"The first language humans had was gestures. There was nothing primitive about this language that flowed from people’s hands, nothing we say now that could not be said in the endless array of movements possible with the fine bones of the fingers and wrists. The gestures were complex and subtle, involving a delicacy of motion that has since been lost completely.
During the Age of Silence, people communicated more, not less. Basic survival demanded that the hands were almost never still, and so it was only during sleep (and sometimes not even then) that people were not saying something or other. No distinction was made between the gestures of language and the gestures of life. The labor of building a house, say, or preparing a meal was no less an expression than making the sign for I love you or I feel serious. When a hand was used to shield one’s face when frightened by a loud noise something was being said, and when fingers were used to pick up what someone else had dropped something was being said; and even when the hands were at rest, that, too, was saying something. Naturally, there were misunderstandings. There were times when a finger might have been lifted to scratch a nose, and if casual eye contact was made with one’s lover just then, the lover might accidentally take it to be the gesture, not at all dissimilar, for ‘Now I realize I was wrong to love you’. These mistakes were heartbreaking. And yet, because people knew how easily they could happen, because they didn’t go round with the illusion that they understood perfectly the things other people said, they were used to interrupting each other to ask if they’d understood correctly. Sometimes these misunderstandings were even desirable, since they gave people a reason to say, ‘Forgive me’, I was only scratching my nose. Of course I know I’ve always been right to love you. Because of the frequency of these mistakes, over time the gesture for asking forgiveness evolved into the simplest form. Just to open your palm was to say: Forgive me."
(taken from "The History of Love" - Nicole Krauss)