Observer-Relative Chances In Anthropic Reasoning?

  title={Observer-Relative Chances In Anthropic Reasoning?},
  author={Nick Bostrom},
John Leslie presents a thought experiment to show that chances are sometimes observer-relative in a paradoxical way. The pivotal assumption in his argument – a version of the weak anthropic principle – is the same as the one used to get the disturbing Doomsday argument off the ground. I show that Leslie's thought experiment trades on the sense/reference ambiguity and is fallacious. I then describe a related case where chances are observer-relative in an interesting way. But not in a paradoxical… 
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