A new debate is brewing over whether Barack Obama is America's first "black" president, or America's first "biracial" president. The Daily Beast's Patricia J. Williams on why the discussion is ridiculous.

It was surely meant as a wry aside when, speaking about his daughters’ search for a puppy, Barack Obama observed that most shelter dogs are “mutts like me.” My first thought, however, was: “Ain’t I a mutt, too?”

In fact, of course, we’re all mutts. As humans, we’re all descended from a common African ancestor, and have been mixing it up ever since. And as Americans, we’ve been mixing it up faster and more thoroughly than anyplace on earth. At the same time, we live in a state of tremendous denial about the rambunctiousness of our recent lineage. The language by which we assign racial category narrows or expands our perception of who is more like whom, tells us who can be considered marriageable or untouchable.

The habit of burying the relentlessly polyglot nature of our American identity renders us blind to how intimately we are tied as kin, as family, and as intimates.

In the United States’ vexed history of color-consciousness, anti-miscegenation laws (the last of which were struck down only in 1967) enshrined the notion of hypodescent. Hypodescent is a cultural phenomenon whereby the child of parents who come from differing social classes will be assigned the status of the parent with the lower standing. There are many forms—most parts of the Deep South adhered to it with great rigidity, in what is commonly called the “one drop and you’re black” rule. Take for example, New York Times editor Anatole Broyard, who denied any relation to his darker-skinned siblings and “passed” for most of his adult life: There were many who expressed shock when it was uncovered that he was “really” black. Some states, like Louisiana, practiced a more gradated form of hypodescent, indicating hierarchies of status with vocabulary like “mulatto,” “quadroon,” and “octaroon.” And even today, and despite our diasporic, fragmented, postmodern cosmopolitanism, there is a thoughtless or unconscious tendency to preserve these taxonomies, no matter how incoherent. Consider Essie Mae Washington-Williams, the daughter Senator Strom Thurmond had by his family’s black maid. She lived her life as a “Negro,” then as an “African American,” and attended an “all-black” college. But in her 70s, when Thurmond’s paternity became publicized, she was suddenly redesignated “biracial.” Tiger Woods and Kimora Lee Simmons are alternatively thought of as African-American or “biracial,” but rarely as “Asian-American.”

In contrast, many parts of Latin America, like Brazil or Mexico, assign race by the opposite process, hyperdescent. That’s when those with any ancestry of the dominant social group, such as European, identify themselves as European or white, when they may also have African or Indian parents. As more Latinos have become citizens of the United States, we have interesting examples of this cultural cognitive dissonance: Just think about Beyoncé Knowles and Jennifer Lopez. Phenotypically they look very, very similar. Yet Knowles is generally referred to as black or African American; Lopez is generally thought of as white (particularly among her Latino fan base) or Latina (among the rest of us), but she is never called black or even biracial.

Among Native Americans in the United States there is a combination of both hypo- and hyperdescent, encouraged by the interventionist history of the Bureau of Indian Affairs. Anita Hill, for example, is part Creek, but the narrative about her is entirely about African-American origin. And membership in many tribes remains closed to those who have any discernable mixture of African ancestry, but not to those with European ancestry.

All these designations mask the degree to which at least a third of so-called white people in the United States have “secret” or “passed” slave ancestors, and the degree to which almost all blacks in the United States have white slave-masters among their grand-parentage. The habit of burying the relentlessly polyglot nature of our American—and human—identity renders us blind to how intimately we are tied as kin, as family, and as intimates.

Patricia J. Williams has been published widely in the areas of race, gender, and law, and on other issues of legal theory and legal writing. Her books include The Alchemy of Race and Rights; The Rooster's Egg; and Seeing a ColorBlind Future: The Paradox of Race. She is a also a columnist for The Nation.