My daughter Sarah (who is planning to study theology) has insisted that I should explain here the idea of metempsychotic solipsism, something that came up when we were talking about something or other recently.
Basically, this is an improved version of reincarnation. There are various problems with the theory of reincarnation. Obviously people do not die and get born in perfect synchronisation, so it seems there has to be some kind of cosmic waiting room where unborn people wait for their next turn. Since the population of the world has radically increased over the last few centuries, there must have been a considerable number of people waiting – or some new people must come into existence to fill the gaps. If the population were to go down again, there would be millions of souls left waiting around, possibly for ever – unless souls can suddenly and silently vanish away from the cosmic waiting room. Perhaps you only get so many lives, or perhaps we’re all on some deeply depressing kind of promotion ladder, being incentivised, or possibly punished, by being given another life. It’s all a bit unsatisfactory.
Second, how does identity get preserved across reincarnations? You palpably don’t get the same body and by definition there’s no physical continuity. Although stories of reincarnation often focus on retained memories it would seem that for most people they are lost (after all you have to pass through the fetal stage again, which ought to serve as a pretty good mind wipe) and it’s not clear in any case that having a few memories makes you the same person who had them first. A lot of people point out that ongoing physical change and growth mean it’s arguable whether we are in the fullest sense the same person we were ten years ago.
Now, we can solve the waiting room problem if we simply allow reincarnating people to hop back and forth over time. If you can be reincarnated to a time before your death, then we can easily chain dozens of lives together without any kind of waiting room at all. There’s no problem about increasing or reducing the population: if we need a million people you can just go round a million times. In fact, we can run the whole system with a handful of people or… with only one person! Everybody who ever lived is just different incarnations of the same person! Me, in fact (also you).
What about the identity problem? Well, arguably, what we need to realise is that just as the body is not essential to identity (we can easily conceive of ourselves inhabiting a different body), neither are memories, or knowledge, or tastes, or intelligence, or any of these contingent properties. Instead, identity must reside in some simple ultimate id with no distinguishing characteristics. Since all instances of the id have exactly the same properties (none) it follows by a swoosh of Leibniz’s Law (don’t watch my hands too closely) that they are all the same id. So by a different route, we have arrived at the same conclusion – we’re all the same person! There’s only one of us after all.
The moral qualities of this theory are obvious: if we’re all the same person then we should all love and help each other out of pure selfishness. Of course we have to take on the chin the fact that at some time in the past, or worse, perhaps in the future, we have been or will be some pretty nasty people. We can take comfort from the fact that we’ve also been, or will be, all the best people who ever lived.
If you don’t like the idea, send your complaints to my daughter. After all, she wrote this – or she will.