When Rachel Decosse ’07 eats lunch with her Phi Mu sorority sisters, it’s more than a social exercise. Her observations are research for her Philosophy Capstone project about the inner workings of teenage girls, what she calls an “honor culture,” or a “girl world.”

“If you put a group of girls in a room, you can detect different interplays,” says Decosse. “Every girl and woman of every age is a part of this culture, whether she wants to be or not.”

The Philosophy and Political Science double major is writing a 30-page Capstone thesis for each of her majors. The Capstone, a culminating experience for seniors, may involve research, in-depth investigation or original creative expression, and includes written and oral components.

For Decosse, studying honor culture has been both a research and life experience, one in which she and all the women she’s spoken to about the subject relate.

“Once you start listening to the theory, it starts to make sense,” she says.

The honor culture, most obvious among middle and high school girls, sets a ranking system within the group, establishing a leader and followers. It is a world of extremes, where girls are defined as either tramps or prudes, and where participants pick sides in every disagreement.

In the honor culture, according to Decosse, there are unspoken rules, codes and punishments between girls. If a rule is broken, even a rule as simple as clothing choices or who liked a boy first, other girls may punish the offender by ignoring her for a set period of time – what Decosse calls a “freezing out period.” The worst possible moral violation in a culture of honor is disrespect. Among men, this would mean calling one’s masculinity into question, whereas in the girl world, it translates into calling one’s femininity into question.

“This thesis is new, interesting and original, and I think there is something potentially publishable here,” says Peter Bradley, assistant professor of Philosophy and Religious Studies. “It’s possible that this project could go in a lot of ways.

Bradley says Decosse is covering new ground with her Capstone, since previous studies of the honor culture have been largely about and by men.

“Men are not a part of the ‘girl world,’ so they have not recognized that this culture exists,” adds Decosse. “I am just giving a name to a culture that has always existed.”

After graduation, Decosse plans to move to Los Angeles and intern at a lobbying firm.