CODEXCard 2 of 9 · Art of War, Core Nine
Know your enemy and know yourself (Know the Enemy, Know Yourself)
Half-knowledge is half-defeat.
Know your enemy and know yourself is perhaps the most quoted line from The Art of War. Sun Tzu set out three cases. Know both sides and you can face many battles without fear. Know only yourself and you will win about as often as you lose. Know neither and you will be in danger every time.
Behind the line is a simple point about information. Strategy depends on comparing strengths, weaknesses, resources and intentions. If you misjudge your own abilities you will take on fights you cannot handle. If you misjudge the other side you will be surprised by their moves. Sun Tzu also stressed gathering information before acting, including through scouts and spies.
The trap is turning study into a reason never to move. Knowledge has diminishing returns, and waiting for complete information means the moment may pass. Sun Tzu valued speed as much as insight. Gather enough to make a sound judgment, then act and keep learning as events unfold.
Self-knowledge is the half most people neglect. An honest inventory of your limits, habits and emotional triggers is often more useful than any amount of research on a rival.
Example
Before buying a used car, a woman checks the typical price for that model, how long the listing has been up, and whether the seller seems in a hurry. She also admits to herself that she hates haggling and sets a firm maximum in advance. She ends up paying a fair price without getting talked upward.
Try it this week
Before your next negotiation, write three things you know about the other side's needs and one weakness of your own.
From Art of War, Core Nine (Sun Tzu · 500 BC).
