Sun Tzu said:
In times of old
Those skilled in warfare
First made themselves impossible to defeat,
Then waited for an opportunity to defeat the enemy.
Being impossible to defeat lies with oneself.
The opportunity to defeat the enemy lies with the enemy.
That is why
Those skilled in warfare
Can make themselves impossible to defeat,
But cannot make certain of defeating the enemy.
Thus it is said:
You may know how to achieve victory
Yet be unable to do so.
Being impossible to defeat comes with the defense.
The chance of victory comes with the attack.
One mounts a defense when one's strength is insufficient.
One attacks when one's strength is more than enough.
Those who are skilled at defense
Conceal themselves below.
Those who are skilled at attack
Strike from above.
Thus they are able to both protect themselves
And gain complete victory.
To discern a victory,
When it is known to all,
Is no mark of true skill.
To win a battle,
And be praised for it by all,
Is no mark of true skill.
To lift a strand of hair
Is no mark of great strength;
To see the sun and the moon
Is no mark of sharp sight;
To hear the clap of thunder
Is no mark of an acute hearing.
The ancient masters of warfare gained victory
When victory had been made easy to gain.
So the battles they won
Brought them neither reputation for wisdom
Nor merit for courage.
The victories of the master of warfare are without error.
They are without error so they are inevitable.
They are won over an already defeated enemy.
Those skilled in warfare
Take up a position which cannot be defeated
And miss no opportunity to defeat the enemy.
That is why
The victorious army first seeks victory,
Then it begins to fights.
The vanquished army first fights
Then it begins to seek victory.
Those skilled in warfare
Follow Tao and abide by military procedures.
So can bring about victory or defeat.
These are the methods in fighting a war:
One: taking measurements.
Two: making estimates.
Three: making calculations.
Four: weighing the chances.
Five: securing victory.
Measurements follow from the terrain.
Estimates follow from the measurements.
Calculations follow from the estimates.
The weighing of chances follows from calculations.
Victory follows from the weighing of chances.
A victorious army is like a ton pitted against an ounce.
A vanquished army is like an ounce pitted against a ton.
When the victorious are sent into battle
They are like flood water pouring into a gorge.
So much
On the subject of formation.