That it is the highest Quality of a Captain to be able to forestall the designs of his Adversary.

It was a saying of Epaminondas the Theban that nothing was so useful and necessary for a commander as to be able to see through the intentions and designs of his adversary. And because it is hard to come at this knowledge directly, the more credit is due to him who reaches it by conjecture. Yet sometimes it is easier to fathom an enemy's designs than to construe his actions; and not so much those actions which are done at a distance from us, as those done in our presence and under our very eyes. For instance, it has often happened that when a battle has lasted till nightfall, the winner has believed himself the loser, and the loser has believed himself the winner and that this mistake has led him who made it to follow a course hurtful to himself. It was from a mistake of this sort, that Brutus and Cassius lost the battle of Philippi. For though Brutus was victorious with his wing of the army Cassius, whose wing was beaten, believed the entire army to be defeated, and under this belief gave way to despair and slew himself. So too, in our own days, in the battle fought by Francis, king of France, with the Swiss at Santa Cecilia in Lombardy, when night fell, those of the Swiss who remained unbroken, not knowing that the rest had been routed and slain, thought they had the victory; and so believing would not retreat, but, remaining on the field, renewed the combat the following morning to their great disadvantage. Nor were they the only sufferers from their mistake, since the armies of the Pope and of Spain were also misled by it, and well-nigh brought to destruction. For on the false report of a victory they crossed the Po, and had they only advanced a little further must have been made prisoners by the victorious French.

An instance is recorded of a like mistake having been made in the camps both of the Romans and of the Equians. For the Consul Sempronius being in command against the Equians, and giving the enemy battle, the engagement lasted with varying success till nightfall, when as both armies had suffered what was almost a defeat, neither returned to their camp, but each drew off to the neighboring hills where they thought they would be safer. The Romans separated into two divisions, one of which with the consul, the other with the centurion Tempanius by whose valour the army had that day been saved from utter rout. At daybreak the consul, without waiting for further tidings of the enemy, made straight for Rome; and the Equians, in like manner, withdrew to their own country. For as each supposed the other to be victorious, neither thought much of leaving their camp to be plundered by the enemy. It so chanced, however, that Tempanius, who was himself retreating with the second division of the Roman army, fell in with certain wounded Equians, from whom he learned that their commanders had fled, abandoning their camp; on hearing which, he at once returned to the Roman camp and secured it, and then, after sacking the camp of the Equians, went back victorious to Rome. His success, as we see, turned entirely on his being the first to be informed of the enemy's condition. And here we are to note that it may often happen that both the one and the other of two opposed armies shall fall into the same disorder, and be reduced to the same straits; in which case, that which soonest detects the other's distress is sure to come off best.

I shall give an instance of this which occurred recently in our own country. In the year 1498, when the Florentines had a great army in the territory of Pisa and had closely invested the town, the Venetians, who had undertaken its protection, seeing no other way to save it, resolved to make a diversion in its favour by attacking the territories of the Florentines in another quarter. Wherefore, having assembled a strong force, they entered Tuscany by the Val di Lamona, and seizing on the village of Marradi, besieged the stronghold of Castiglione which stands on the height above it. Getting word of this, the Florentines sought to relieve Marradi, without weakening the army which lay round Pisa. They accordingly raised a new levy of foot-soldiers, and equipped a fresh squadron of horse, which they despatched to Marradi under the joint command of Jacopo IV. d'Appiano, lord of Piombino, and Count Rinuccio of Marciano. These troops taking up their position on the hill above Marradi, the Venetians withdrew from the investment of Castiglione and lodged themselves in the village. But when the two armies had confronted one another for several days, both began to suffer sorely from want of victuals and other necessaries, and neither of them daring to attack the other, or knowing to what extremities the other was reduced, both simultaneously resolved to strike their camps the following morning, and to retreat, the Venetians towards Berzighella and Faenza, the Florentines towards Casaglia and the Mugello. But at daybreak, when both armies had begun to remove their baggage, it so happened that an old woman, whose years and poverty permitted her to pass unnoticed, leaving the village of Marradi, came to the Florentine camp, where were certain of her kinsfolk whom she desired to visit. Learning from her that the Venetians were in retreat, the Florentine commanders took courage, and changing their plan, went in pursuit of the enemy as though they had dislodged them, sending word to Florence that they had repulsed the Venetians and gained a victory. But in truth this victory was wholly due to their having notice of the enemy's movements before the latter had notice of theirs. For had that notice been given to the Venetians first, it would have wrought against us the same results as it actually wrought for us.