oughts, we are little accustomed to contemplate the
subject in this manner, and this also enhances the difficulty. When,
however, the importance of speech is adequately considered, it will, I
think, be detected, that the terms which we employ as the
representatives of the perceptions of touch, smell, and taste, are the
only media by which they can be voluntarily recollected or communicated
to others; and, as signs of such perceptions, are equivalent to the
representations by the hand of those which have been perceived by the
organ of vision. To attempt the analysis of these silent deposits, to
endeavour to describe these bare perceptions, would be altogether
unavailing, because description implies language. In fact, it would be
an effort to detect the symmetry of the human frame, by loading it with
modern finery. The wonderful capacity which man exclusively enjoys,
both for the communication of his thoughts, and for the improvement of
his memory, in being enabled to acquire and transmit knowledge by
impregnating sound with intelligence, and more especially in exhibiting
its character embodied to the eye, leaves the rest of animated creation
at a prodigious distance. This endowment of language to man, whereby he
can, by an articulate sound, recall the perception of objects, (not
indeed equal to the sensorial impression, but sufficient for their
recollection, and also for the proof of their identity)--whereby he can
with equal intelligence exhibit their character to the eye, is
sufficient to explain of what the materials of his thoughts
consist:--and to prove that animals being unable to substitute a term
for their perceptions, are incapable of the process which we denominate
thought or reflection. To fathom this mystery, is perhaps impossible;
but, from attentively watching that which passeth within us,--from
considering the state of animals which want this endowment altogether,
it seems to be a law of our intellectual constitution, that our thoughts
or reflections can only consist of the terms which represent our
perceptions; and this is more evidently true, when we reflect on those
subjects which are of a general or abstract nature.

Whoever will attentively watch the operation of his own mind,--for this
subject admits of direct experiment,--will find that he employs terms
when he conducts the process of reflection. In order to afford a fair
trial, it is necessary that he should be alone, and subject to no
interruption