The only difference is that in this case the ability to hear results in the addition of a third form of movements to the mimetic and pantomimetic movements. These are the articulatory movements, and since they are much more easily perceived, and capable of incomparably more various modification, it must of necessity follow that [p. 300] they, soon exceed the others in importance. But just as mimetic and pantomimetic gestures owe their intelligibility to the immediate relation that exists between the character of the movement and its meaning,-so here also we must presuppose a like relation between the original articulatory movement and its meaning.
Then, too,, it is not improbable that articulation was at first aided by accompanying mimetic and pantomimetic gestures. As evidence for this view we have the unrestrained use of such gestures by savages, and the important part they play in the child's learning to speak.. The development of articulate language is, accordingly, in all probability to be thought of as a process of differentiation, in which the articulatory movements have gradually gained the permanent ascendency over a number of different variable expressive movements that originally attended them, and have dispensed with these auxiliary movements as they themselves gained a sufficient degree of fixity.
Psychologically the process may be divided into two acts. The first consists in the expressive movements of the individual member of the community.
These are impulsive volitional acts, among which the movements of the vocal organs gain the ascendency over the others in the effort of the individual to communicate with his fellows. The second consists in the subsequent associations between sound and idea, which gradually become more fixed, and spread from the centres where they originated through wider circles of society.
5. From the first there are other physical and psychical conditions that take part in the formation of language and produce continual and unceasing modifications in its components. Such modifications may be divided into two classes: those of sound and those of meaning.
The first class have their physiological cause in the gradual changes that take place in the physical structure of [p. 301] the vocal organs.
These changes are, to a great extent at least, either physically or psycho-physically conditioned. They come partly from the general changes which the transition from a savage to a civilized condition produces in the physical organism, partly from the special conditions that result from increased practice in the execution of articulatory movements. Many phenomena go to show that the gradually increasing rapidity of articulation is of especially great influence. Then, too, the words that are in any way analogous effect one another in a way that indicates the interference of the psychical factor of association.
As the change in sound modifies the outer form of words, so the change in meaning modifies their inner content. The original association between a word and the idea it expresses is modified by the substitution of another different idea. This process of substitution may be several times repeated with the same word. The change in the meaning of words depends, therefore, on a gradual modification of the associative conditions determining the ideational complication that shall arise in the fixation-point of consciousness when a word is heard or spoken. It may, accordingly, be briefly defined as a shifting of the ideational component of the complications connected with articulate sounds (p. 234).
These changes in the sound and meaning of words operate together in bringing about the gradual disappearance of the originally necessary relation between sound and meaning, so that a word finally- comes to be looked upon as a mere external sign of the idea. This process is so complete that even those verbal forms in which this relation seems to be still retained, onomatopoetic words, appear to be, for the most part, products of a relatively late and secondary assimilative process which seeks to reestablish the lost affinity between sound and meaning. [p. 302]
Another important consequence of this combined action of changes in sound and meaning, is to be found in the fact that many words gradually lose entirely their original concrete sensible significance, and become signs of general concepts and means for the expression of the apperceptive relating and comparing functions and their products. In this way abstract thinking is developed. It would be impossible without the change in meaning of words upon which it is based and it is, therefore, a product of the psychical and psycho-physical interactions from which the progressive development of language results.
6. Just as the components of language, or words, are undergoing a continual development in sound and meaning, so in the same way, though generally more slowly, changes are going on in the combinations of these components into complete wholes, that is, in sentences. No language can be thought of without some such syntactic order of its words. Sentences and words are, therefore, equally primitive as psychological forms of thought.