You didn’t forget Jeb Bush was still running for president, did you? I did, on Monday, for a moment, when the Iowa results were coming in. The New York Times website featured a leaderboard with Ted Cruz on top, followed by Donald Trump, followed by Marco Rubio, Ben Carson, and Rand Paul. Oh, that’s how everyone did.

Finally I noticed that Bush wasn’t even on it. He was down on the expanded leaderboard, with Rick Santorum and Mike Huckabee. Santorum and Huckabee saw the Iowa results and quit. Rand Paul finished 1.7 percentage points ahead of Bush and quit.

Jeb Bush did not quit. Jeb Bush is in New Hampshire, campaigning. After that he plans to move on to South Carolina, with his family in support, to turn 63 with a program the Times describes as “birthday campaign fun.” Please clap for him. What he is going through at the moment seems to be mortifying, but it’s not, really. Or if it is, it’s mortifying for everyone.

The sad truth is that Jeb Bush is looking at the Republican campaign the way a great many political observers are, only he doesn’t have to click through to the “others” tab to see where he is. He is in the Republican race. And the Republican race is, if you approach it from a certain set of reasonable-sounding premises, trapped in a logical loop:

1. Donald Trump can’t really be the nominee, because his candidacy is a bizarre and unsustainable media phenomenon.

2. Ted Cruz can’t really be the nominee, because he is incredibly loathsome to the normal human beings who vote for president.

3. Everyone else who could be the nominee is currently being beaten by Donald Trump and Ted Cruz.

This is the Escher staircase that Jeb Bush is trudging up. He has to believe he can’t lose to Trump. He has to believe he can’t lose to Cruz. So he can’t believe that he can’t win.

What about Marco Rubio? Marco Rubio is, to be sure, several steps ahead of Bush on the staircase. This is why he declared victory in Iowa after finishing third. Rubio believes that the logic of not-Trump and not-Cruz points inexorably to Marco Rubio.

Rubio is less lonesome than Bush in his line of thinking, but is he necessarily right? There is an idea that the Republican establishment, such as it is, is prepared to rally around Rubio when the time comes. But, like most of the rest of the case for Rubio, that conclusion is an indirect one. Barack Obama, the Republican theory goes, was a lightweight mediocrity who only became president because people liked the idea of a youthful, minority president. So if “youthful” and “ethnic” is the political brand that will succeed, then Marco Rubio is the person who represents that brand in the Republican field. It’s one step up from nominating Clint Eastwood’s empty chair.

Assuming that Rubio is next in line would also require that, after Cruz and Trump were to flame out, he would capture the anti-immigrant faction they’ve stirred up, despite his earlier dalliance with sponsoring immigration reform.

But the more straightforward flaw with Rubio as a strong candidate-in-waiting is, again, that Rubio himself is also losing to Trump and Cruz. From Bush’s point of view, since he is competing in the not-Trump, not-Cruz branch of the race, if he were to drop out now, he would be conceding to Rubio—his own child-apprentice in Florida politics. Jeb Bush has seen his seniority trampled on by one of his inferiors before, but he was obligated to put up with it then.

Rand Paul had the freedom to drop out of the race, because Rand Paul’s ambition was to be an alternative kind of Republican candidate, and alternative-minded Republican voters had clearly settled on Trump or Cruz. Bush wants to be the normal Republican candidate. How can he quit with that position still unclaimed?

It’s the same reason Chris Christie and John Kasich are still in the race, albeit at lower burn rates than Bush. It’s the reason Michael Bloomberg is leaking and polling about a third-party candidacy. As long as the reality makes no sense, keep holding on to the dream. Clap your hands if you believe.

Image by Jim Cooke, photo via Getty. Contact the author at scocca@gawker.com.