The nature of language is the nature of human thought and human action, for language is no more nor less than the tool of both of these aspects of human nature. A word is either the shadow of an act or of an idea. Verbal sounds have no meaning in themselves. They are the channels, the media for the expression or communication of that which lies outside of themselves. Plato has made clear to us how easy it is to deceive ourselves with words, to labor under an impression that just because we can utter a sound we also necessarily know what we are talking about.
Words may be empty vessels and pour out no more than hollow sounds. We find it simple to define some words and extremely difficult to define others. The reason is that the definition of a word is the experience it records. Hence the definiteness of a definition of a word is in proportion to the vividness of the experience, its meaning. We readily define chair because of our frequent experience with the object of which the sound is a symbol. We define it in terms of our experience, as an object to sit in. But a definition of terms like truth, or virtue, or honesty, or beauty is a most severe trial because of the haziness or complete lack of experiences of this nature. What, then, is the source of the meaning of words? What is the relationship between words, things, and actions?
Meaning begins as behavior and culminates as language. There is meaning as behavior and meaning as language. And meaning as language is the consequence of meaning as behavior. There can be behavior without language, but there could be no meaning as language without behavior. The source of the meaning of words is thus behavior. The relationship between behavior and things gives rise to the meaning of words. Meaning is inherent neither in things nor in words, but both things and words obtain their meaning from behavior.
What is the meaning of a thing or a situation? The cat sees the dog and it runs away. It sees a saucer of milk and it runs towards it. I see one person approaching me and I smile. I see another coming towards me and I frown. The meaning of the dog to the cat is to run away. The meaning of the saucer of milk is to run towards it. The meaning of one person to me is to smile, of another person to frown.
If the dog or milk aroused no action in the cat they would have no meaning, as dog or milk. If the two persons aroused no action in me they would have no meaning as persons. From these simple illustrations we conclude that whenever a thing or situation becomes a cue, a signal, for a definite reaction, that thing or situation becomes meaningful, and the meaning of the thing or situation is the behavior it provokes. The thing or situation may have different meanings on different occasions, but on each occasion its meaning is the behavior. The behavior may be outer or inner, muscular or mental, an act or a thought. But things or situations that cause neither inner nor outer behavior possess no meaning.
Now what about the relationship between sounds and things?
The cat hears the bark of the dog and it runs away from the source of the sound. It hears some one utter the sound "milk" and it runs to the place where it usually finds the saucer. I hear the voice of one person and I smile. I hear that of another and I frown. What is the meaning of the sounds? Again, the behavior provoked by them. The sounds have become substitutes for the thing or situation, and the meaning of the sounds is that of the thing or situation. A word is thus a sound that has become a substitute for a thing or a situation. Language is a substitute stimulus for behavior, its meaning being the behavior produced by the original stimulus. When the world does not stimulate mental or muscular activity, when it does not recall past experience of some sort, it has no meaning. A foreign language with which we are unfamiliar has no meaning because the sounds do not serve as clues for past events.
Language is therefore, in its basic nature, a utility, an instrument, a tool of the business of living. It is one with things and situations of the everyday world of life. We could get along without it, but it is a great convenience to which we have become so accustomed that we deem it a necessity. The business of mere existence could readily go on, as it does among animals, without language. We would even save ourselves a great deal of trouble in not deceiving ourselves and others by the use of empty sounds.