What's the relationship between cooperation and understanding? I ask because I've been reading a paper about simulating cooperation that studies the way verbal cooperation aids understanding. (Carl Vogel, "Interaction of Levels ofCooperation and Group Cohesion in a Social Model of Language Evolution") The simulation took a naïve form, as is commonly imposed by efforts to mimic human interactions on a computer. When you think how much computational effort is required to support a machine playing chess or Jeopardy, you realize that it will be some time before even sophisticated ape interactions can be simulated, let alone plausible human conversations. Even so, these small efforts encourage a thought. Language is the keystone that brings cooperation and understanding together.
Generative linguistics tends to focus on the arch's understanding side. Chomsky and disciples even deny that language arose as a means of communication, putting all stress on the private understanding that comes from thinking syntactically. Language was later externalized and permitted cooperation.
The cooperative side has its energetic supporters too. Michael Tomasello is a leading spokesman for this side of the arch. For this school, language certainly began as a means of working together, changing from a gestural system of control to one of joint activity. Tomasello has been outspoken in his rejection of the idea that there are any language-specific universals, Chomsky's grail.
My own biases lean to the cooperative/communicative leg, but the other side has its points as well, and my explorations into speech origins persuade me that the only way to see the dynamics of language's evolutionary origins is to take it whole, with cooperation propping up understanding and understanding supporting cooperation.
The simulation uses "understand" in its narrowest sense of knowing the meaning of a word, as in table focuses attention on a table. But as I say, circumstances force them into a naïve approach, and language expands to expand one's understanding. There are a variety of things one can say while looking at a table, "Look at that table," being the most bland. Substitute the word monstrosity and understanding becomes a matter of shared taste. Use Pembroke and understanding requires some knowledge of the history of table making. Use bargain and a knowledge of prices becomes important. Thus, understanding words is much more than a vocabulary test. Dictionaries are the beginning, not the end point of understanding a word.
The simulation also uses cooperation in the narrow sense of explaining a word's meaning, as in 'this thing [tapping on it] is a table.' But again, we see that whenever verbal cooperation expands understanding it goes into the nature of words. "Why do you say monstrosity," seems likely to provoke some account of the speaker's taste. "You call a $200 card table a bargain," should also lead to learning.
Thus, we see the dynamics of language growth depend on both cooperation and understanding. Understanding why a $200 card table is a bargain depends on the cooperation of somebody who already understands. Meanwhile, cooperation requires s a common core language and a individual difference between speakers. As a minimal difference two speakers share a common language and one of the speakers also knows one extra usage. If the two speakers cooperate, both of them can end up knowing the same things. More likely, both speakers know different things and if they cooperate both can understand more than either of them could on their own.
This growth, of course, is the great mystery of human success. We know so much more than any other species, and yet we are born knowing so very little about the world. How do we do it? We are smarter than the apes, but there is a relationship between their intelligence and ours that enables us to recognize what apes are thinking. Their social behavior is also familiar and intelligible. At the individual level that may be enough to get by. But the success of the group reflects the combination of brains and community into a unit that makes the difference.Language connects those two elements and the resulting power has spread us around the world, taking the knowledge of our ancestors with us.