Recursion as the Key to the Human Mind
In this chapter, I argue that the ability to think recursively is what distin-guishes the human mind from the minds of other animals. The two mental activities that most obviously exhibit recursion are language and theory of
mind. Both have featured prominently in psychological research on the great apes over the past half century, with the consensus being that even our closest relatives, chimpanzees and bonobos, have proven incapable of either true language or fully developed theory of mind, although both claims have remained controversial. My contention is that although great apes are capable of some languagelike behavior and have some capacity to take the perspective of others the missing ingredient is recursion.