An identity they refuse; an identity that they refute simply by standing there, dressed like any student of any racial or ethnic background that you might pass on a campus today.

So what has the response been? Perhaps predictably, coverage in the national media reports criticism of the students: It has "sparked chatter that they're being overly sensitive—you know, about the fact that their cultural identities are being turned into caricatures."

The posters make a point that can be hard to convey in words. As Kristina Bui, a columnist for the Arizona Daily Wildcat, said,

"It's hard to explain exactly what is so wrong about being a geisha or a sheik for Halloween. It's unsettling. It's a feeling I've always struggled to articulate—a discomfort that sort of just sits in the place between your heart and your stomach, quietly nagging. ...As a minority, you’re a character, not a person."

Why? What is there about costume and identity that makes the appropriation of costume—even stereotyped, highly exaggerated, atypical costume—feel like an attack on the self?

A long tradition of anthropological research has sketched out the ways that distinctive practices— ways of eating, dressing, and the like—have served to delimit the kinds of social clusters we refer to as ethnic groups.

Such identification is intertwined with relations of power.

Kjell Olsen, writing about minority Sámi people in Norway today, notes that since the 1960s anthropology has developed a concept of ethnicity as something simultaneously imposed by the state as a fixed, bounded identity, and experienced by the person as a feeling of belonging. Where state interests may rest in defining differences, ethnic identity is experienced as a sense of being part of something.

Olsen quotes anthropologist Renato Rosaldo's argument that everyday experiences of identity "deny order and reflect people's creativity in the way they express themselves as individuals".

Categorical stereotypes like the ones that are the focus of the "We're a Culture, Not a Costume" campaign" claim the power to name and define people. Stereotypes over-write the personal experience of identity and replace it with generalizations that might feel very foreign to the person forced to identify with the stereotype.

That's what Kristina Bui suggests when she says people wearing stereotypical ethnic costumes creates a "discomfort that sort of just sits in the place between your heart and your stomach." Her reaction to having an identity that she both identifies with (as experience) and disidentifies with (as a stereotype) appropriated is something she feels in her body.

Academic comments on the student campaign get at the same thing, if not quite so viscerally.

CNN quoted professor Jelani Cobb of Rutgers University who argued that

"to treat an entire ethnicity as a costume is something else. It suggests that people conflate the actual broad diversity of a culture with caricatures and characters....What underlies this kind of costuming is the belief that these people aren't quite equal to what we are or aren't as American as we are or that you as a person who's not [a] member of that group should be able to dictate how painful [a] stereotype should be."

There are a number of different claims being made here, not all actually on the same theme. First, there is the pure issue of stereotyping: "people conflate the actual broad diversity of a culture with caricatures." This flattening of stereotyped identities erases differences among people, differences that were experienced by someone as their own self-identity. What it leaves out are things that were integral to the identities of specific people.

Somewhat separate from stereotyping—which we can think of as flattening out diversity within a group, erasing individual distinction—is the question of otherness: "the belief that these people aren't quite equal" or "aren't as American." Not only is the group identity simplified, and significant aspects important to members of the group ignored: what is left as a stereotype is represented as lesser, as illegitimate.

Finally, there's the question of power—power to name, power to define, power to appropriate an identity, and power to "dictate how painful a stereotype should be".

What the students at Ohio University are saying is that they have the power to say how painful stereotypes are. They are refusing to be assigned an identity, refusing to have identities that they experience contorted into the shape of a costume—a masquerade that anyone can adopt at will, without having lived in their skin.

Against that fierce assertion of the defining power of material practices, how on earth can anyone suggest that they are suffering an injury by being asked not to appropriate stereotypical identities as costumes?