“A clever general, therefore, avoids an army when its spirit is keen, but attacks it when it is sluggish and inclined to return. This is the art of studying moods.”

“You can be sure of succeeding in your attacks if you only attack places which are undefended.You can ensure the safety of your defence if you only hold positions that cannot be attacked.”

“Sun Tzu said: In the operations of war, where there are in the field a thousand swift chariots, as many heavy chariots, and a hundred thousand mail-clad soldiers, with provisions enough to carry them a thousand Li, the expenditure at home and at the front, including entertainment of guests, small items such as glue and paint, and sums spent on chariots and armour, will reach the total of a thousand ounces of silver per day. Such is the cost of raising an army of 100,000 men.”

“The quality of decision is like the well-timed swoop of a falcon which enables it to strike and destroy its victim.”

“For should the enemy strengthen his van, he will weaken his rear; should he strengthen his rear, he will weaken his van; should he strengthen his left, he will weaken his right; should he strengthen his right, he will weaken his left. If he sends reinforcements everywhere, he will everywhere be weak.”

“Knowledge of the enemy's dispositions can only be obtained from other men.”

“These are: (1) the Moral Law; (2) Heaven; (3) Earth; (4) the Commander; (5) method and discipline.”