VARIATION IN TACTICS

 1. Sun Tzu said: In war, the general receives
  his commands from the sovereign, collects his army
  and concentrates his forces

 2. When in difficult country, do not encamp. In country
  where high roads intersect, join hands with your allies. 
  Do not linger in dangerously isolated positions. 
  In hemmed-in situations, you must resort to stratagem. 
  In desperate position, you must fight.

 3. There are roads which must not be followed,
  armies which must be not attacked, towns which must
  be besieged, positions which must not be contested,
  commands of the sovereign which must not be obeyed.

 4. The general who thoroughly understands the advantages
  that accompany variation of tactics knows how to handle
  his troops.

 5. The general who does not understand these, may be well
  acquainted with the configuration of the country, yet he
  will not be able to turn his knowledge to practical account.