# Fitch's knowability axioms are incompatible with quantum theory

@article{Fraser2020FitchsKA, title={Fitch's knowability axioms are incompatible with quantum theory}, author={Patrick Fraser and Nuriya Nurgalieva and L{\'i}dia del Rio}, journal={arXiv: Quantum Physics}, year={2020} }

How can we consistently model the knowledge of the natural world provided by physical theories? Philosophers frequently use epistemic logic to model reasoning and knowledge abstractly, and to formally study the ramifications of epistemic assumptions. One famous example is Fitch's paradox, which begins with minimal knowledge axioms and derives the counter-intuitive result that "every agent knows every true statement." Accounting for knowledge that arises from physical theories complicates…

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