Excerpt from <span class="chinese-post-title">述郭雲深先生言</span> Report of Guō Yúnshēn Sayings in <span class="chinese-post-title">拳意述真</span> Boxing Concepts Explained Authentically

九則

拳術之道。要自己煅練身體。以却病延年。無大難法。若與人相較。則非易事。第一存心謹慎。要知己知彼。不可驕矜。驕矜必敗。
(...)
所宜知者一覿面先察其人。精神是否虛靈氣。質是否雄厚。身軀是否活潑。再察其言論。或謙或矜。其所言與其人之神氣。形體動作。是否相符。觀此三者。彼之藝能。

郭雲深

"It is the way of boxing arts that you should first train your body in order to prevent disease and prolong life. In this there is no great difficulty, but competing with opponents is not an easy matter. The first thing to keep carefully in mind is that you should know both self and opponent. You must not be arrogant, for with arrogance you will surely lose.
(...)
Therefore you should know when first meeting your opponent to begin by examining him. Is his spirit nimble or no? Is his energy abundant or no? Is his body lively or no? Then examine his speech – modest or arrogant? Do his [1] speech, [2] spirit and energy, and [3] body movements all tally with each other? Observing these three things, you will have a general idea of his skills and abilities."

Excerpt from the translation by Paul Brennan, to be found in the Brennan Translation blog.