Simon Rosedale's character in Edith Wharton's novel The House of Mirth has a philosophical basis that is as easy to notice as it is to predict: He is determined to acquire both money AND status in the very fashionable early 1900's New York society.
Not enough with that, he is determined to take over the scene by maneuvering it with money, and with this, he expects to earn the respect that he lacks for being four undesirable characteristics for such an elitist set: For Rosedale is a) Jewish, b) Unknown, c) unsophisticated, d) not part of the Dutch matriarchal set.
Simon Rosedale knows from the get go that he is an undesirable. He even admits to it by proposing Lilly to marry him. Lily does not have the money, but she has the connections. He is rich (nouveau, as it were), and lacks what she has. Far from being a good marriage, Lilly refuses to marry him. That is how low even the one at the bottom of the social barrel would think of him.
Lily's rejection is so humiliating that, even though he does feel a bit of compassion when she hits rock bottom, he ensures that he rejects her when she wished to marry him in a desperate attempt to regain some power back. In the end, we realize that in such society money ends up being the order of the day. Regardless of his humble origins and lack of social connections, his power ends up becoming redefined by his financial power. It is the beginning of the new capitalist society of New York City, and Rosedale is its major representative.