Introduction

1.  Conceptual analysis of abduction

2.  Knowledge-based systems and the Science of AI

3.  Two RED system - abduction machines 1 and 2

4.  Generalizing the control strategy - machine 3

5.  More kinds of knowledge: two diagnostic systems

6.  Better task analysis, better strategy - machine 4

7.  The computational complexity of abduction

8.  Two more diagnostic systems

9.  Better task definition, better strategy - machine 5

10. Perception and language understanding

A.  Truth seekers

B.  Plausibility