Ontologies and Worlds in Category Theory: Implications for Neural Systems


We propose category theory, the mathematical theory of structure, as a vehicle for defining ontologies in an unambiguous language with analytical and constructive features. Specifically, we apply categorical logic and model theory, based upon viewing an ontology as a sub-category of a category of theories expressed in a formal logic. In addition to providing mathematical rigor, this approach has several advantages. It allows the incremental analysis of ontologies by basing them in an interconnected hierarchy of theories, with an operation on the hierarchy that expresses the formation of complex theories from simple theories that express first principles. Another operation forms abstractions expressing the shared concepts in an array of theories. The use of categorical model theory makes possible the incremental analysis of possible worlds, or instances, for the theories, and the mapping of instances of a theory to instances of its more abstract parts. We describe the theoretical approach by applying it to the semantics of neural networks.

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Healy, M.J., Caudell, T.P. Ontologies and Worlds in Category Theory: Implications for Neural Systems. Axiomathes 16, 165–214 (2006). https://doi.org/10.1007/s10516-005-5474-1

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  • category
  • cognition
  • colimit
  • functor
  • limit
  • natural transformation
  • neural network
  • semantics