Roy Baumeister
The Cultural Animal
Consider the interactions between mother and baby. In many species, mothers and babies attend to each other and manage to communicate about what the baby needs and how the mother can provide it. In this, human beings are nothing special. But Tomasello has concluded that we are the only species in which mothers and babies signal to each other the presence of something else in the environment simply for the sake of enabling them to perceive it together. 'Look!' is universally one of the earliest words that human mothers speak to babies and one of the first that babies use to communicate with mothers. Calling someone's attention to a bright light, pretty color, or peculiar flower does not seem all that remarkable, unless you realize that it is beyond what almost any other species can accomplish. (I have tried to get my various dogs to look at something, but typically no amount of pointing, gesturing, or shouting can get a dog to look where you want. They just stare at me stupidly, while outside the window the rabbits scamper by with impunity.) In fact, Tomasello emphasizes, human babies past the age of about 9 months often will spontaneously turn to see. what Mama is looking at, without being instructed or exhorted to do so. To do this, they must apparently understand that Mama has a mind that is perceiving something and that they can perceive that same thing by looking in the same direction.
What the human baby shares with other humans is not just the capability of joint attention, although that is hugely important. A related ability is the recognition of intention. Because you know that other humans have minds and inner mental states like you have, you quickly learn to attribute intentions to them, just as your own behavior is organized by intention. You choose a goal and then perform actions that are designed to bring about that goal—and, once you realize that other human beings are similar to you, you can interpret their actions as intentional.
Recent findings from neuroscience suggest that the human brain has an innate capability and tendency to read intention into the behavior of others. A Swedish researcher developed a procedure by which he attached lightbulbs to a person's joints and then filmed the person moving around in a dark room. All that showed up on the film was a bunch of moving points of light. When other people watched this film, they quickly and effortlessly recognized the light movements as indicating intentional movement by a human being. Even human babies as young as 3 months could tell the difference between these 'human' light movements and a pattern of random movements with the same number of points of light. Other studies show that the brain seems to use its own experiences with movement to be able to infer intention from the movements of other people. Taken together, these studies indicate that the human brain is designed to perceive human movement in a way that leads to inferring intentions.
Other work has confirmed that the human brain seems hard-wired to perceive intention. In these, 18-month-old human babies watched either a human model or a mechanical device trying but failing to perform various actions, such as pulling something apart. The infants who watched a person fail would imitate the action themselves and succeed. Those who watched a mechanical device attempt the same act were not moved to copy or improve on it. Thus, even very young human beings interpret identical acts differently depending on whether they are performed by a fellow human being or by something else. In Tomasello's terms, we 'identify with our species' much more than any other creatures do.
Identifying with our species is not absolutely crucial to communication, but communication cannot get nearly as far without it as with it. An animal might bark or chirp out a warning to alert family members to the presence of food or the presence of a predator, and these patterns can be sustained simply because they improve the chances that one's partners will continue to be around. Identifying with the species entails recognizing that others have inner mental states similar to ones own. Chimps and other smart animals generally fail these tests. For example, they do not distinguish between fellows who are ignorant versus those who are knowledgeable about some crucial fact. In some studies, a chimp has to choose another chimp to get a reward for it, and the chooser has observed that one fellow chimp saw where the food was hidden while another chimp didn't see it. Obviously, only the first fellow will be of any help, and so that's the one to choose. But the choosing chimp seems to choose at random upon which of the other fellows to rely, disregarding the crucial fact that only one of the others has the requisite knowledge.
Even more important, chimps do not seem to share knowledge deliberately. They seem to lack the capacity to recognize that communicative behaviors are intended to share some useful information.
