“Although the prince will never make any decision hastily, he will never be more hesitant or more circumspect than in starting a war; other actions have their different disadvantages, but war always brings about the wreck of everything that is good, and the tide of war overflows with everything that is worst; what is more, there is no evil that persists so stubbornly. War breeds war; from a small war a greater is born, from one, two; a war that begins as a game becomes bloody and serious; the plague of war, breaking out in one place, infects neighbours too and, indeed, even those far from the scene.
[. . .]
Certain arts, such as astrology and what is called alchemy, were banned by law because they were too close to fraud and were generally managed by trickery, even if it were possible for a man to practise them honestly. This would be far more justifiable in the case of wars, even if some of them might be just — although with the world in its present state, I am not sure that any of that kind could be found, that is, wars not caused by ambition, anger, arrogance, lust, or greed. It often happens that the leaders of men, more extravagant than their private resources will allow, will take a chance to stir up war in order to boost their own finances, even by pillaging their own people. 'This is sometimes done by princes in collusion with one another, on some trumped-up pretext, in order to weaken the people and to strengthen their own position at the expense of the state. For these reasons the good Christian prince must be suspicious of all wars, however just.
[. . .]
The godly and merciful prince will also be influenced by seeing that the greatest part of all the great evils which every war entails falls on people unconnected with the war, who least deserve to suffer these calamities. When the prince has made his calculations and reckoned up the total of all these woes (if indeed they could ever be reckoned up), then let him say to himself: ‘Shall I alone be the cause of so much woe? Shall so much human blood, so many widows, so many grief-stricken households, so many childless old people, so many made undeservedly poor, the total ruin of morality, law, and religion: shall all this be laid at
my door? Must I atone for all this before Christ?”
―
Erasmus,
The Education of a Christian Prince with the Panegyric for Archduke Philip of Austria