fertility of
explanation which distinguish the _Esprit des Lois_, but it has been
well regarded as a kind of preliminary exercise for that great work.
Montesquieu here treats an extensive but homogeneous and manageable
subject from the point of view of philosophical history, after a method
which had been partially tried by Bossuet, and systematically arranged
by Vico in Italy, but which was not fully developed till Turgot's time.
That is to say, his object is not merely to exhibit, but to explain the
facts, and to explain them on general principles applicable with due
modifications to other times and other histories. Accordingly, the style
of the _Grandeur et Decadence_ is as grave and dignified as that of the
_Lettres Persanes_ is lively and malicious. It is sometimes a little too
sententious in tone, and suffers from the habit, induced probably by
_Pensee_-writing, of composing in very brief paragraphs. But it is an
excellent example of its kind, and especially remarkable for the extreme
clearness and lucidity with which the march and sequence of events in
the gross is exhibited.

[Sidenote: Esprit des Lois.]

The _Esprit des Lois_ is, however, a far greater book than either of
these, and far more original. The title may be thought to be not
altogether happy, and indeed rather ambiguous, because it does not of
itself suggest the extremely wide sense in which the word law is
intended to be taken. An exact if cumbrous title for the book would be
'On the Relation of Human Laws and Customs to the Laws of Nature.' The
author begins somewhat formally with the old distinction of politics
into democracy, aristocracy, and monarchy. He discusses the principles
of each and their bearings on education, on positive law, on social
conditions, on military strength, offensive and defensive, on individual
liberty, on taxation and finance. Then an abrupt return is made from the
effects to the causes of constitutions and polity. The theory of the
influence of physical conditions, and especially of climate, on
political and social institutions--a theory which is perhaps more than
any other identified with the book--receives special attention, and a
somewhat disproportionate space is given to the question of slavery in
connection with it. From climate Montesquieu passes to the nature of
the soil, as in its turn affecting civil polity. He then attacks the
subject of manners and customs as distinct from laws, of trade and
commerce, of the