linguistic growth. We see this complex process of
the interaction of language and thought actually taking place under our
eyes. The instrument makes possible the product, the product refines the
instrument. The birth of a new concept is invariably foreshadowed by a
more or less strained or extended use of old linguistic material; the
concept does not attain to individual and independent life until it has
found a distinctive linguistic embodiment. In most cases the new symbol
is but a thing wrought from linguistic material already in existence in
ways mapped out by crushingly despotic precedents. As soon as the word
is at hand, we instinctively feel, with something of a sigh of relief,
that the concept is ours for the handling. Not until we own the symbol
do we feel that we hold a key to the immediate knowledge or
understanding of the concept. Would we be so ready to die for "liberty,"
to struggle for "ideals," if the words themselves were not ringing
within us? And the word, as we know, is not only a key; it may also be a
fetter.

Language is primarily an auditory system of symbols. In so far as it is
articulated it is also a motor system, but the motor aspect of speech is
clearly secondary to the auditory. In normal individuals the impulse to
speech first takes effect in the sphere of auditory imagery and is then
transmitted to the motor nerves that control the organs of speech. The
motor processes and the accompanying motor feelings are not, however,
the end, the final resting point. They are merely a means and a control
leading to auditory perception in both speaker and hearer.
Communication, which is the very object of speech, is successfully
effected only when the hearer's auditory perceptions are translated into
the appropriate and intended flow of imagery or thought or both
combined. Hence the cycle of speech, in so far as we may look upon it as
a purely external instrument, begins and ends in the realm of sounds.
The concordance between the initial auditory imagery and the final
auditory perceptions is the social seal or warrant of the successful
issue of the process. As we have already seen, the typical course of
this process may undergo endless modifications or transfers into
equivalent systems without thereby losing its essential formal
characteristics.

The most important of these modifications is the abbreviation of the
speech process involved in thinking. This has doubtless many forms,
according to the s