From the moment readers meet Tom Buchanan, we know that he is a bully, an elitist, and arrogant. As Nick approaches Tom in Chapter 1, he describes him as having a voice with "a touch of paternal contempt" and emitting the attitude of

Now, don't think my opinion on these matters is final, . . . just because I'm stronger and more of a man that you are.(11)

Similarly, when Tom lapses into his spiel about Goddard's Rise of the Coloured Empires, he tries to "school" the others at the table on his white supremacy "knowledge" but is merely spewing out what he read. He tries to appear to be more intelligent than Nick, Jordan, and Daisy by belittling Daisy and simplifying his thoughts for Nick. Nick, of course, is too observant to be fooled and thinks,

There was something pathetic in [Tom's] concentration as if his complacency, more acute than of old, was not enough for him any more. (18)

Later, Tom's disdain for the attendees at Gatsby's party not only represents his elitist attitude about social classes but also demonstrates his insecurity around people who are ingenious enough to earn money or talented enough to making a living from their skills. He is archetype of humans who focus on one conversation point such as a book to try to appear intellectual.