Who put this door here? Who am I? (Photo by Alex Wong/Getty Images) (Alex Wong/GETTY IMAGES)

Memory is a strange thing. It comes in fits and starts. You remember everything perfectly until you sit down to take the test. You forget all about the fact that you might be LeBron James’ father until he becomes an NBA star. That cherished childhood memory turns out to be something you saw on a PBS special. Suddenly you notice that you have gone out in public for the past three years without putting on pants, but it is too late: You are already Lady Gaga.

Little things like that can slip your mind.

They say that anyone can forgive, but to forget is the true mark of greatness. In which case, perhaps I am wrong: Herman Cain is a great man. He certainly seems to have forgotten a lot.

“I never forget a face,”Grouch Marx joked, “but in your case I’ll make an exception.” Replace “face” with “allegation of sexual harassment” and that’s been Cain’s stance over the past few weeks.

“Who am I? What am I doing here?” asked Admiral James Stockdale. Next that’ll be Cain. Has a flowerpot been dropped on his head recently? Someone needs to tap him gently on the head and see if things start working again.

He had to spend a full day trying to recollect what might have happened. I don’t want a president with a memory like that. Ronald Reagan couldn’t recall simple things, and we all know what happened to him.

Remember this was 12 years ago," Cain told HLN, "and I was trying to recollect this in the middle of an already busy planned day. A major speech in the morning. A major luncheon speech at the Press Club. And so the only other thing I could remember when I was asked about any specific things that were in the allegations I came up with the fact that I made a gesture by putting my hand under my chin standing near this lady saying, oh you are the same height as my wife."

This is worrisome. I know memory takes some serious effort, or at least a well-timed madeleine, but Cain has been so busy trying to recollect what happened that he has started to lose track of where we are in time. He thinks China doesn't have nuclear weapons. "Yes, they're a military threat," he told Judy Woodruff on the PBS News Hour earlier this week. "They've indicated that they're trying to develop nuclear capability and they want to develop more aircraft carriers like we have. So yes, we have to consider them a military threat."

Who am I? What am I doing here?

So much effort is Cain expending on trying to dredge up this recollection that he’s started to forget basic facts, like “agreement and settlement are functionally identical words.”

He has to do something. I would hate for him to learn what he did in the past from an outside source. That would be mortifying, and entirely too Bourne Identity for anyone’s comfort.

Try anything. Use a mnemonic device! Yes, I know that sounds painful, but something has to happen soon.

One of the women involved is currently petitioning the National Restaurant Association to release her from her non-disclosure agreement. Now her lawyer reports that she is rethinking her position somewhat. Memory, after all, is painful. Spend all your time remembering the past and you lose track of the present. You become a sad, tortured individual who only wants to talk about that one thing that almost happened eleven years ago, and Al Gore already has that market cornered.

They say the secret to happiness is a bad memory. Cain’s clearly a happy man. But he may not be soon, especially if the woman opts to speak.To forget one allegation of sexual harassment may be regarded as a misfortune. To forget both looks like carelessness.  

So Herman Cain's memory had better start working.