"Thus, if his people appear, yet we are formless, then we will be concentrated while the enemy will be divided. We, being concentrated, serve as one, and the enemy, being divided, serves as ten. If, by means of ten units, we attack one of his - then we are many and the enemy is few. And if we, by means of our many, can strike his few, then the place by which we join in battle will be reduced."
- Sun Tzu

In this critical passage, Sun Tzu ties together the principle of deception with the factor of  physical size, which, as we discussed in Book 3, is an important element in achieving victory. For Sun Tzu, the absolute size of an army is irrelevant; however, the relative size of unit fighting another unit is very important. The goal is to outnumber the opponent at the point where he is weakest.

Achieving this, for Sun Tzu, relies on deception - on being "formless" (wu xing). Being formless, the enemy does not know where to attack us. This allows our army to act as a mysterious, yet well-coordinated unit since we do not have to worry about defending ourselves.

Being formless also serves to divide the enemy, because, not knowing where to defend, it provokes the enemy to spread out his defenses. Against a spread out defense, we can concentrate our forces to attack a single area of vulnerability - i.e. where his forces are fewest and we outnumber him. This is what Sun Tzu means when he says, "[T]he place by which we join in battle will be reduced."

In your own life, size is also a critical factor. However, what is important in achieving success is not absolute size - for example, being completely bigger than your competitor - but relative size - that is, being bigger than your competitor at critical weak points. A small tech company will not be able to compete with a company like Google on a grand scale, but neither does it have to. It simply needs to find an underserved market that a company like Google doesn't have the concentrated resources to dominate in.

Likewise, if you are competing with someone at work for a new position, it is not necessary to have all the advantages over this person - connections, education, experience, etc. What matters is that you understand critical aspects of the position where this person is weak and that you can outshine him or her in. That's what you have to focus on.

And if you've kept your intentions effectively concealed, then your competitor won't realize that you're attacking a critical point until it is too late.

"Therefore, if we want to do battle, even if the enemy has high ramparts and deep moats, he cannot but give us battle, because we attack that which he must rescue. If we do not want to do battle, even if we draw a line on the ground and defend it, the enemy cannot give us battle, because we outsmart him."
- Sun Tzu

This passage reinforces a concept that Sun Tzu promotes throughout The Art of War: that having the advantage over the enemy in battle is not physical, but psychological. It's not a matter of being bigger, stronger, or more powerful - it is a matter of controlling the enemy's perception. This requires understanding two things: what the enemy values and what will confuse him.

Threatening what the enemy values forces the enemy to be on the defensive - to "give us battle." This is achieved through intelligence. Confusing the enemy prevents the enemy from attacking us, even if our defense is not strongly guarded. This is done through showing the enemy potential harm, trouble, or doubt. (As Sun Tzu tells us: "To be able to cause the enemy not to come means causing him trouble.")

In life, you must take this concept to heart. When dealing with competitors, gaining an advantage is not a matter of resources or power. Rather, it is a matter of controlling the psychology of your competitors. What do they value? What will confuse them? How do they view you as competition?

If you find yourself having to confront a competitor - for example, in the news or in front of other people - you want to make sure to confront them with something they must respond to, something that they value (their reputation, for example).

If you find yourself having to defend against a competitor, you want to make sure to do something that confuses them, that puts them on-guard, that makes them doubt their positioning or intentions.

Don't focus simply on the physical aspects of your competition - focus on their psychology. That is what ultimately controls their responses, and gives you an opportunity to swoop in.

"One who advances yet cannot be resisted rushes to [the enemy's] weak [empty] points. One who withdraws yet cannot be pursued speeds away so he cannot be reached."
- Sun Tzu

This passage goes along with the two before it. In the first Book, we talked about the two aspects of deception: concealment and surprise. Concealment protects the army and sets it up for surprising the enemy. And surprise is what ultimately throws the enemy off-guard, setting him up for defeat.

In the previous passage, Sun Tzu talks about being formless and soundless. These qualities are essential to concealing the army's positioning. In this passage, Sun Tzu is talking about speed - rushing to the enemy's weak points and withdrawing before the enemy can even respond. Speed, then, is the critical factor for surprising the enemy.

To recap, Sun Tzu's strategy here is twofold. First, the army must set itself up, unconcealed to the enemy. It does this by taking over grounds that the enemy does not occupy or care to notice. As the army builds its positioning, it maintains its formlessness through deceptive actions - spreading misinformation, appearing smaller or less concentrated, etc.

Second, when the moment is right to attack, the army moves with incredible speed, attacking where the enemy is unguarded or weak, thereby catching the enemy off-guard. After it has completed its attack, it then withdraws before the enemy can regroup. The general repeats this strategy until the enemy essentially falls apart.

In your own life, you need the two critical factors as well: formlessness (wu xing) and speed (su). Napoleon has a famous quote: "Be slow in deliberation and quick in execution." I would modify this quote slightly: "Be slow in deliberation, formless in preparation, and quick in execution." Once you've decided a path forward and it is protected, you must move very quickly once you see an opportunity.

