The modern Supreme Court confirmation ritual dates back to President Reagan's failed nomination of Robert Bork in 1987. Democrats in the Senate mercilessly, and sometimes unfairly, picked apart Bork's academic writings as a professor at Yale Law School and his opinions as a federal appeals court judge. Bork warned that if he was not confirmed, lawyers with judicial ambitions would stop expressing controversial opinions, for fear of jeopardizing their chances.
The flaw in this argument was that Bork's controversial opinions were the reason Reagan picked him in the first place. President Obama, however, is not in the mood to pick a new fight right now. That is one reason he is drawn to Solicitor General Elena Kagan to fill the seat being vacated by John Paul Stevens. Kagan has left a very small paper trail. She was never a judge. As a law professor at Harvard she specialized in unfashionable topics that did not generate a lot of heat. Some liberals are starting to worry that she may be more conservative than the man she would replace.
Best of luck to Elena Kagan, but it is absurd to choose a Supreme Court justice on the basis of who we know the least about. This absurdity arises only because of another absurdity: the unwritten rule that Supreme Court nominees need not--indeed, should not--answer questions about their judicial philosophy, except in the broadest and most bromidic terms, and certainly should not even hint at how they might rule in specific cases.