* The dangers of judging by appearances: The story highlights how easily we can be misled by initial impressions. The reader, like the police, initially suspects the innocent Charles McCarthy based on his rough appearance and the fact that he was quarrelling with his father.
* The importance of seeking truth and justice: The story emphasizes the need to look beyond superficial judgments and delve into the truth, no matter how uncomfortable or inconvenient it may be. Holmes's methodical investigation unveils the real culprit, showing that justice cannot be achieved through assumptions.
* The consequences of greed and selfishness: The story demonstrates how unchecked greed and selfishness can lead to devastating consequences. The murder, driven by a desire for inheritance, underscores the destructive power of avarice.
* The fragility of human relationships: The story explores the complex and often strained relationships between fathers and sons. The tension between Charles and his father, culminating in tragedy, shows the vulnerability of family bonds.
* The importance of critical thinking and observation: Holmes's success in solving the mystery lies in his ability to meticulously observe details and analyze evidence. He encourages the reader to think critically and not accept appearances at face value.
Ultimately, the Boscombe Valley Mystery serves as a reminder that appearances can be deceiving and that true justice requires careful investigation and a willingness to question assumptions. It underscores the importance of seeking truth and justice, even when it's uncomfortable, and the consequences of allowing greed and selfishness to cloud our judgment.