The important thing is that what you "strike" does not need to be huge. Perhaps it is a new client, or a new connection, or an opportunity to build a relationship. Any advantage you can get is a step in the right direction. Whatever it is, you want to secure it as quickly as possible and rinse and repeat. This is how you build strength over time. 

"Therefore, against one skilled in attack, the enemy does not know where to defend. Against one skilled in defense, the enemy does not know where to attack. Subtle, subtle! To the point of formlessness. Mysterious, mysterious! To the point of soundlessness. Therefore, he is master of the enemy's fate."
- Sun Tzu

Although Sun Tzu is being dramatic for effect, there is an interesting use of metaphor to describe his point.

Vision, for Sun Tzu, is connected to being able to observe (and thus understand) one's positioning or situation. Being formless means that the enemy cannot accurately decipher one's position or situation. Thus, the enemy cannot determine one's weaknesses and strengths.

Likewise, hearing relates to the use of spies. Being soundless, then, means that the enemy's spies cannot report anything useful back to the enemy. Thus, the enemy cannot determine what one is planning to do. 

Without his eyes, the enemy doesn't know where to attack. Without his ears, the enemy doesn't know where to defend. This leaves the enemy effectively helpless, even if his army is bigger.

In life, you want to have the same effect. People should never know what you are capable of or what you are planning. This is the principle of concealment. Not knowing what you are capable of or what you're planning, they can't prepare against you. This allows you to keep yourself protected (people can't block you) as well as in a position to surprise them.

"One who marches a thousand li and is not troubled marches where the ground has no people. One who attacks and is certain to gain attacks [the enemy] where he is not guarded. One who guards and is certain to be strong guards himself where he cannot be attacked."
- Sun Tzu

In this passage, Sun Tzu outlines three key aspects of battle: movement (marching), attack, and defense. As you can see, Sun Tzu's primary concern is always with maintaining security and protection. This is, after all, the primary objective of the general - not to seek glory or wealth, but to keep the nation secure.

 Thus, in moving, the army must travel through unoccupied grounds. In attacking, the enemy must be unguarded. In guarding, one must occupy a place that deters the enemy from attacking you . Although these objectives seem like common-sense, Sun Tzu's point is that these must be top of mind for the general.

So in war, also in life. In a competitive situation, move to where your competitors are not. Take action on low-hanging fruit and other undefended territories. Secure a position where competitors will not want to compete with you - either because the barrier to entry is too high or because you are too highly skilled at defending that position for the enemy to take the risk.

The more you go through this process (moving to uncontested territory > attacking easy, unguarded targets > securing an unassailable position), the stronger you'll become and the more likely a) your competitors will not want to compete with you, or b) you'll more easily overcome the competition.

"Go out to where he does not hurry. Hurry to places he does not expect."
- Sun Tzu

This passage relates to the two aspects of deception mentioned in Book 1: concealment and surprise. For Sun Tzu, the army must take an indirect route to establish its position. Taking the indirect route means travelling through places that the enemy is not worried about, and thus does not hurry to. This is concealment. Then the army can catch the enemy off-guard by appearing where the enemy did not expect. This is surprise.

In life, this same principle is applicable. If you are in a competitive environment, you must resist the urge to build up your position in an obvious way. If you're aiming for a particular internal position at your work, for example, don't start by declaring your intention. The people around you (potential competitors) will start building obstacles in your path.

Rather, you may want to start building relationships with people close to that position. Or you may want to volunteer for tasks that other people may not want, but that can highlight your skills and abilities related to that position. Then, when the time comes to put your hat in the ring, you'll likely be top of mind.

"To be able to cause the enemy naturally to come means enticing him. To be able to cause the enemy not to come means causing him trouble. Therefore, if the enemy is at ease, you can trouble him; if he is full, you can starve him; if he is calm, you can stir him."
- Sun Tzu

For Sun Tzu, an army typically acts for one of two reasons: to gain an advantage or to avoid harm. One who is skilled at deception (remember Sun Tzu's famous line - "Warfare is the way of deception") can cause the enemy to move from his current position regardless of whether that position is strong or not. Entice the enemy with a compelling enough gain, and he will move. Show him a big enough harm, and he will avoid you.

Therefore, even if the enemy has arrived first to the battleground, the general can still move him out of his position. He can trouble him, starve him, stir him. He just needs to understand his psychology - what would compel him to seek advantage or avoid harm.

In life, this same principle is true. If you are competing for control over a situation and another party has arrived first, don't simply go on offense. Rather, try to move him or her out of this position by either enticing or deterring with some form of disadvantage.

For example, if you are competing for an internal job position, for which you know another colleague has already applied or expressed interest, your best move is not simply to show interest as well and show how you're more qualified than the other person.

Rather, you need to focus on finding a way to show that the position is not in the other person's best interest. Finding this, of course, depends on the person's psychology. Maybe it'll be long hours, or working with someone the other person hates (deterrence). Or maybe you can entice the person with a different opportunity somewhere else (enticement).

Or let's say you are competing for a potential client with someone else who has already been courting this client. Your first instinct is probably to demonstrate to the client how and why you are superior to the competition.

