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. Even to-day man, at the beginning of his life, still finds himself in that relationship to language which was natural to all men in former times. The little child acquires the ability to speak through the imitation of sounds, becoming aware of them long before it understands the meaning accorded to the various groups of sounds in the artificial state of contemporary adult speech. That the child's attention should be directed solely to the sound, and not to the abstract meaning of the individual words, is indeed the prerequisite of learning to speak. If, says Reid, the child were to understand immediately the conceptual content of the words it hears, it would never learn to speak at all. When the adult of to-day uses language in its artificial state, words are only signs for things signified by them. As he speaks, his attention is directed exclusively towards this side of language; the pure sound of the words he uses remains outside the scope of his awareness. The little child, on the other hand, has no understanding of the meaning of words and therefore lives completely in the experience of pure sound. In the light of this, Reid comes to the conclusion, so important for what follows, that with the emergence of a certain form of consciousness, in this case that of the intellectual content of words, another form submerges, a form in which the experience of the pure sound of words prevails. The adult, while in one respect ahead of the child, yet in another is inferior, for the effect of this change is a definite impoverishment in soul-experience. Reid puts this as follows: