The decline of Rome was the natural and inevitable effect of immoderate greatness. Prosperity ripened the principle of decay; the cause of the destruction multiplied with the extent of conquest; and, as soon as time or accident and removed the artificial supports, the stupendous fabric yielded to the pressure of its own weight. The story of the ruin is simple and obvious: and instead of inquiring why the Roman Empire was destroyed we should rather be surprised that it has subsisted for so long.

Extreme distress, which unites the virtue of a free people, imbitters the factions of a declining monarchy.

The laws of war, that restrain the exercise of national rapine and murder, are founded on two principles of substantial interest: the knowledge of the permanent benefits which may be obtained by a moderate use of conquest, and a just apprehension lest the desolation which we inflict on the enemy's country may be retaliated on our own. But these considerations of hope and fear are almost unknown in the pastoral state of nations.

The image of a free constitution was preserved with decent reverence: the Roman senate appeared to possess the sovereign authority, and devolved on the emperors all the executive powers of government. During a happy period (A.D. 98-180) of more than fourscore years, the public administration was conducted by the virtue and abilities of Nerva, Trajan, Hadrian, and the two Antonines.

The most successful of the Tartar princes assumed the military command, to which he was entitled by the superiority either of merit or of power. He was raised to the throne by the acclamations of his equals; and the title of Khan expresses, in the language of the North of Asia, the full extent of the regal dignity. The right of hereditary succession was long confined to the blood of the founder of the monarchy; and at this moment all the Khans, who reign from Crimea to the wall of China, are the lineal descendants of the renowned Zingis.

[The] operation of the wisest laws is imperfect and precarious. They seldom inspire virtue, they cannot always restrain vice.

The nations, and the sects, of the Roman world, admitted with equal credulity, and similar abhorrence, the reality of that infernal art [witchcraft], which was able to control the eternal order of the planets, and the voluntary operations of the human mind. . . . They believed, with the wildest inconsistency, that this preternatural dominion of the air, of earth, and of hell, was exercised, from the vilest motives of malice or gain, by some wrinkled hags and itinerant sorcerers, who passed their obscure lives in penury and contempt.