"The art of using troops is this: ......When ten to the enemy's one, surround him; ......When five times his strength, attack him; ......If double his strength, divide him; ......If equally matched you may engage him; ......If weaker numerically, be capable of withdrawing; ......And if in all respects unequal, be capable of eluding him, ..........for a small force is but booty for one more powerful."