It is July 16, 2214. I am at Popham Beach in what I still think of as Maine. I am standing in the sand, watching the waves strike the shore. Sand pipers run in the surf, looking for their lunch. I have a two-hundred year old memory of another visit to this beach. In that memory, the water is cold on the skin and there is a mild ache in the left knee—a relic of a quadriceps tendon repair. Today, however, there is no ache—what serves as my knee is a biomechanical system and is free of all aches and pains. I can, if I wish, feel the cold by adjusting my sensors systems. I do so, and what was once merely data about temperature becomes a feeling in what I still call my mind. I downgrade my vision to that of an organic human, then tweak it so it perfectly matches the imperfect eyesight of the memory. I do the same for my hearing and turn off my other sensors until I am, as far as I can tell, merely human. I walk into the water, enjoying the feeling of the cold. My companion asks me if I have ever been here before. I pause and consider this question. I have a memory from a man who was here in 2014. But I do not know if I am him or if I am but a child of his memories. But, it is a lovely day—too lovely for metaphysics. I say “yes, long ago”, and wait patiently for the setting of the sun.
In science fiction one of the proposed methods of achieving a form of immortality is the downloading of memories from an old body to a new one. This, of course, rests on the rather critical assumption that a person is her memories.
Philosophers, as should hardly be surprising, have long considered whether or not a person is her memories. John Locke took the position that a person is her consciousness and, in a nice science fiction move, considered the possibility that memories could be transferred from one soul to another. While Locke’s view does get a bit confusing (he distinguishes between person, body, soul and consciousness while not being entirely clear about how memory relates to consciousness), he certainly seems to take the view that a person is her memory. As far back as a person’s memory goes, she goes—and this brings along with it moral accountability. Being a Christian, Locke was rather concerned about judgment day and needed a mechanism of personal identity that did not depend on the sameness of body. Being an empiricist, he also needed a clearly empirical basis. Memory contained within a soul seemed to take care of both concerns nicely.
Interestingly, Locke anticipates the science fiction idea of memory transfer—he considers the problem that arises if memory makes personal identity and memory could be transferred or copied. His solution is what many would regard as a cheat: he claims that God, in His goodness, would not allow that sort of thing to happen. However, he does discuss cases in which one (specifically Nestor) loses all memory and thus ceases to be the same person, though the same soul might be present.
So, if Locke is right about memory being the basis of personal identity and wrong about God not allowing the copying of memory, then if my memories were transferred to another conscious system to compose its consciousness, then it would be me. So, in my opening story, if the being standing on the beach in 2214 had my memory from 2014, then we would be the same person and I would be 248 years old.
David Hume, another British empiricist, presented an obvious intuition problem for Locke’s account: intuitively, people believe that they can extend their identity beyond their memory. That is, I do not suppose that it was not me just because I forgot something. Rather, I suppose that it was me and that I merely forgot. Hume took the view that memory is used to discover personal identity—and then he went a bit nuts and declared the matter to be all about grammar rather than philosophy.
Another stock problem with the memory account is that if memory can be copied, it can presumably be copied multiple times. The problem is that what serves as the basis of personal identity is supposed to be what makes me, me and distinct from everyone else. If what is supposed to provide my distinct identity can be duplicated, then it cannot be the basis of my distinct identity. Locke, as noted above, “solves” this problem by divine intervention. However, without this there seems to be no reason why my memory of Popham Beach from 2014 could not be copied many times if it could be copied once. As such, the entity on the beach in 2214 might just have a copy of my memory, just as it might have a copy of the files stored on the phone I was carrying that day. The companion mentioned in the short tale might also have those same memories—but they both cannot be me.
The entity on the beach might even have an actual memory from me—a literal piece of my brain. However, this might not make it the same person as me. To use an analogy, it might also have my watch or my finger bone from 2014, but this would not make it me.
Interestingly (or boringly) enough, the science fiction scenario really does not change the basic problems of identity over time. The problems are determining what makes me the person I am and what makes me distinct from all other things—be that a scenario involving the Mike from 2013 or the entity on the beach in 2214. For that entity on the beach to be me, it would need to possess whatever it is that made me the person I was in 2014 (and, hopefully, am now) and what distinguished that Mike from all other things—that is, my personness and my distinctness.
Since we obviously do not know what these things are (or if they even are at all), there is really no way to say whether that entity in 2214 could really be me. It is safe, I think, to claim that if it is a copy of something from my memories, then it is not me—at best, it would be a child of my memory. It would, as philosophers have long argued, have the same sort of connection to Mike 2014 that Mike 2014 had to Mike 2013. It is also worth considering that as Hume and Buddha have claimed, that there really is no self—so that entity on the beach in 2214 is not me, but neither am I.