The following is a statement from Susan Wagner Cook:

Gestures are pervasive behaviors, yet they are often overlooked, perhaps because they are not as "fancy" as speech. Gestures are not part of a formal code, and their meaning depends on the available context. However, gesture may enable speakers and listeners to capitalize on just these properties. In particular, gesture may allow people to offload some of the cognitive effort required to produce and comprehend complex and abstract representations, perhaps by incorporating situated and embodied representations. This can have effects on speakers' use of working memory, speakers' memory for events, and children's learning of mathematical concepts.

As a life-long craftsman, and teacher of manual arts, the current work in examining the role of gesture in communication and thought provides an important layer of evidence that there is so much more going on in our hands, and in the relationship between our hands and brains than modern schooling allows to unfold.

In essence, the movement of the hands facilitates the movement and development of thought, and to leave the hands stilled is the failing of American education. Once again, I stretch the thinking of Jean Jacques Rousseau: Put a young woman in a woodshop, her hands will will work to the advantage of her brain. She will become a philosopher while thinking herself only a craftsman.