You can get anthropic-like effects without needing to vary populations (see for instance http://lesswrong.com/lw/3dy/solve_psykoshs_nonanthropic_problem/). So let’s see if we can do that with this example, and see if there really is anything different between royal siblings and nuclear war.
Start with 101 people, in dark rooms (you are one of them). These will be divided into two groups: one of 100 in the “no WW3” group, and a single person in the “WW3″ group. Then the experiment organisers get some of George IV’s parent’s DNA, and clone him a sibling if a coin comes heads. Everyone is (honestly) told the result of the coin flip.
This seems to have all the features of your example. Suppose you are told that there was no sibling clone. Then you can confidently say Probability(You exist [and know that George VI had exactly five siblings] | George VI had more than five siblings) = 0.
And yet the “anthropic” odds of being in the “WW3″ group remains 1:100. So something genuinely different is going on.
Whether you can apply the same reasoning to the anthropic cases is what is debated between SIA, SSA and my favourite ADT.
You can get anthropic-like effects without needing to vary populations (see for instance http://lesswrong.com/lw/3dy/solve_psykoshs_nonanthropic_problem/). So let’s see if we can do that with this example, and see if there really is anything different between royal siblings and nuclear war.
Start with 101 people, in dark rooms (you are one of them). These will be divided into two groups: one of 100 in the “no WW3” group, and a single person in the “WW3″ group. Then the experiment organisers get some of George IV’s parent’s DNA, and clone him a sibling if a coin comes heads. Everyone is (honestly) told the result of the coin flip.
This seems to have all the features of your example. Suppose you are told that there was no sibling clone. Then you can confidently say Probability(You exist [and know that George VI had exactly five siblings] | George VI had more than five siblings) = 0.
And yet the “anthropic” odds of being in the “WW3″ group remains 1:100. So something genuinely different is going on.
Whether you can apply the same reasoning to the anthropic cases is what is debated between SIA, SSA and my favourite ADT.