(Rodrigo Peñaloza, Jan. 2016)

If you read this, beware that I want to take you through some mental experiments that will hopefully make you think about who you really are. These experiments were raised by Bernard Williams (“Problems of the Self”, 1973) and once again by Robert Nozick a few years later (“Philosophical Explanations”, 1981). It is about the philosophical problem of Identity.

Consider two persons, A and B, at some time t¹. Person A’s body is called A-body. Similarly, B-body is B’s body. Person A has memories, values, knowledge, modes of behavior, character traits, everything that amounts to his or her mental history up to time t¹, either conscious or unconscious. Call all this the A-material. Define similarly B-material. There is a machine called Switcher or just S. Upon entering S at a time t² > t¹, if that indeed happens, persons A and B switch bodies, so that afterwards, at time t³ > t², A-material is attached to B-body and vice-versa.

STORY 1. Now assume you are person A and you are told in advance, at time t¹, that something physically very painful (say, pain P) will happen to your A-body at time t³. You have to decide, solely on selfish grounds (forget about compassion or anything that might bound your decision to the very existence of B, this is only a mental experiment after all), whether you will enter machine S and switch bodies with person B at time t². What would you do?

STORY 2. You are person A and you are told in advance, at time t¹, that you will undergo the terrible pain P, at time t³, but before that, at time t², you will lose your A-material and your inner self will become B-material in your A-body, upon entering machine S. How would you feel?

Suppose that, in story 1, you decided to switch bodies. This means that you will be in B-body, so all the pain P can happen to A-body and you will not suffer. If you think that way, then it is because you think that you are your A-material, not your A-body. However, your situation in story 2 does not differ from your situation in story 1. Besides, story 2 is certainly much more frightening! You will not only suffer terrible pain, you will also lose all your mental history to become, in the end, another person, one that will undergo pain P. Indeed, in story 2, it is the B-material who will undergo pain P in your A-body, because your decision to story 1 tells me that you are not B-material. If you gave up on your A-body in story 1 in favor of your A-material and in disregard of B-material, how come now, in story 2, you are terribly frightened by the prospect of undergoing pain P from the perspective of B-material?

Now assume you decided not to switch bodies in story 1. Then you will accept to undergo pain P with your A-body and from the perspective of your inner self A-material. What does it imply to your situation in story 2? It doesn’t change anything. In story 2, you will still lose your mental history only to acquire another person’s mental history and suffer physical pain. You still will find story 2 more frightening, because it adds to the pain P in story 1 the fact that you will also lose all your mental history. Therefore, your choice in story 1 was illusory. Story 2 shows that your identity is neither given by your body nor by your mental history.

When Williams and Nozick raised these experiments, they wanted to show us that the problem of identity is paradoxical. Who are you? Is your body really necessary to the understanding of your identity? Worse, is your mental history really necessary too? If you stick with the presuposition that your identity is given by your body and your mental history, then it seems you are neither of them. Otherwise, the prospects in both stories wouldn’t matter to you. If they do, then you are wrong about who you are.

I would say this in another way: you are wrong about the way you ask who you are. Therefore, the problem is not the answer to your quest of self-knowledge. The problem is in the way you formulate your question in the first place, that is, it is not the path, but the “way you walk”. To symbolize this post, I chose Bee Gee’s “Staying alive” (listen here). Sleep well, if you can…

Like what you read? Give Rodrigo Peñaloza a round of applause.

From a quick cheer to a standing ovation, clap to show how much you enjoyed this story.