(_i.e._, in some mode of combination with B) shall be
capable; but again, if A + B cannot unlock the case, these in
combination with C shall do so. And if not A + B + C, then, perhaps,
shall A + B + C combined with D; and so on _ad infinitum_; or in other
words that pairs, or binaries, ternaries, quaternaries, and in that mode
of progression will furnish keys intricate enough to meet and to
decipher the wards of any lock in nature.

Now, in studying history, the difficulty is about the delicacy of the
lock, and the mode of applying the key. We doubt not that many readers
will view all this as false refinement. But hardly, if they had much
considered the real experimental cases in history. For instance, suppose
the condition of a people known as respects (1) civilization, as
respects (2) relation to the sovereign, (3) the prevailing mode of its
industry, (4) its special circumstances as to taxation, (5) its physical
conformation and temperament, (6) its local circumstances as to
neighbours warlike or not warlike, (7) the quality and depth of its
religion, (8) the framework of its jurisprudence, (9) the machinery by
which these laws are made to act, (10) the proportion of its towns to
its rural labour, and the particular action of its police; these and
many other items, elements, or secondary features of a people being
known, it yet remains unknown which of these leads, which is inert, and
of those which are not inert in what order they arrange their action.
The _principium movendi_, the central force which organizes and assigns
its place in the system to all the other forces, these are quite
undetermined by any mere arithmetical recitation of the agencies
concerned. Often these primary principles can be deduced only
tentatively, or by a regress to the steps, historically speaking,
through which they have arisen. Sometimes, for instance, the population,
as to its principle of expansion, and as to its rate, together with the
particular influence socially of the female sex, exercises the most
prodigious influence on the fortunes of a nation, and its movement
backwards or forwards. Sometimes again as in Greece (from the oriental
seclusion of women) these causes limit their own action, until they
become little more than names.

In such a case it is essential that the leading outlines at least should
be definite; that the coast line and the capes and bays should be
well-marked and clear, whatever may become of the inland wate