“Where the right hemisphere can see that metaphor is the only way to preserve the link between language and the world it refers to, the left hemisphere sees it as either a lie (Locke, expressing Enlightenment disdain, called metaphors ‘perfect cheats’) or as a distracting ornament; and connotation as a limitation, since in the interests of certainty the left hemisphere prefers single meanings.”

— Iain McGilchrist, The Master and His Emissary, p. 118

“I mentioned earlier that there were those who believed that language arose, not from music, but from gesture. There is, however, no necessary conflict between such beliefs. Music is deeply gestural in nature: dance and the body are everywhere implied in it. Even when we do not move, music activates the brain’s motor cortex. Music is a holistic medium, ‘multimodal’ as Mithen puts it, not limited to a distinct modality of experience. To the extent that the origins of language lie in music, they lie in a certain sort of gesture, that of dance: social, non-purposive (‘useless’). When language began to shift hemispheres, and separate itself from music, to become the referential, verbal medium that we now recognize by the term, it aligned itself with a different sort of gesture, that of grasp, which is, by contrast, individualistic and purposive, and became limited to one modality.”

— Iain McGilchrist, The Master and His Emissary, p. 119