A Bayesian analysis of self-undermining arguments in physics

Abstract

Some theories in physics seem to be ‘self-undermining’: that is, if they are correct, we are probably mistaken about the evidence that apparently supports them. For instance, certain cosmological theories have the apparent consequence that most observers are so-called ‘Boltzmann brains’, which exist only momentarily and whose apparent experiences and memories are not veridical. I provide a Bayesian analysis to demonstrate why theories of this kind are not after all supported by the apparent evidence in their favor, taking advantage of the split between ‘primary evidence’, which directly supports a theory, and ‘proximal evidence’, which is our evidence (largely records and testimony) for the primary evidence. contexts in physics generate , or