What does it mean to be a gentleman?

"Gentleman" refers to a person with ambition, integrity and achievement; "When" means should, should; "Towards the blue sea and dusk at Cangwu" refers to being in the blue sea in the morning and arriving at Cangwu Mountain in the evening. Generally speaking, the whole sentence is figurative, taking the gentleman's "morning in the blue sea and night in Cangwu Mountain" as a metaphor. Aspiring people should have the heroism of "reading thousands of books, taking Wan Li Road" and "being at home".

"A gentleman dies facing the blue sea" comes from the story of Xu Xiake's childhood.

The source of this sentence:

From Xu Xiake's friend Chen's Epitaph of Xu Xiake, the original text is "The husband faces the blue sea, and the sky is dark, so it is limited to a corner", which means that a gentleman should swim in the blue sea in the morning and in the sky at night. How can he tie himself to one place? From this, future generations can express that an ambitious person should travel around the world with a broad mind, rather than just seeing the present.

Xu Xiake (1586— 164 1) is a native of Jiangyin, Jiangsu. He was a famous geographer, traveler, explorer and writer in the Ming Dynasty, and was called "the Wonder of the Ages".