On tactics:
“When it is time to advance, advance without hesitation. If you meet no obstacle continue to advance. Failing to advance when the time is right is a lost opportunity. Seizing the opportunity to advance, you will surely be the victor.”
Song of Advance, From The T’ai Chi Classics
-Yang Lu-ch’an, compiled in the 19th Century

The Tao of aggressive warfare:
“Strategic power is exercised in accord with the enemy’s movements. Changes stem from the confrontation between the two armies. Unorthodox and orthodox tactics are produced from the inexhaustible resources of the mind. Thus the greatest affairs are not discussed, and the employment of troops is not spoken about. Moreover, words that discuss ultimate affairs are not worth listening to. The employment of troops is not so definitive as to be visible; they come and go suddenly. Only someone who can exercise sole control, without being governed by other men, is a military weapon. Thus one who excels in warfare does not await the deployment of forces. Conquering the enemy means being victorious over the formless. The superior Warrior does not engage in battle. In military affairs nothing is more important than certain victory. In employing the army nothing is more important than obscurity and silence. In movement nothing is more important than the unexpected. In planning nothing is more important than not being knowable.”
From Six Secret Teachings, chapter 26
-T’ai Kung, circa 1045 BC Chou Dynasty

On battle:
“Warfare is a question of the strategic balance of power, combat is a matter of courage. The deployment of formations is a matter of skill. Employ what your men want, effect what they are capable of; abolish what they do not want and are incapable of. Do the opposite of this to the enemy.”
From The Szu-ma Fa –Szu-ma Jang-chu, circa 403 BC

The nature of the army:
“The army is established by deceit, moves for advantage, and changes through segmenting and uniting. Thus its speed is like the wind, its slowness like the forest, its invasion and plundering like a fire; unmoving, it is like the mountains. It is as difficult to know as the darkness; in movement it is like thunder. Further, it is the nature of the army to stress speed; to take advantage of the enemy’s absence; to employ unorthodox tactics; and to attack when they are not alert.”
From ThePing-fa –Sun Tzu, circa 512 BC

On tactics:
“Being unexpected and relying on suddenness are the means by which to conduct unfathomable warfare.”
From Military Methods –Sun Pin, circa 475 BC

On tactics:
“An enemy who comes forth to insult and taunt your forces without proper discipline can be destroyed. Attack them like flood water rushing through a valley, like lightning striking without respite, and throw their army into chaos.”
From The Wei Liao-tzu –Wei Liao, circa 385 BC

On being deliberate:
“Of the many harms that can beset an army, indecisiveness is unsurpassed. One who excels in warfare will not lose an advantage when he perceives it, nor be doubtful when he meets the moment. Thus the wise follow the time and do not lose an advantage; the skillful are decisive and have no doubts.”
From Six Secret Teachings, chapter 26
-T’ai Kung, circa 1045 BC

On coaching:
“If you are respectful, your Warriors will be satisfied. If you lead in person they will follow. When orders are annoying they will be ignored.”
From The Szu-ma Fa –Szu-ma Jang-chu, circa 403 BC

The importance of recognizing opportunity:
“If the enemy does not make an error in judgment, how can our army conquer them? In chess both opponents begin equal in strength. Should one make a mistake, truly no one can rescue him. For this reason, in both ancient and modern times, victory and defeat have proceeded from a single error, so how much more would this be the case with many mistakes?”
From Questions and Replies Between T’ang T’ai-tsung
and Li Wei-kung, circa 627 BC

On team unity:
“As for the Tao of the military, nothing surpasses unity. A unified army will be victorious; dissention in the army will bring defeat.”
From The Wei Liao-tzu –Wei Liao, circa 385 BC

On employing deception:
“Warfare is the Tao of deception. Thus although you are capable, display incapability to them. When committed to employing your forces, feign inactivity. When your objective is nearby, make it appear as if distant; when far away, create the illusion of being nearby. Deliberate tactical errors are the means by which to bait the enemy.”
From The Art of War –Sun Tzu, circa 512 BC

Unconcerned with the outcome:
“In combat, one should fight with maximum strength and attention. Unrelenting action in desperation will press the opponent under heavy psychological burden. Even if you lose, your opponent will then regard you as an honored loser. In a combat situation, many people make the mistake of thinking too much about winning and losing. You should allow none of these sentiments to invade your mind. You need only to act as circumstances demand.”
-Bruce Lee

Assessing an adversary:
“Mount a sudden strike on their doubts. Attack their haste. Force them to constrict their deployment. Launch a sudden strike against their order. Take advantage of their failure to avoid harm. Obstruct their strategy. Seize their thoughts. Capitalize on their fears. Observe their tactical variations, advance and retreat to probe the solidity of their defenses. Endanger them to observe their fears. Be tranquil to observe if they become lax. Move to observe if they have doubts. Mount a surprise attack and observe their discipline.”
From The Szu-ma Fa –Szu-ma Jang-chu, circa 403 BC

Properly assessing one’s strengths:
“One who cannot be victorious assumes a defensive posture; one who can be victorious attacks. In these circumstances by assuming a defensive posture, strength will be more than adequate, whereas in offensive actions it would be inadequate. Thus a General who properly assesses the army’s qualities will be able to preserve his Warriors and attain complete victory.”
From The Art of War –Sun Tzu