This is the XML schema for the Rule Language as defined by the RIF-Core dialect. The schema is based on the following EBNF for the RIF-Core Rule Language (prepared for generalization to the RIF-BLD and RIF-PRD Rule Languages): Document ::= IRIMETA? 'Document' '(' Base? Prefix* Import* Group? ')' Base ::= 'Base' '(' ANGLEBRACKIRI ')' Prefix ::= 'Prefix' '(' NCName ANGLEBRACKIRI ')' Import ::= IRIMETA? 'Import' '(' LOCATOR PROFILE? ')' Group ::= IRIMETA? 'Group' '(' (RULE | Group)* ')' RULE ::= (IRIMETA? 'Forall' Var+ '(' CLAUSE ')') | CLAUSE CLAUSE ::= Implies | ATOMIC Implies ::= IRIMETA? (ATOMIC | 'And' '(' ATOMIC* ')') ':-' FORMULA LOCATOR ::= ANGLEBRACKIRI PROFILE ::= ANGLEBRACKIRI Note that this is an extension of the syntax for the RIF-Core Condition Language (CoreCond.xsd).