the sky indicating a
storm, immediately takes in sail, and makes all snug for the night. In
all these cases we perceive a principle within us, frequently operating
along with reason, but sometimes also without it, which prompts us to
apply our previous knowledge for our present comfort and advantage.[7]
The constant operation of such a principle in our nature, no matter by
what name it is called, leads us, as plainly as analogy and natural
phenomena can do, to conclude, that it ought to be carefully studied,
and assiduously cultivated in the young, during the period usually
assigned for their education.

When we carefully trace the operation of this principle in common life,
it appears that, in fact, the greater portion of our physical comforts
depends upon it. "Experience" is but another name for it. We find some
substances warmer, softer, harder, or more workable than others, and we
apply this knowledge by substituting one for another. The savage finds
the wigwam more convenient, or more easily come at, than a cave or a
crevice in a rock, and he builds a wigwam;--he finds a hut more durable
than a wigwam, and he substitutes a hut;--he at last finds a cottage
still more convenient, and he advances in his desires and his abilities
by his former experience, and he builds one.--In every advance, however,
it is the application of his previous knowledge that increases his
comforts, and tends to perpetuate them; and accordingly, as a proper
and a general application of the "moral sense," leads directly to
national _virtue_; so the proper and general application of this
principle of "common sense" goes to promote every kind of personal and
family _comfort_, as well as national _prosperity_. Its ramifications
pierce through every design and action of industry and genius. It is the
exercise of this principle alone which, in the worldly sense,
distinguishes the wise man from the fool; and which gives all the
superiority which is possessed by a civilized, over a savage community.
It is the chief guardian of our safety, and the parent of every personal
and domestic comfort. It is, in short, familiarity with its exercise
that imparts confidence to the philosopher, decision to the legislator,
dexterity to the artificer, and perfection to the artist. In each case
it is the accumulation of knowledge _put to use_, which makes the
distinction between one man and another; and it is by the aggregation of
such men that a nation becomes pr