How we cite our quotes:
When his friends spoke of him, they usually said that he was at Geneva "studying." When his enemies spoke of him, they said—but, after all, he had no enemies; he was an extremely amiable fellow, and universally liked. (1.2)
This is one place where our coy friend the narrator comes out to play. What's the deal with these enemies? Do they exist or don't they? Our money's on the "virtuous" Mr. Winterbourne having something to hide.
"But don't they all do these things--the young girls in America?" Winterbourne inquired.
Mrs. Costello stared a moment. "I should like to see my granddaughters do them!" she declared grimly. This seemed to throw some light upon the matter, for Winterbourne remembered to have heard that his pretty cousins in New York were "tremendous flirts." (1.139-40)
Mrs. Costello can't stand Daisy's flirtatious ways, even though her own granddaughters have reputations to match. Also, we think she's probably sarcastic when she says she'd like to see her granddaughters in flirt mode. Either that, or she's even more perverse than we thought.
If, therefore, Miss Daisy Miller exceeded the liberal margin allowed to these young ladies, it was probable that anything might be expected of her. Winterbourne was impatient to see her again, and he was vexed with himself that, by instinct, he should not appreciate her justly. (1.140)
This time, Winterbourne is like a young Christina Aguilera: his body's saying yes, but his heart is saying no.