Book excerpt: A research subject is shown a cartoon like the 1950 Canary Row--a classic Sylvester and Tweedy Bird caper that features Sylvester climbing up a downspout, swallowing a bowling ball and slamming into a brick wall. After watching the cartoon, the subject is videotaped recounting the story from memory to a listener who has not seen the cartoon. Painstaking analysis of the videotapes revealed that although the research subjects--children as well as adults, some neurologically impaired--represented a wide variety of linguistic groupings, the gestures of people speaking English and a half dozen other languages manifest the same principles. Relying on data from more than ten years of research, McNeill shows that gestures do not simply form a part of what is said and meant but have an impact on thought itself.