Ripple-down rules are an incremental approach to knowledge acquisition and covers a family of techniques.
Knowledge acquisition tools, similar to those provided by Teiresias were developed to find and help modify the conflicting rules.
The tools would display the rules fired by each case and suggestions to "edit" the knowledge to remove the conflicts.
In the RDR framework, the human expert's knowledge is acquired based on the current context and is added incrementally.
Compton and Jansen argued that the expert's knowledge is to some extent 'made up' to justify why she was right, not to explain how she reached this right interpretation (or conclusion).
For example, rule Child-1 is added to correct classification of case [OutLook="SUNNY", Temperature="COOL", Wind="WINDY", Humidity="HIGH", ForeCast="STORM", Play="SQUASH"].