k in words. If you ask me to
define reason, I answer as before that this can no more be done than
thought, truth or motion can be defined. Who has answered the
question, "What is truth?" Man cannot see God and live. We cannot
go so far back upon ourselves as to undermine our own foundations;
if we try to do so we topple over, and lose that very reason about
which we vainly try to reason. If we let the foundations be, we
know well enough that they are there, and we can build upon them in
all security. We cannot, then, define reason nor crib, cabin and
confine it within a thus-far-shalt-thou-go-and-no-further. Who can
define heat or cold, or night or day? Yet, so long as we hold fast
by current consent, our chances of error for want of better
definition are so small that no sensible person will consider them.
In like manner, if we hold by current consent or common sense, which
is the same thing, about reason, we shall not find the want of an
academic definition hinder us from a reasonable conclusion. What
nurse or mother will doubt that her infant child can reason within
the limits of its own experience, long before it can formulate its
reason in articulately worded thought? If the development of any
given animal is, as our opponents themselves admit, an epitome of
the history of its whole anterior development, surely the fact that
speech is an accomplishment acquired after birth so artificially
that children who have gone wild in the woods lose it if they have
ever learned it, points to the conclusion that man's ancestors only
learned to express themselves in articulate language at a
comparatively recent period. Granted that they learn to think and
reason continually the more and more fully for having done so, will
common sense permit us to suppose that they could neither think nor
reason at all till they could convey their ideas in words?

I will return later to the reason of the lower animals, but will now
deal with the question what it is that constitutes language in the
most comprehensive sense that can be properly attached to it. I
have said already that language to be language at all must not only
convey fairly definite coherent ideas, but must also convey them to
another living being. Whenever two living beings have conveyed and
received ideas, there has been language, whether looks or gestures
or words spoken or written have been the vehicle by means of which
the ideas have travelled. Some ideas cr