What are the key ideas in Henry James' Daisy Miller?

A key idea in Daisy Miller is culture clash. As a free-spirited American from New York, Daisy finds European class distinctions difficult to comprehend, as she does the restrictions on women—"ladies"—in Europe. She goes walking and to the Coliseum with Giovanelli, an Italian, because it seems ridiculous to her that she should shun the man just because he is Italian. She also resists the idea that people should be able to dictate to her who she can and cannot see. She doesn't understand that going around—especially alone—with an Italian is the equivalent in her "set" of going around with a black man in the American South at the time. She doesn't understand why this means she must be "cut" by Mrs. Walker.

Another key theme of the novella is innocence destroyed. Daisy represents innocence: she is naïve about European culture and about how easy it is to perish in Europe. She lets romantic ideas of seeing the Coliseum in the moonlight overtake her reason. She dismisses the idea that she could catch malaria doing this, just as she dismisses the dangers of going around with Giovanelli. In the end, her innocence destroys her, both socially and physically.

There two main themes of "Daisy Miller" by Henry James are that of the role of women and of the relationship between Europe and America.

the first idea found is the notion of American "innocence" versus European sophistication. The Europeans and long term expatriates of the novel have a very sophisticated code of manners, emphasizing restraint and propriety. The Americans are seen as naive, open and spontaneous. This raises a question of which is morally better.

The role of women is addressed in Daisy's unconventional behaviour such as walking unchaperoned and flirting. The main question of sexual morality is whether Daisy's apparent impropriety, because it is innocent, is actually in truth sinful or immoral compared to the surface restraint of the Europeans or actually more pure because it is not so self-aware.

How does Henry James depict changes in American behavior in Daisy Miller?

Henry James uses characterization to explore changes in the behavior and attitudes of Americans abroad. The differences of generation are highly evident, with the youngest people exhibiting behaviors that vary sharply from those of the oldest characters. In addition, the family status of the young people is significant. People who have acquired their wealth recently are likely to behave differently than those whose family wealth is well established. A third key distinction is the length of time that the characters have spent in Europe. James implies that the Americans who have become permanent expatriates have thoroughly incorporated European ways of life, but they've also become detached from social changes happening back home.

Daisy Miller herself is the most representative of the young, newly wealthy American who has recently arrived in Europe. She sees no reason to adapt her conduct to conform to the European standards that others seek to impose on her.

Frederick Winterbourne is close enough to Daisy’s age to be a potential suitor. However, he is more aligned with the older generation because he and other members of his wealthy family have been living in Switzerland for a long time. Winterbourne’s embrace of European social conventions causes him to disapprove of Daisy’s behavior.

Mrs. Walker is an older woman who has served as the social center of expatriate life in Rome. Her established wealth and status support her adopting a judgmental role regarding the increasing numbers of Americans who are visiting Italy.