---
title: "Extended Plausible Inference"
authors:
  - "Leonard Friedman"
doi: ""
url: "https://ijcai.org/proceedings/1981/93"
pdf: "https://ijcai.org/proceedings/1981/0093.pdf"
venue: "Proceedings of the Seventh International Joint Conference on Artificial Intelligence"
year: 1981
pages: "487-494"
track: "Theoretical Foundations"
keywords:
---

# Extended Plausible Inference

Leonard Friedman

*Proceedings of the Seventh International Joint Conference on Artificial Intelligence*, pages 487-494.

## Abstract

A generalized theory of plausible inference has been developed, extended to arbitrary expressions of propositional calculus from Shortliffe and Buchanan's original MYCIN formulation. The theory represents uncertainty of belief, and invokes four rules of inference, instead of the two of standard logic. Areas of application include diagnostic problems and deciding between alternative hypotheses. The theory has been implemented in the PI system. The intended area of application for PI is the trouble-shooting of a failed spacecraft, and the solution to a simplified problem drawn from this area is described.