PsychologyToday | For as long as human animals have pondered how we might differ from nonhuman animals (hereafter animals for convenience) many ideas have come and gone. For example, it's been postulated that humans are created in the image of God and are the only rational beings. People vary in their opinions on whether we are the only animals who are created in the image of God and of course it's not a claim that can be proven or disproven. However, ample research has shown that animals are rational beings and that they also share with us many other traits that were once thought to be uniquely human, including manufacturing and using tools, having culture, having a sense of self, using complex systems of communication, producing art, and having rich and deep emotional lives and knowing right from wrong. Two traits that seem to separate us from other animals are we're the only animals who cook food and no other animals are as destructive and evil.
Now, it's been suggested that perhaps mental time travel and having a theory of mind are two uniquely human ways of thinking that separate us from other animals. This idea is put forth in a book called The Recursive Mind by Michael Corballis. Corballis argues that recursion is a uniquely human trait. In an excellent review of Corballis's book, anthropologist Barbara J. King makes many of his arguments palatable to a lay audience. So for example, she writes, "it's a unique human trick to communicate by embedding structures within other structures, as when one noun phrase in a sentence is made to contain another. An example of such linguistic recursion is furnished by Corballis. The non-recursive sentences 'Jane loves John'' and 'Jane flies aeroplanes' may be combined to produce the recursive sentence 'Jane, who flies aeroplanes, loves John'. Less interested in language than the mind itself, Corballis states flatly that recursion is 'the primary characteristic that distinguishes the human mind from that of other animals'".
Mental time travel and theory of mind are recursive ways of thinking. King goes on to write, "During mental time travel, an experience that we've had in the past or that we imagine for ourselves in the future is 'inserted into [our] present consciousness'. Similarly, in theory of mind, we insert what we believe to be someone else's state of mind into our own."
So, how do Corballis's ideas hold up given what we know about the behavior and cognitive capacities of animals?
Mental time travel and theory of mind are recursive ways of thinking. King goes on to write, "During mental time travel, an experience that we've had in the past or that we imagine for ourselves in the future is 'inserted into [our] present consciousness'. Similarly, in theory of mind, we insert what we believe to be someone else's state of mind into our own."
So, how do Corballis's ideas hold up given what we know about the behavior and cognitive capacities of animals?
