 The number of possible factors which may disturb a bird’s flying capability is potentially infinite. In other words, for every condition \(C\) which excludes a finite list of such factors the completed law “All birds satisfying \(C\) can fly” will still have to face further exceptions—hence, a strict completion of this law is impossible. Exclusive cp-laws of this sort are called indefinite exclusive cp-laws, or in the terminology of Earman, Roberts and Smith (2002), non-lazy cp-laws.