-*- mode:Text -*-
Copyright 1992 Patrick H. Winston.  All rights reserved.
Version 1.1, transferred from master disk on 21 Jan 93
 
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PURPOSE

Provides program support for Chapter 7, Rules and Rule Chaining.
Illustrates backward chaining via animal identification.

PERFORMANCE EXPERIMENT 1

Examine the file zoobk.exp.  Run the animal identification
experiments by typing the following command to your lisp system:

(load "zoobk.exp")

Alternatively, evaluate each Lisp expression in the file one at a
time, noting what each does.

PERFORMANCE EXPERIMENT 2

Try evaluating PROLOGlike expressions such as the following:

(chain '((? x) is a mammal))

(chain '((? _) is a mammal))

If you are asked if you want to see another answer, press comma
(,) (followed by a carriage return on UNIX systems).

PERFORMANCE EXPERIMENT 3

Change the result by editing the assertions describing the
animals in zoo.lsp.  Run Zookeeper again with your altered
assertions.

KNOWLEDGE ENGINEERING EXPERIMENTS

See the file zoofw.txt.