What does Feynman discover about being a member of a fraternity while attending MIT as noted in the book, Surely You’re Joking, Mr. Feynman!?

When Feynman enters MIT as an undergraduate, he joins the fraternity Phi Beta Delta. The Phi Beta Deltas seem to be divided into two factions. One faction includes the partiers and socializers (stereotypical "fraternity guys"), and the other includes more studious types (stereotypical "MIT guys"). Feynman seems to have found this arrangement advantageous. He is able to learn social skills from his more socially adept fraternity brothers, and offer them help with their homework in return. His new fraternity brothers teach him to dance and how to talk to women.