Reid notes as a fundamental characteristic of human language that it includes two distinct elements: first, the purely acoustic element, represented by the sheer succession of sounds, and secondly the variety of meanings represented by various groups of sounds, meanings which seem to have nothing to do with the sounds as such. This state of language, where the sound-value of the word and its value as a sign to denote a thing signified by it, have little or nothing to do with one another, is certainly not the primeval one. In the contemporary state of language, which Reid calls artificial language, we must see a development from a former condition, which Reid calls natural language. So long as this latter condition obtained, man expressed in the sound itself what he felt impelled to communicate to his fellows. In those days sound was not merely an abstract sign, but a gesture, which moreover was accompanied and supported by the gestures of the limbs.