Various stratagems had been devised to conceal the withdrawals from the Ottoman Army.
To penetrate this shield, the person has first to bring to the surface his psychological stratagems by identifying with them.
It is not strictly confined to warlike stratagems, but includes also examples of wisdom, courage and cunning drawn from civil and political life.
When the Parthian War (162-5) broke out, Polyaenus, too old to share in the campaign, dedicated to the emperors Marcus Aurelius and Lucius Verus a work, still extant, called Strategica or Strategemata, a historical collection of stratagems and maxims of strategy written in Greek and strung together in the form of anecdotes.
The stratagems and disguises by which with the help of a few faithful friends he slew the suitors are described at length in the Odyssey.