Language provides a remarkably clear window onto the complex workings of the human psyche and the human brain. By studying people’s names for animals and foods, we can learn how they think about the biological world. By examining and testing people who have suffered from a brain lesion, we can identify parts of the brain that are important for particular cognitive and emotional functions. By studying infant babbling, we can understand how the brain comes to control the vocal apparatus. By observing how people learn a second language, we can come to understand ways in which the mind and brain change over time and experience. By studying how people describe their solutions to problems, we can track the details of problem solving in activities, such as chess, architecture, medicine, and law. In these and many other ways, we can use language as a window onto the mind and the brain