But for Sun Tzu, this would be the wrong move. Your first move should be to try to move the competitor away from the potential client. Perhaps this means enticing the competitor to a different client, or finding a way to demonstrate that the client would be a bigger headache than the competitor would like to deal with. Or perhaps it means clearly demonstrating to your competitor why you are a much better fit for the client than the competitor is.

In short, never start by competing for control. Always strive first to move any competition from his or her current position. As we saw in the last passage, it all starts with obtaining a strong position first - one where you are prepared, calm, at ease. Then you can start competing.

"In general, one who first occupies the battleground and awaits the enemy is at ease, while one who arrives after to the battleground and rushes to fight is troubled. Therefore, the skilled warrior sends soldiers, but does not send [them] to soldiers."
- Sun Tzu

The title of Book 6 (xū shí) can be translated in multiple ways. A more direct translation is "Emptiness and Fullness." But it can also translate to mean "weakness and strength" as well as "the false and the real." And an abstract level it can also mean "the real situation," that is, getting to the bottom of a situation. All of these meanings will come into play throughout this chapter as we deal with the dynamics of battle and competition.

Sun Tzu opens this chapter with a simple phenomenon to understand: that of arriving before another in a competition. The army who arrives first to battle is ready and prepared; therefore, they are at ease. The army who arrives second and thus must rush to battle is troubled.

For Sun Tzu, the place of battle is the first factor for which a general must account. An empty ground that an army occupies before the enemy arrives strengthens the army's positioning; an occupied ground that an army tries to occupy afterwards weakens the army's positioning. One's positioning is weak (xū) or strong (shí) depending on whether the ground is empty (xū) or occupied (shí).

Thus, the first rule of battle, for Sun Tzu, is to try to send soldiers to an empty battleground - not to an already occupied one. This ensures that the battle starts off on the right foot - with a ready, prepared mind, and not one that is troubled.

This same principle applies to any situation that involves struggle, conflict, or competition. The ground, of course, is a metaphor, representing the situation you are in. An empty situation means that no party has taken control of it yet; an occupied situation means that one person or another has taken control of it.

So, for example, let's say a coveted position opens up in the company you work for due to someone leaving. The earlier you know about the open position (i.e. before the competition does), the earlier you can prepare and try to occupy it. The later you know (after the competition), the more difficult the competition will be.

Or let's say you find out through your information channels that a client of yours is dissatisfied with a recent service from your team. The sooner you can prepare to meet with the client and address this issue, the easier it will be to win this client back over. The later you prepare, however, the bigger the chances that resentment will build up and the client will take his money elsewhere.

In general, if you are in a competitive situation, you want to try to take control of it before a competitor even knows what's going on. This gives you a huge advantage.

Of course, as we'll see later in this chapter, if you do arrive late, you can still achieve victory. But you'll have to apply more cleverness.

"In administering force, one's soldiers become like rolling logs and stones. The nature of logs and stones is to be still if secure, to move about if endangered, to stop if square, and to move if round. Thus, the force of skilled warriors is like round stones rolling from a thousand ​jen high mountain. Such is force."
- Sun Tzu

Book 5 is filled with many metaphors and similes, and this concluding passage gives us our final metaphor: logs and stones. This passage reiterates and reinforces the point made in the previous one.

For Sun Tzu, force comes from two critical factors: positioning and adaptability (which is another aspect of jie, or timing). Soldiers who are in a safe, secure position will be still and quiet. Soldiers in an unsafe, dangerous position will be agitated. Soldiers who are "square" - i.e. who are stubborn or rigid - will be hard to move or direct. But soldiers who are "round" - who "go with the flow" and adapt to whatever ground they're in - will be able to gain momentum and perform effectively.

The key, for Sun Tzu, is having a general who is able to calculate the right position (i.e. a high enough mountain) and the right moment to command his soldiers to strike (i.e. release his logs and stones).

In your own life, the same principles apply. The position from which you try to achieve your goals must give you the momentum you need to overcome obstacles, even if you make mistakes (which you inevitably will). The whole idea behind strategy is to make winning easier.

Such is the power of shih​.

"Therefore, the skilled warrior seeks [victory] through force, not through reproaching his soldiers. In this way, he is able to select soldiers and allow for force."
- Sun Tzu

For Sun Tzu, victory is achieved when the army is settled in a position of overwhelming power over the enemy. This position is what we may call a position of shih, or force. Achieving shih is not done through demanding more from one's soldiers, making them work harder and harder, but from a series of calculations in which the army has accumulated a number of key advantages over the enemy.

Thus, the general's focus is never, "How can I make my soldiers work harder to defeat the enemy?" - but rather, "What position must we occupy that will give us a huge advantage over the enemy?" Once the army is in this position, then the general need only select a few key soldiers and let the position itself do the majority of the work in defeating the enemy.

This is a key principle to remember in your own life. Success is not simply a matter of working hard. It is a matter of working hard at attaining a few key, yet hidden or unnoticed vantage points - a certain relationship with a powerful figure, a certain reputation for credibility in the marketplace, a certain position at work that gives you key information about the company.

It's from these key positions that you can take simple actions to increase your chances of success.