Douglas B. Lenat – Communications of the ACM

Research and Advances Nov 1 1995

CYC: a large-scale investment in knowledge infrastructure

Since 1984, a person-century of effort has gone into building CYC, a universal schema of roughly 105 general concepts spanning human reality. Most of the time has been spent codifying knowledge about these concepts; approximately 106 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.

Architecture and Hardware

Author Archives

Research and Advances Jul 1 1994

Enabling agents to work together

Artificial Intelligence and Machine Learning

Research and Advances Aug 1 1990

Cyc: toward programs with common sense

Cyc is a bold attempt to assemble a massive knowledge base (on the order of 108 axioms) spanning human consensus knowledge. This article examines the need for such an undertaking and reviews the authos' efforts over the past five years to begin its construction. The methodology and history of the project are briefly discussed, followed by a more developed treatment of the current state of the representation language used (epistemological level), techniques for efficient inferencing and default reasoning (heuristic level), and the content and organization of the knowledge base.

Artificial Intelligence and Machine Learning

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