reversion from one to the other at the extremes. Master Sun says, “Do not stop
an army on its way home. A surrounded army must be given a way out. Do not
press a desperate enemy.” The I Ching says, “The sovereign uses three chasers,
letting the game ahead escape,” and “if you are too adamant, action is unlucky,
even if you are right.”
The eighth chapter of The Art of War is devoted to adaptation, already seen to
be one of the cornerstones of the warrior’s art. Master Sun says, “If generals do
not know how to adapt advantageously, even if they know the lay of the land
they cannot take advantage of it.” The I Ching says, “Persist too intensely at
what is currently beyond your depth, and your fidelity to that course will bring
misfortune, no gain.”
Adaptability naturally depends on readiness, another persistent theme of The
Art of War. Master Sun says, “The rule of military operations is not to count on
opponents not coming, but to rely on having ways of dealing with them; not to
count on opponents not attacking, but to rely on having what cannot be
attacked.” The I Ching says, “If you take on too much without a solid
foundation, you will eventually be drained, leaving you with embarrassment and
bad luck.”
In The Art of War, readiness does not just mean material preparedness;
without a suitable mental state, sheer physical power is not enough to guarantee
victory. Master Sun here defines the psychological dimensions of the victorious
leader indirectly, by enumerating five dangers—to be too willing to die, too
eager to live, too quick to anger, too puritanical, or too sentimental. Any one of
these excesses, he affirms, create vulnerabilities that can easily be exploited by
canny opponents. The I Ching says, “When waiting on the fringes of a situation,
before the appropriate time to go into action has arrived, be steady and avoid
giving in to impulse—then you won’t go wrong.”
The ninth chapter deals with maneuvering armies. Again Master Sun deals
with all three aspects of the warrior’s art—the physical, social, and
psychological. In concrete physical terms, he begins by recommending certain
obvious types of terrain that enhance the odds of victory: high ground, upstream,
the sunny side of hills, regions with plenty of resources. Referring to all three
dimensions, he then describes ways of interpreting enemy movements.
Although Master Sun never dismisses the weight of sheer numbers or material
might, here as elsewhere there is the strong suggestion that social and
psychological factors can overcome the sort of power that can be physically
quantified: “In military matters it is not necessarily beneficial to have more, only
to avoid acting aggressively; it is enough to consolidate your power, assess
opponents, and win people, that is all.” The I Ching says, “When you have