t these imply five obvious and
generally advantageous lines of action, namely: "if a certain
road is short, it must be followed; if an army is isolated, it
must be attacked; if a town is in a parlous condition, it must be
besieged; if a position can be stormed, it must be attempted; and
if consistent with military operations, the ruler's commands must
be obeyed." But there are circumstances which sometimes forbid a
general to use these advantages. For instance, "a certain road
may be the shortest way for him, but if he knows that it abounds
in natural obstacles, or that the enemy has laid an ambush on it,
he will not follow that road. A hostile force may be open to
attack, but if he knows that it is hard-pressed and likely to
fight with desperation, he will refrain from striking," and so
on.]

7. Hence in the wise leader's plans, considerations of
advantage and of disadvantage will be blended together.

["Whether in an advantageous position or a disadvantageous
one," says Ts`ao Kung, "the opposite state should be always
present to your mind."]

8. If our expectation of advantage be tempered in this way,
we may succeed in accomplishing the essential part of our
schemes.

[Tu Mu says: "If we wish to wrest an advantage from the
enemy, we must not fix our minds on that alone, but allow for the
possibility of the enemy also doing some harm to us, and let this
enter as a factor into our calculations."]

9. If, on the other hand, in the midst of difficulties we
are always ready to seize an advantage, we may extricate
ourselves from misfortune.

[Tu Mu says: "If I wish to extricate myself from a
dangerous position, I must consider not only the enemy's ability
to injure me, but also my own ability to gain an advantage over
the enemy. If in my counsels these two considerations are
properly blended, I shall succeed in liberating myself.... For
instance; if I am surrounded by the enemy and only think of
effecting an escape, the nervelessness of my policy will incite
my adversary to pursue and crush me; it would be far better to
encourage my men to deliver a bold counter-attack, and use the
advantage thus gained to free myself from the enemy's toils."
See the story of Ts`ao Ts`ao, VII. ss. 35, note.]

10. Reduce the hostile chiefs by inflicting damage on them;

[Chia Lin enumerates several ways of inflicting this injury,
some of which would only occur to the Or