• Patrick Schultz
  • David I. Spivak
Part of the Progress in Computer Science and Applied Logic book series (PCS, volume 29)


In Chap. 4, we explained a connection between toposes, type theory, and logic. We also discussed modalities and numeric types in an arbitrary topos. In the current chapter, we will lay out the signature—meaning the atomic types, atomic terms, and axioms—for our specific topos, \(\mathcal {B}\). It turns out that our signature consists of no atomic types, one atomic term, and ten axioms.


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Copyright information

© The Author(s) 2019

Authors and Affiliations

  • Patrick Schultz
    • 1
  • David I. Spivak
    • 1
  1. 1.Massachusetts Institute of TechnologyCambridgeUSA

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