The story Mr. Know All is a tale about Prejudice , Racism and Stereotyping.
A British passenger finds himself forced to share a cabin on an ocean liner with the loud, opinionated, supremely self-confident gem dealer Max Kelada . Kelada soon dominates all the onboard social gatherings, much to the annoyance of his fellow passengers, who take to calling him "Mr. Know-All" behind his back because of his insistence that he is an expert on all subjects.
One night, he remarks on the fine quality of the pearl necklace worn by the pretty Mrs. Ramsay , who has rejoined her husband after a year's separation caused by his work. Mr. Ramsay bets him that the pearls are fake; Kelada swiftly accepts the wager, despite Mrs. Ramsay's attempt to call it off. While examining the pearls, Kelada observes that the woman is very upset. He then admits that he was wrong and pays Mr. Ramsay. The readers can infer that despite himself, Kelada feels sorry for Mrs. Ramsay, and spares her embarrassment at the cost of his own public ridicule.
Seeing this behavior, the British narrator begins to warm to his cabin mate.