Do I exist?

On the face of it this seems a particularly silly question to ask. After all if I didn’t exist then how can I possibly question my own existence? The answer is surely obvious.

Or not. I think that the question posed is actually two questions. They are: Do *I* exist and the rather different Do I *exist*… You see the difference in emphasis I hope.

Taking the first question of whether *I* exist revolves around the question of is there an *I* a unique thing that is me that exists throughout time. It could be argued that the *I* of my youth is not the *I* of today. My physical appearance has most certainly changed a great deal since I was, say, 5 years old. I imagine that just about every atom in my body is different today than it was way back then. So even on the atomic level I am not the same person. This goes the same for the structure of my brain. My brain today is vastly different from that of the child that I was. My brain structure is also linked in a very deep way to the ‘structure’ of my mind. I have experienced much and learnt much in the years since I was 5 so again the question must be raised: Am I the same *I* that I was decades ago? In many real senses the answer must be No. Yet in another very real sense it certainly feels like I am the same person I was so long ago.

For one thing I have memories going back into my childhood. Is the *I* then a collection of memories that have a link through time. Am *I* the product of those memories? Of course the problem with this line of reasoning is that memory is notoriously fallible. If I forget important parts of my life through injury or simple old age does that mean that I am no longer *I*? What about false memories or hypnotic states or drugs that can add false information into the mass that makes up what is regarded as the essential *I*? Where does that leave my identity?

It is arguable that what I think of as *I* is being created millisecond by millisecond by my brain but is essentially an illusion. Maybe in order to function the *I* has been created by evolution in the brain/mind in order that I can act as a purposeful agent. Maybe those early humans born without an essential *I* found it difficult or impossible to cope with the many conflicting demands of their environment and so perished before they could pass on their failings to future generations? Maybe the *I* is being generated by the mind as just a way of managing a complex brain system.

The second question is whether I *exist* or not. It is possible though not necessarily plausible that we live inside an advanced computer simulation and are just fairly complex pieces of computer code. If we were written in a sophisticated enough manner we would never be able to discover this. In a very real sense, if true, it would mean that our entire existence is a fraud and that, again in a very real sense, we did not actually ‘exist’ in the sense that we would have no real presence. Another possibility is that I might be a machine programmed to believe that I was a ‘real person’. There would be no way to verify this by thinking about it because my ‘thoughts’ would have been programmed either to be incapable to conceiving of such a possibility or to come to the conclusion that I was mistaken. I could attempt to damage my body physically in order to expose the fraud but I could have been manufactured in a sophisticated enough manner to appear to bleed (or feel pain) or simply ‘experience’ the sensations without any of them actually occurring. In other words there would be no way of independently verifying my ‘real’ existence.

So, if I cannot prove absolutely that I exist where does that leave me? I think that the only rational position is to assume that I exist until proven otherwise. My experiences, questionable though they are, seem to support my existence in both of the senses I’ve been discussing. There is also nothing to suggest that I don’t actually exist despite the sceptical arguments already outlined. So, for the moment at least, I shall carry on as if I do indeed exist – even if it’s for the entertainment of a player in a computer game or for scientific knowledge during a simulation. What else can I do?