This is a letter I wrote to Michael C. Corballis after reading something he wrote in New Scientist. He wrote a longer article on the same subject in American Scientist (May-June 2007). Michael Corballis is a professor in Psychology at Auckland University. At the end of this posting I include his response. The epiphany I mention (below) is possibly the only original idea in this entire blog. Everything else is either borrowed, stolen or adapted from other people, or independently derived, which still doesn't make it original.
Dear Professor Corballis
I read your article on recursive thinking in New Scientist (1 September 2007) and it reminded me of an epiphany I had when I was studying philosophy about 10 years ago. It occurred to me that what separated us from other species, more than anything else, was our ability to form concepts within concepts ad infinitum, which is similar to what you describe as embedded recursion, though not quite the same.
If one takes writing, as I’m doing now, we have individual words that have their own meanings. But we can create sentences of those words that then have a meaning beyond the individual words, and then we can create a string of sentences that eventually may form an overarching argument or a story. And perhaps it was with storytelling that we first exercised this ability. But we do it with everything: music, architecture, engineering and even mathematics. We take individual parts assemble them mentally to form a larger part that has a different function than the individual parts. I think mathematics is the best example because it is so obviously structured this way while we are learning it. Yet, I believe it is through art that we originally developed this unique skill.
But this was not the epiphany. The epiphany was realising that nature also consists of different levels of entities within entities. If you take an individual organic cell, it is like a miniature world that has a function completely different to the collection of cells, that, combined, create an individual organism like a human, which has another function altogether. And it occurred to me that we are uniquely suited to comprehend nature because we have the ability to conceptualise entities within entities in exactly the same way that nature manifests itself. This is why we have become the self-designated interpreters of the universe, or, at least, the only ones we know of.
On the subject of language, I’ve often wondered how we would think without language, and the obvious answer is we would think in images as we do in our dreams. Again, I wondered if our artwork was our first attempt to project this imagery as a form of expression, communication and social bonding. The language of dreams is imagery and metaphor, so I am not surprised that when we read stories we can so readily create our own images in our heads, and this is one of the reasons that cinema and video, in all its manifestations, hasn’t managed to kill off books. The other reason is that a book can take you inside the character’s head in a way that movies can’t. In the case of a movie you depend on the actor to interpret it for you. I know I’m going off the track a bit here, but I’m speaking from the perspective of someone who writes fiction.
In science and engineering we attempt to visualise things when we explain them or interpret them. Engineers will always draw a picture when they try to explain something. Metaphor is an analogy that allows us to communicate something new by employing something already known. My point being that we are essentially visual creatures, and that is our medium of choice when we strive to comprehend the world. I notice that you believe our earliest language was in sign. I understand that we use our hands when we talk because it helps us to create the concept in our head that we are trying to communicate, rather than for the benefit of the listener. Is this the basis of your thesis: that thinking with our hands preceded thinking with language?
Below is Michael Corballis's response.
I agree with you entirely, and I also like your epiphany, which I’ll think more about.
The idea that language arose from manual gestures is based on a number of considerations: (1) apes can be taught something approximating sign language, but can’t be taught to speak; (2) the brain areas involved in speech in humans are involved in manual action in primates; (3) the sign languages of the deaf are fully expressive languages; and (4) we all gesture as we speak. I agree that gesturing may help us form concepts while we speak, but I suspect that our gesturing also reflects an earlier mode of communication.