Comment on Boltzmann Brains and Anthropic Reference Classes (Updated)

Mon, 04 Jun 2012 20:27:12 GMT

Here's the structure of the purported problem in cosmology:

(1) Model X predicts that most observers with subjective experience identical to mine are Boltzmann brains.

(2) I am not a Boltzmann brain.

(3) The right way to reason anthropically is the SSA.

(4) The appropriate reference class used in the SSA must include all observers with subjective experience identical to mine.

CONCLUSION: Model X wrongly predicts that I'm a Boltzmann brain.

I am not attacking any of the first 3 premises. I am attacking the fourth. Attacking the fourth premise does not require me to establish that I'm not a Boltzmann brain. That's a separate premise in the original argument. It has already been granted by my opponent. So I don't see how assuming it, in an objection to the argument given above, amounts to writing my bottom line first.

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