_Signs of affirmation or approval, and of negation or disapproval: nodding and shaking the head_.—I was curious to ascertain how far the common signs used by us in affirmation and negation were general throughout the world. These signs are indeed to a certain extent expressive of our feelings, as we give a vertical nod of approval with a smile to our children, when we approve of their conduct; and shake our heads laterally with a frown, when we disapprove. With infants, the first act of denial consists in refusing food; and I repeatedly noticed with my own infants, that they did so by withdrawing their heads laterally from the breast, or from anything offered them in a spoon. In accepting food and taking it into their mouths, they incline their heads forwards. Since making these observations I have been informed that the same idea had occurred to Charma.[1117] It deserves notice that in accepting or taking food, there is only a single movement forward, and a single nod implies an affirmation. On the other hand, in refusing food, especially if it be pressed on them, children frequently move their heads several times from side to side, as we do in shaking our heads in negation. Moreover, in the case of refusal, the head is not rarely thrown backwards, or the mouth is closed, so that these movements might likewise come to serve as signs of negation. Mr. Wedgwood remarks on this subject,[1118] that “when the voice is exerted with closed teeth or lips, it produces the sound of the letter _n_ or _m_. Hence we may account for the use of the particle _ne_ to signify negation, and possibly also of the Greek mh in the same sense.” That these signs are innate or instinctive, at least with Anglo-Saxons, is rendered highly probable by the blind and deaf Laura Bridgman “constantly accompanying her _yes_ with the common affirmative nod, and her _no_ with our negative shake of the head.” Had not Mr. Lieber stated to the contrary,[1119] I should have imagined that these gestures might have been acquired or learnt by her, considering her wonderful sense of touch and appreciation of the movements of others. With microcephalous idiots, who are so degraded that they never learn to speak, one of them is described by Vogt,[1120] as answering, when asked whether he wished for more food or drink, by inclining or shaking his head. Schmalz, in his remarkable dissertation on the education of the deaf and dumb, as well as of children raised only one degree above idiotcy, assumes that they can always both make and understand the common signs of affirmation and negation.[1121]