Rule technical terms
Conclusion
A conclusion states something that can be deduced (taken as true) if the rule's conditions are found to be true.
In Forward and Easy-f rules, the conclusion appears at the end of the rule (between THEN and '.').
In Backward and Easy-b rules, the conclusion appears at the start of the rule (before IF).
Condition
A condition states something that must be shown to be true in order to deduce the truth of a rule's conclusion.
A rule may have many conditions separated by AND or '&'.
In Forward and Easy-f rules, conditions appear at the start of the rule between IF and THEN.
In Backward and Easy-b rules, conditions appear at the end of the rule between IF and '.'.
Feature
A feature is an expression of the form
attribute IS value
or attribute = value
or attribute ARE value
Note that a feature must contain one of IS, '=', ARE.
An attribute and a value may consist of any text excluding IS, '=', ARE and a few other reserved symbols.
The conditions and conclusions of Forward and Backward rules take the form of features.
Proposition
A proposition is an expression made up of any text.
No special recognition is given to the symbols IS, '=', ARE and these may be used freely. A few other symbols are reserved and must be avoided.
The conditions and conclusions of Easy-f and Easy-b rules take the form of propositions.