In our day we have seen Italian independence won by appeals to the patriotism of the nation at large. This was impossible in Machiavelli’s time; nor, had it been otherwise, would his lips have been touched with the live coal of a Mazzini. He could only speak as a politician to politicians, and addressing himself as it were to a body of scientific experts, he designedly excludes all considerations of morality. His treatise appears antiquated in our day, when the national conscience is as easily manipulated as the conscience of the individual; in oligarchical ages it passed not unreasonably for a perfect manual of statecraft, and exercised great influence upon the statesmen of the sixteenth and seventeenth centuries. Frederick the Great assailed it vehemently in his youth, but lived to compliment it by what has been described as the sincerest form of flattery. In Frederick’s century, when public affairs actually were in the hands of a few able rulers, it was worth attacking and defending; in the present democratic age, when a statesman who squared his conduct by its maxims would soon find himself the object of popular odium, its interest, except as regards its weighty plea for a popular army, is mainly historical and psychological. There is an intimate connection between the _Prince_ and the seven books on the _Art of War_, written about 1520. In the _Prince_ Machiavelli insists particularly upon the part which the habit of relying upon treacherous and mutinous mercenaries, and the consequent decay of public spirit among the citizens, had had in bringing about the ruin of the Italian states. In the _Art of War_ he shows how the citizen army he recommends is to be organised and led in battles and sieges. His experience of military affairs as an eye-witness, as well as an administrator, had been considerable, and he is by no means to be slighted as a tactical writer; but the military art was on the eve of great changes, which rendered much of his wisdom obsolete.