As the ancients said, know yourself and your enemy.
正如古人所说，了解自己和敌人。
该句使用了简单的祈使结构表达古人观点。
"Sometimes, while problems are complex, the answers are quite simple."
"The wise seek solutions within themselves; the foolish seek them from others."
"Learn to retreat when facing difficulties at the right time."
"Consider multiple perspectives and anticipate dangers in advance."
"Conquering with a smile is better than attacking with a sword."