“These days,” said Lee Epstein, a law professor at Northwestern and an authority on the court, “we’ve moved to other sources of diversity,” including race, gender and ethnicity.

That move reflects a profound shift in the way we think about law, and in the very meaning of identity politics.

On the one hand, the job of Supreme Court justice now seems to require a very specific set of qualifications. Except for Justice Stevens, all the current justices attended law school at Harvard or Yale.

Like Justice Stevens, all served on federal appeals courts before their appointments, in a break from the historical practice of including leading lawyers and politicians in the mix. And all members of the current court, except for Justice Stevens and Justice Anthony M. Kennedy, were elevated from appeals courts in the Boston-to-Washington corridor.

Image CHANGE Justice John Paul Stevens and Justice Sonia Sotomayor in 2009. Credit... Doug Mills/The New York Times

On the other hand, society seems to demand that the court carry a certain demographic mix.

It is hard to imagine the court without a black justice, for instance, and it may well turn out that Justice Sonia Sotomayor is sitting in a new “Hispanic seat.” It would surprise no one if President Obama tried to increase the number of women on the court to three. Not so long ago, there was similar casual talk, but of a “Catholic seat” or a “Jewish seat” on the Supreme Court. Today, the court is made up of six Roman Catholics, two Jews and Justice Stevens.