You can ensure the success of your attacks if you only attack places that are undefended. You can ensure the safety of your defense if you only hold positions that cannot be attacked. Therefore, that general is skillful in attack whose opponent does not know what to defend; and he is skillful in defense whose opponent does not know what to attack.
Sun TzuWhen you do battle, even if you are winning, if you continue for a long time it will dull your forces and blunt you edge...If you keep your armies out in the field for a long time, your supplies will be insufficient. Transportation of provisions itself consumes 20 times the amount transported.
Sun TzuThose who excel in war first cultivate their own humanity and and maintain their laws and institutions. By these means they make their governments invincible.
Sun TzuBirds rising in flight is a sign that the enemy is lying in ambush; when the wild animals are startled and flee he is trying to take you unaware.
Sun Tzu