3.4

Chapter: Attack by Stratagem 3.4
< /br>
Translation:

The rule is, not to besiege walled cities if it can possibly be avoided. The preparation of mantlets, movable shelters, and various implements of war, will take up three whole months; and the piling up of mounds over against the walls will take three months more.

< /br>
Commentary

Laying siege to a strongly defended position is poor in many ways. It is likely to drag on for a long time. It is hard work and takes much resource. Your troops are exposed while theirs are hidden. The sheer cost of siege makes it a final option only.