Ian asked:

I recently heard someone say, "I might easily have been someone else after all, mightn't I?" The
obvious question is, "Might he have been?" Any thoughts.

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First of all, we have to get clear what,

"(P) 'Individual x might have been individual y'"

means — as the truth of (P) is going to depend on what the context of utterance is. I'm going to
assume that (P) means,

"(P1) 'It is possible that x has different properties than x actually has.'"

Let 'x' refer to you. So what (P) means is that you might have had different properties. So, say, you
might have had the properties of being a professional footballer, whereas actually you are, say, a
professional basketball player.

In terms of possible worlds this turns out as:

"(P2) There exists a world w & At w, Ian exists and Ian is a professional footballer."

Well, you might say "look, that's all well and good but surely I can only exist in one world — whoever
that other "Ian" is, it certainly is not me!" What we need to then do is talk about counterparts of you. A
counterpart of you is an individual to whom you are similar too in some qualitative respect. Hence, P
turns out as,

"(P3) There exists a world w & at w, there exists a individual y & y is a professional footballer & y is a
counterpart of x."

(Remember 'x' refers to you.)

So, in answer to your question, yes you might have been someone else, but what that means is that
you have counterparts who are different from you. You might have been David Beckham but that is
only true if David Beckham is one of your counterparts.

I understand that all this is controversial, but anyanswer to this question is controversial — and I
think this is the best answer overall.I don't have time to go into details but see David Lewis, On the
Plurality of Worlds(1986) chapter 4, and John Divers, Possible Worlds(2002). Feel free to email me
with any questions.

Rich Woodward

What exactly is it to imagine that you might have been some other personfrom the person you
actually are? is it necessarily the same as imagining that you might have been differentfrom the way
you actually are?

Whenever we think about how different things might have been from the way they are, we are
thinking about other 'possible worlds'. No need to worry about how 'real' these possible worlds are
(Lewis takes the extreme view that other possible worlds are as realas the actual world). If you like,
it's just a convenient way of talking, nothing hangs on this so far as your question is concerned.

I am now thinking about another possible world. In this other possible world, I have just intercepted a
careless pass from an Arsenal player and I am racing with the ball towards the Arsenal goal. Other
information about me: my name is David Beckham, I play for Manchester United, I am married to
Victoria who used to be 'Posh Spice' from the Spice Girls. In my garage, I have a Bentley and a
Ferrari. So far, so good.

But now there come a tricky question. How did I get to be 'David Beckham', when my father's
surname was Klempner? Two possible answers to this: 1. In the other possible world I changed my
name (better name for an English footballer). 2. In the other possible world my parents were not my
actual parents but were in fact Mr and Mrs Beckham.

If I opt for 1. then I am not imagining that I might have beenDavid Beckham, I am only imagining that
I might have had the nameDavid Beckham (as well as various other enviable attributes). In that
world, one might suppose that there are twoDavid Beckham's, myself and the son of Mr and Mrs
Beckham (who hated sport and became an accountant).

So I opt for 2. How did my parents come to be Mr and Mrs Beckham instead of Mr and Mrs
Klempner? What the question is asking is what connects methe person writing these words at this
moment, to the person called 'David Beckham' in this other possible world. What makes this
individual (in Lewises language) mycounterpart?

This isn't a point necessarilyabout the first person. It makes sense to ask (although no-one ever
would) under what circumstances, and in what sense might George W. Bush 'have been' Saddam
Hussein, when the person asking the question is neither George W. Bush nor Saddam Hussein. I'll
leave you to work out the details.

To get back to Mr and Mrs Beckham. Let's say that in this other possible world, when the embryo
which later developed into me was just a few days old, it was secretly removed from my mother's
womb and placed in the womb of Mrs Beckham. Would that be enough to make me David Beckham?
All I am imagining now is my being substituted(!) for David Beckham. The embryo which would have
grown into David Beckham was either destroyed, or maybe became his non-identical twin brother
Derek...

Geoffrey Klempner