Tao Te Ching Chapter 69
There is the maxim of military strategists;
I dare not be the first to invade, but rather be the invaded.
Dare not press forward an inch, but rather retreat a foot.
That is, to march without formations,
To roll up the sleeves,
To charge not in frontal attacks,
To arm without weapons.
There is no greater catastrophe than to underestimate the enemy.
To underestimate the enemy might entail the loss of my treasures.
Therefore when two equally matched armies meet,
It is the man of sorrow who wins.