Circular Definition include "header.inc"; ?> Definition Examples
  1. An animal is human if and only if it has human parents.
    (The term being defined is "human". But in order to find a human, we would need to find human parents. To find human parents we would already need to know what a human is.)

  2. A book is pornographic if and only if it contains pornography.
    (We would need to know what pornography is in order to tell whether a book is pornographic.)

Proof

References 13 August 1996