A formula in CycL or first-order predicate calculus is in conjunctive normal form (CNF) if it is a conjunction of disjunctions of literals. For example,
(#$and (#$or (#$not (#$isa ?C #$Cloud)) (#$colorOfObject ?C #$WhiteColor) (#$colorOfObject ?C #$GreyColor)) (#$or (#$not (#$isa ?C #$Cloud)) (#$physicalStructuralAttributes ?C #$Puffy)))
is in conjunctive normal form. For every CycL or FOPC formula, there is a logically equivalent formula that adheres to CNF.