The Young Musician, like most earlier Horatio Alger novels, features a teenaged boy who, due to circumstances beyond his control, must take on responsibilities appropriate to an adult man. Lacking resources apart from his own skills, character, and ingenuity, Philip Gray manages to succeed.
Like most Alger heroes, Philip Gray is an orphan. His mother, mentioned only in the past tense, is not part of the story and his father dies when Philip is nearly sixteen, leaving him almost completely without resources. However Philip is intelligent, witty, and mature beyond his years. Although he makes the mistake of trusting "Professor" Lorenzo Riccabocca, who turns out to be a swindler, he shows astoundingly good judgement in other respects. He instantly recognizes that Winuca is friendly and not a threat, and once he realizes Riccabocca is dishonest he is not deluded by him a second time.
Philip inspires trust and confidence from other honest people. Indeed, people tend to believe in his honesty and integrity unless they themselves lack honesty. When Riccabocca runs off with all the money from a concert, leaving Philip to pay the bills, most of the men who have been defrauded recognize Philip as a fellow victim, and the only man who insists on being repaid regardless of the cost to others is someone already known for his meanness and lack of regard for other people. Philip inspires the trust of others and is admired both for his playing skill and his humble candor, but his successes attract the attention of people like Squire Pope, Joe Tucker, and Lorenzo Riccabocca who plan to exploit him or steal from him.
Like most early Alger heroes, Philip sends off class signals that mark him as rightfully belonging to a more sophisticated socioeconomic group than the one he occupies at the start of the story when he is a penniless pauper and a ward of the village who is installed against his will in a poorhouse. Instinctively attracted to wholesome things (such as the temperance-based literary club for which he plays a benefit concert), and instinctively repulsed by dishonest things such as Riccabocca's tendency to inflate his accomplishments, Philip is scrupulously honest with everybody, including people who have behaved dishonestly toward him. He returns Riccabocca's portion of the money they earned, which Riccabocca stole. He insists on paying his debts.
This novel, like most early Alger novels, presents a very black-and-white morality. The antagonists have no redeeming qualities whatsoever and are consistently vile, but in different ways. Squire Pope is a selfish, pompous, self-absorbed man whose excessive pride inspires him to exceed his authority. Joe Tucker and his family are cheap, venial people who have no desire to improve their lot in life. They are lazy, dishonest, and not at all conscientious. Lorenzo Riccabocca is a con artist and a thief, and the rival fiddler Paul Beck is presented as an uninspired, mediocre musician who is eclipsed by the relatively inexperienced but impassioned young Philip. In fact, not one person in the novel who is a reasonable human being has a conflict with Philip even after the Riccabocca disaster wherein Philip owes money to a lot of people but has no way to repay it. The only people who oppose Philip or mistrust him are significantly flawed and defective human beings. This phenomenon, described in the late 1990s as the "Mary Sue" or "Gary Stu" effect, is characteristic of a hero or heroine who possesses few or no obvious faults.
One recurring motif in the novel is Philip's violin, which symbolizes his path to independence. Twice, people in authority propose that Philip be forced to sell his violin to pay off a debt. Cooler heads prevail in both cases, however the threat to Philip's livelihood increases the plot tension.
