---
title: "An Interval-Based Representation of Temporal Knowledge"
authors:
  - "James F. Allen"
doi: ""
url: "https://ijcai.org/proceedings/1981/46"
pdf: "https://ijcai.org/proceedings/1981/0046.pdf"
venue: "Proceedings of the Seventh International Joint Conference on Artificial Intelligence"
year: 1981
pages: "221-225"
track: "Nowledge Representation"
keywords:
---

# An Interval-Based Representation of Temporal Knowledge

James F. Allen

*Proceedings of the Seventh International Joint Conference on Artificial Intelligence*, pages 221-225.

## Abstract

This paper describes a method for maintaining the relationships between temporal intervals in a hierarchical manner using constraint propagation techniques. The representation includes a notion of the present moment (i.e., "now"), and allows one to represent intervals that may extend indefinitely into the pasllfuture. This research was supported in part by the National Science Foundation under Grant Number IST-80-12418, and in part by the Office of Naval Research under Grant Number N00014-80-C-0197.