 Karel Lambert (1960) coined the term ‘free logic’ as an abbreviation for ‘logic free of existence assumptions with respect to its terms, singular and general’. General terms are predicates. Lambert was suggesting that just as classical predicate logic generalized Aristotelian logic by, inter alia, admitting predicates that are satisfied by no existing thing (‘is a Martian’, ‘is non-self-identical’, ‘travels faster than light’), so free logic generalizes classical predicate logic by admitting singular terms that denote no existing thing (‘Aphrodite’, ‘the greatest integer’, ‘the present king of France’).