On Mon, Aug 25, 2014 at 01:02:44PM +1200, LizR wrote: > On 25 August 2014 10:30, Russell Standish <[email protected]> wrote: > > > Attacks on anthropic reasoning will work better by choosing a > > reference class which is indisputably a subset of the reference class, > > such as all human beings, and then demonstrating a contradiction. I > > thought I had come up with such an example with my "Chinese paradox", > > but it turned out anthropic reasoning was rescued from that by the > > peculiar distribution of country population sizes that happens to hold > > in reality. AR has proved remakably resilient to empirical tests. > > > > The Chinese argument shows we shouldn't expect to be in the largest subset > of the reference class (at least if it isn't more than 50% of the class, I > suppose). Doesn't that also scupper the Doomsday argument, though? Given > the number of people who have lived (and assuming only people count as our > ref class) we have about 100 billion or so people (I believe?) of whom 6 > billion are alive. So how come we're born now, when we have a 94% chance of > being born earlier (assuming a population crash as per the DD argument). >
You have to include all the people who will live in the future, as well as all those who have lived in the past. With exponential growth rates (business-as-usual), more people rapidly end up living in the future as the time until doom increases. I did do such a calculation, and came up with a 50% figure for a population crash by 2100 CE. I was about to question to 100 billion people figure you quoted above. If you look at figure 5.2 of my book, you'll see that most people have lived since 1000 CE. But if you integrate the area under the curve by eye, and multiply by 0.04 per year (approximate pre-industrial birth rate), you get a figure of around 40 billion people as having lived since 1000 CE, so your 100 billion can't be too far off the mark. Cheers -- ---------------------------------------------------------------------------- Prof Russell Standish Phone 0425 253119 (mobile) Principal, High Performance Coders Visiting Professor of Mathematics [email protected] University of New South Wales http://www.hpcoders.com.au Latest project: The Amoeba's Secret (http://www.hpcoders.com.au/AmoebasSecret.html) ---------------------------------------------------------------------------- -- You received this message because you are subscribed to the Google Groups "Everything List" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To post to this group, send email to [email protected]. Visit this group at http://groups.google.com/group/everything-list. For more options, visit https://groups.google.com/d/optout.
