《战国策·赵三·赵惠文王三十年》
现在方圆千丈的大城、户口上万的大邑相互对峙，如果想用三万的兵力去包围千丈的大城，恐怕连城的一角都围不住，至于进行野战就更加不够了，你能拿这点兵力去干什么呢? 
今千丈之城，万家之邑相望也，而索以三万之众，围千丈之城，不存其一角，而野战不足用也，君将以此何之？ 
Now, large cities with a circumference of a thousand zhang and large towns with a population of tens of thousands are facing each other. If you want to use 30,000 troops to surround a large city of a thousand zhang, I am afraid that you will not even be able to surround a corner of the city. As for fighting in the field, it will not be enough. What can you do with this amount of troops?