The Pinocchio paradox arises when Pinocchio says "My nose grows now" and is a version of the liar paradox.[1] The liar paradox is defined in philosophy and logic as the statement "This sentence is false." Any attempts to assign a classical binary truth value to this statement lead to a contradiction, or paradox. This occurs because if the statement "This sentence is false" is true, then it is false; this would mean that it is technically true, but also that it is false, and so on without end. Although the Pinocchio paradox belongs to the liar paradox tradition, it is a special case because it has no semantic predicates, as for example "My sentence is false" does.[2]
The Pinocchio paradox has nothing to do with Pinocchio being a known liar. If Pinocchio were to say "I am getting tired," this could be either true or false, but Pinocchio's sentence "My nose grows now" can be neither true nor false; hence this and only this sentence creates the Pinocchio (liar) paradox.