precise and complete set.

VI. We can now sketch the plan of historical construction in a way which
will determine the series of synthetic operations necessary to raise the
edifice.

The critical analysis of the documents has supplied the
materials--historical facts still in a state of dispersion. We begin by
_imagining_ these facts on the model of what we suppose to be the
analogous facts of the present; by combining elements taken from reality
at different points, we endeavour to form a mental image which shall
resemble as nearly as possible that which would have been produced by
direct observation of the past event. This is the first operation,
inseparable in practice from the reading of the documents. Considering
that it will be enough to have indicated its nature here,[184] we have
refrained from devoting a special chapter to it.

The facts having been thus imagined, we _group_ them according to
schemes of classification devised on the model of a body of facts which
we have observed directly, and which we suppose analogous to the body of
past facts under consideration. This is the second operation; it is
performed by the aid of systematic questions, and its result is to
divide the mass of historical facts into homogeneous portions which we
afterwards form into groups until the entire history of the past has
been systematically arranged according to a general scheme.

When we have arranged in this scheme the facts taken from the documents,
there remain gaps whose extent is always considerable, and is enormous
for those parts of history in regard to which documents are scanty. We
endeavour to fill some of these gaps by _reasoning_ based on the facts
which are known. This is (or should be) the third operation; it
increases the sum of historical knowledge by an application of logic.

We still possess nothing but a mass of facts placed side by side in a
scheme of classification. We have to condense them into _formulae_, in
order to deduce their general characteristics and their relation to each
other. This is the fourth operation; it leads to the final conclusions
of history, and crowns the work of historical construction from the
scientific point of view.

But as historical knowledge, which is by nature complex and unwieldy, is
exceptionally difficult to communicate, we still have to look for the
methods of expounding historical results in appropriate form.

VII. This series of operations, easy to conceive