First of all, a few corrections. The estimate I have seen of the total number of homo sapiens who have lived is 60 billion, making today’s ratio closer to 10:1.

Secondly, it’s unlikely we can decrease that ratio significantly without colonising other planets. This may prove either impossible, or only possible in the remote future. Getting to that point means a stabilsation of the human population lest we run out of resources, or a drastic reduction in human population, throwing the ratio right out.

Thirdly, the Doomsday Argument (http://en.wikipedia.org/wiki/Doomsday_argument) suggests we might not last all that long – at least it’s unlikely we’ll last more than 10,000 years.

Finally, there’s a way to test this hypothesis: give yourself brain damage. It may be possible to simulate sensory stimulus, but unless you believe it’s possible to simulate thought itself (kind of like having a bot play the game for you – in which case, what’s the point of playing?), then our thoughts must be generated by the ‘real’ us. As such, the ‘matter’ in the game, such as our brains, are only part of the simulation and not doing the ‘actual’ thinking. So, if you severely injure yourself in the game in such a way to impair your thinking, and your thinking doesn’t change, then you have nice evidence to support the hypothesis that we’re in the game. However, if you injure yourself and your thinking is impaired, then that’s good evidence to suggest at least that our minds are not disembodied and detached from the apparent world.

A slightly less intrusive way to test this hypothesis would be to take mind altering drugs – not just perception altering drugs. However, it’s less reliable, as the effects could be simulated by automatic application of the same – or an analogous – drug on our ‘real’ brains.

And a final postscript – would it change the way you behave if it were true that we were in a simulation? I don’t think it should. It’s like Wittgenstein once said in a class: why did people once think the sun went around the earth? Because it looked like it did. Ah, but what would it look like if the earth went around the sun? So simulation or not, it doesn’t really change anything.

Paul