Parametricity, automorphisms of the universe, and excluded middle

نویسندگان

  • Auke Bart Booij
  • Martín Hötzel Escardó
  • Peter LeFanu Lumsdaine
  • Michael Shulman
چکیده

It is known that one can construct non-parametric functions by assuming classical axioms. Our work is a converse to that: we prove classical axioms in dependent type theory assuming speci€c instances of non-parametricity. We also address the interaction between classical axioms and the existence of automorphisms of a type universe. We work over intensional Martin-Löf dependent type theory, and for some results assume further principles including function extensionality, propositional extensionality, propositional truncation, and the univalence axiom.

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عنوان ژورنال:
  • CoRR

دوره abs/1701.05617  شماره 

صفحات  -

تاریخ انتشار 2017