arly approaching the truth. Montesquieu says, the decay of the
Roman empire was the natural consequence of its extension. This sounds
well, and looks like an aphorism: but if the matter be considered with
attention, it will be found that it is _vox et praeterea nihil_. Those
who, with so much complacency, rest in the belief that the fall of the
Roman empire was the natural result of its extension, forget that its
_greatest prosperity was coexistent with that very extension_. It is
impossible to hold that the decay of the empire was the consequence of
its magnitude, when the glorious era of the Antonines, during which it
numbered a hundred and twenty millions of inhabitants under its rule,
and embraced nearly the whole known habitable globe within its dominion,
immediately succeeded its greatest extension by the victories, unhappily
to us so little known, of Trajan.

More recent writers, seeing that Montesquieu's aphorism was a vague
proposition which meant nothing, have gone a step further, and
approached much nearer to the real explanation of the phenomenon.
Guizot, Sismondi, and Michelet have concurred in assigning as the real
cause of the decay of the Roman empire, the prevalence of slavery among
its working population, and the great and increasing weight of taxes to
support the imperial government. There can be no doubt that these were
most powerful causes of weakness; and that they stand prominently forth
from the facts recorded by contemporary annalists, as the immediate and
_visible_ causes of the decline of the empire. The history of these
melancholy periods is full of eternal complaints, that men could not be
got to fill the legions, nor taxes to replenish the treasury; that the
army had to be recruited from the semi-barbarous tribes on the frontier;
and that vast tracts of fertile land in the heart of the empire relapsed
into a state of nature, or were devoted only to pasturage, from the
impossibility of finding cultivators who either would till the land, or
could afford to pay the taxes with which it was charged. Doubtless the
large proportion--at least a half, perhaps nearly two-thirds--of the
people who were slaves, must have weakened the elements of strength in
the empire; and the enormous weight of the direct taxes, so grievously
felt and loudly complained of,[5] must have paralysed, to a very great
degree, both the industry of the people and the resources of government.
But a very little consideration mus