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Cited by 1,946

The DOI matches its Crossref record; 1 of the 1 references it cites were found in a registry or an index.

CYC: a large-scale investment in knowledge infrastructure

Open access
Lenat, Douglas B.·1995·Communications of the ACM

Abstract

Since 1984, a person-century of effort has gone into building CYC, a universal schema of roughly 10 5 general concepts spanning human reality. Most of the time has been spent codifying knowledge about these concepts; approximately 10 6 commonsense axioms have been handcrafted for and entered into CYC's knowledge base, and millions more have been inferred and cached by CYC. This article examines the fundamental assumptions of doing such a large-scale project, reviews the technical lessons learned by the developers, and surveys the range of applications that are or soon will be enabled by the technology.

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Metadata

Authors
Lenat, D. B.
Venue
Communications of the ACM
Published
1995-11
Volume
38
Issue
11
Pages
33-38
ISSN
  • 0001-0782 (ISSN-L)
  • 1557-7317
OpenAlex
W2107658650
Cited by
1,946
References
1
FWCI
21.06
Type
journal article
Language
en
Open access
bronze

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CoChat. (2026). Citation check: CYC: a large-scale investment in knowledge infrastructure. https://app.cochat.ai/papers/10.1145/219717.219745
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Lenat, D. B. (1995). CYC: a large-scale investment in knowledge infrastructure. Communications of the ACM. https://doi.org/10.1145/219717.219745

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Semantic Scholar’s data is described in: Kinney, R., et al. (2023). The Semantic Scholar Open Data Platform. arXiv:2301.10140.