public static FOLDomain crusadesDomain()
{
FOLDomain domain = new FOLDomain();
domain.addConstant("John");
domain.addConstant("Richard");
domain.addConstant("England");
domain.addConstant("Saladin");
domain.addConstant("Crown");
domain.addFunction("LeftLegOf");
domain.addFunction("BrotherOf");
domain.addFunction("EnemyOf");
domain.addFunction("LegsOf");
domain.addPredicate("King");
return domain;
}