Final answer:
Stevenson creates interest in the reader with mention of still undiscovered treasure and the arrival of a mysterious character in the narrator's life.
Step-by-step explanation:
The best explanation for Stevenson's reason for beginning the chapter with this paragraph is that he creates interest in the reader with mention of still undiscovered treasure and the arrival of a mysterious character in the narrator's life. By mentioning the treasure and the arrival of the brown old seaman with the sabre cut, Stevenson hooks the reader's attention and creates suspense, making them want to continue reading to find out what happens next.
Learn more about Stevenson's reason for beginning the chapter with this paragraph