As water shapes its flow in accordance with the ground, so an army manages its victory in accordance with the situation of the enemy.
Sun TzuYou 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 TzuThus those skilled in war subdue the enemy's army without battle .... They conquer by strategy.
Sun TzuIt is the rule in war, if ten times the enemy's strength, surround them; if five times, attack them; if double, be able to divide them; if equal, engage them; if fewer, defend against them; if weaker, be able to avoid them.
Sun Tzu