RUSSELL BAKER, in The New York Times, has suggested that the Democratic candidates for president are sort of like the characters in one of those murder mysteries set in a capacious country house somewhere. The weekend guests were just getting themselves back together after the first body was found in the library when the lights went off and -- Great Scot! -- when they went on again there was another body, lying right there in the dining room. This time it was Sen. Joe Biden's, of course. In fact, the playful metaphor is perfect: one by one the candidates are going to drop out or be pushed. They can't all prevail, and they can't all pass the series of tests candidates for president are put through. Those tests, so far, seem reasonable: Sen. Biden's habits of mind, as revealed in the past couple of weeks, struck us as disqualifying in a candidate for the presidency.

There has been a lot of curiosity expressed about who tipped off the press or otherwise caused Sen. Biden's downfall by getting his borrowings and his misstatements before the public. In this political city there can't be anyone who doesn't want to know. But the identity of anyone who may have helped get the word out has nothing to do with the word itself, nothing to do with the merits of the Biden behavior. Don't get us wrong: we don't think he robbed a bank or committed a murder or perpetrated a treasonous act; the dissemblings and dishonesties at issue never sank a troopship or impoverished an orphan -- they merely revealed something about Mr. Biden's nature that could not be explained away or tolerated politically. So he got out.

He did so, we thought, with ease and grace, at least relative to some of his predecessors over the years, and hinted that he may be back as a candidate at some time in the future. This must have been a grueling week or two for the Delaware senator, but say this for him: he never turned mean. Unlike Gary Hart, he also has a full-time political job to hang onto; he did not give up the Senate to run for president and is, at the moment, exceedingly busily employed. He was also no front-runner. So the blip on the screen will be much smaller than that when Mr. Hart got out.

Mr. Biden's revealed failings were not enormous, but they were serious and they were real. He did the right thing yesterday.