Scott Fitzgerald, we learn that every character, except Nick and George, uses wealth as a means of happiness, which in turn, gets in the way of their own morals to act as decent, respectable human beings.
Nick Carraway, the main character in the book, seems to be that decent, respectable human being. He is the voice of reason in the story. It is through his point of view that we can distinguish who is corrupt and who isn't. Nick even says he is an honest man, which gives him some credibility. He gives a vivid depiction of each character he meets over that summer, and every one of them except a humble garage mechanic, George Wilson, is claimed by greed and wealth in one form or another.
For Tom Buchannan, his greed came in the form of another woman. The wife of George Wilson, Myrtle Wilson, is his mistress. He is corrupt because he is being disloyal to his wife Daisy and George Wilson. His wealthiness is a reason he is disloyal because he can use his money to get any woman that he wants. Tom is hot tempered, ready to snap at anyone who gets in his way. He is also a racist, always talking about the "White Race” needing to conquer all. .
"It's up to us who are the dominant race to watch out or these other races will have control of things.” Tom is the perfect example of the kind of amoral people described in the book. Greedy, ignorant and wealthy.
Myrtle Wilson is just the same. She is dishonest towards her husband and speaks highly of herself. But she is one over Tom because she takes him for granted. He is the one buying all of her clothes and beauty accessories. He even went as far as to buy her a dog. This doesn't seem to bother Tom a bit though. At her party in New York, things turn a bit sour though. Tom and Myrtle are fighting about something when Myrtle brings the name Daisy into the argument. Hot tempered Tom gets upset with Myrtle and actually breaks her nose.