The Prince by Niccolo Machiavelli Chapter 24 Page 3

Philip of Macedon, not the father of Alexander the Great, but he who was vanquished by Titus Quintius, had no great State as compared with the strength of the Romans and Greeks who attacked him. Nevertheless, being a Prince of a warlike spirit, and skilful in gaining the good will of the people and in securing the fidelity of the nobles, he maintained himself for many years against his assailants, and in the end, though he lost some towns, succeeded in saving his Kingdom.

Let those Princes of ours, therefore, who, after holding them for a length of years, have lost their dominions, blame not Fortune but their own inertness. For never having reflected in tranquil times that there might come a change (and it is human nature when the sea is calm not to think of storms), when adversity overtook them, they thought not