Wise generals through the ages have learned to begin by examining the means they have at hand and then to develop their strategy out of those tools. They always think first of the givens—the makeup of their own army and of the enemy’s, their respective proportions of cavalry and infantry, the terrain, their troops’ morale, the weather. That would give them the foundation not only for their plan of attack but also for the ends they wanted to achieve in a particular encounter. Instead of being locked in to a way of fighting, they constantly adjust their ends to their means. The next time you launch a campaign, try an experiment: do not think about either your solid goals or your wishful dreams, and do not plan out your strategy on paper. Instead think deeply about what you have—the tools and materials you will be working with. Ground yourself not in dreams and plans but in reality: think of your own skills, any political advantage you might have, the morale of your troops, how creatively you can use the means at your disposal. Then, out of that process, let your plans and goals blossom. Not only will your strategies be more realistic, they will be more inventive and forceful. Dreaming first of what you want and then trying to find the means to reach it is a recipe for exhaustion, waste, and defeat.

Daily Law: Constantly balance ends and means: you might have the best plan to achieve a certain end, but unless you have the means to accomplish it, your plan is worthless.

The 33 Strategies of War

, Strategy 8: Pick Your Battles Carefully—The Perfect-Economy Strategy.