or very similar thoughts. This is a reasonable use of the idea of sameness or identity, but it is referring to a qualitative identity, or to similarity, rather than identity strictly so-called.
Consider yet another context where we might speak of identity. Returning to the bed-sit where you lived as a student, you might look at the desk and wonder: Is this the same desk? If the owner says: 'The one you worked at long ago got woodworm but we found another one which is the very same'. You might think: 'Yes, that desk looks the same as the one I sat at but it's not my desk'. In other words, the idea of temporal continuity is what you were hoping for if the desk is to be your desk.
These three types of context in which we might speak of identity have suggested different facets of the concept, and all three are involved in distinctively personal identity: the identity must be uniquely mine; it must reflect the qualitative nature, the distinctive flavour, of my identity; it must have a recognisable temporal continuity.
There is a further important point much stressed by Locke. Locke distinguishes between personal identity strictly so-called, and bodily identity. He writes: 'As far as consciousness can be extended backwards to any past action, so far reaches the identity of the person; it is the same self now as it was then'. He is not interested in whether the body in its present state is composed of the same material particles, far less that it looks the same, as it did in the past. The 'I' has continued although the body has decayed a little. This implies a necessary connection between personal identity and memory. I discussed memory in last week's essay
so forgive me if I recapitulate a few of the points.
I distinguished between three types of memory, or three contexts in which we naturally speak of our memories. These contexts were our memory of how to do certain things – skill memory; of what we have learned or been taught – fact memory; and of what has happened to us in particular – event memory. It is the latter which is particularly relevant to our personal identity. How relevant?
I agree with Locke that memory is a necessary condition of our identity as persons, but that there are other factors which also contribute to our personal identity. Another important factor emerges when we note that the term 'person' is derived from the Latin persona
, which was originally a mask through which came the sound of an actor's voice. The term was then extended to mean a role in drama, or dramatis persona
, and from there it easily comes to mean a social role.
This extension took one form in Roman law, where the role in question was that of 'citizen', or bearer of the rights and duties of Roman law. In other words, in Roman law, the term 'person' is not the same as the biological notion of a human being but is an institutional notion. Locke stresses this aspect of being a person. He thinks of 'person' as a forensic idea; my identity as a person merges with my responsibility as a person. This suggests a second element in personal identity: I must accept responsibility for what I do because what I do expresses who I am.
But the origin of the idea of 'person' – a human being acting out assorted roles – has led to developments in many directions. Consider, for example, the assorted roles we play in everyday life. This extension was recognised by Shakespeare in As You Like It
All the world's a stage,
And all the men and women merely players:
They have their exits and their entrances;
And one man in his time plays many parts.
These parts involve, for example, the occupational role, or how we act when doing our job and how we interact with colleagues. This might be quite different from how we are with family, and different again with old friends; the strict boss can also be the indulgent parent and the pub crony. All this suggests that personal identity is more than personal memory, and that the assorted roles we have in everyday life are prominent in our personal identity.
In some cases, the occupational role dominates personal identity. There is said to be a tombstone which says: Here lies Hamish McTavish who was born a man and died a grocer. I don't know if this happens to grocers but it certainly happens to many doctors, professional soldiers and musicians. The demands, skills and duties of the job colonises the personalities and constitutes a major part of personal identity.
To suggest that memory and our assorted responsibilities and roles constitute essential components in our identity as persons is to follow Locke in distinguishing our identity as persons from our bodily identity. We are accustomed to thinking of identity in terms of the identity of a thing – the desk for which I have a sentimental attachment – but (as I argued at the start) there are other ways of looking at identity. For example, a good novel has a narrative identity, and a play has the identity of its dramatic continuity: As You Like It
has its own type of identity and a different one from Hamlet
, but neither is a thing, animate or inanimate.
As Locke suggests, our identities as persons differ from the identity of our bodies. Personal identity may be more like the identity of a novel or a play with their linked scenes and characters. That approach would give our personal identity a coherence and unity; it would link our memories, our responsibilities and our assorted roles.
Robin Downie is Emeritus Professor of Moral Philosophy at the University of Glasgow