Having collected an army and concentrated his forces, he must blend
and harmonise the different elements thereof before pitching his camp.
Ts‘ao Kung takes 和 as referring to the 和門 or main gate of the
military camp. This, Tu Mu tells us, was formed with a couple of
flags hung across. [Cf. _Chou Li_, ch. xxvii. fol. 31 of the
Imperial edition: 直旌門.] 交和 would then mean “setting up his 和門
opposite that of the enemy.” But Chia Lin’s explanation, which has
been adopted above, is on the whole simpler and better. Chang Yü,
while following Ts‘ao Kung, adds that the words may also be taken
to mean “the establishment of harmony and confidence between the
higher and lower ranks before venturing into the field;” and he
quotes a saying of Wu Tzŭ (chap. 1 _ad init._): “Without harmony
in the State, no military expedition can be undertaken; without
harmony in the army, no battle array can be formed.” In the
historical romance 東周列國, chap. 75, Sun Tzŭ himself is
represented as saying to 伍員 Wu Yüan: 大凡行兵之法先除內患然後方可外征
“As a general rule, those who are waging war should get rid of all
domestic troubles before proceeding to attack the external foe.” 舍
is defined as 止. It here conveys the notion of encamping after
having taken the field.