2193: Well-Ordering Principle

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Well-Ordering Principle
We could organize a nationwide old-photo-album search, but the real Worst McFly is probably lost to time.
Title text: We could organize a nationwide old-photo-album search, but the real Worst McFly is probably lost to time.


In the comic, Megan has found a genie lamp. A genie (or Jinn) in a lamp is a supernatural, immortal being from many fairy tales, the most well known that from Aladdin, who grants one or more wishes to the person who frees it, such as by polishing or opening the lamp. Instead of wishing for multiple wishes, flight, money, or other "traditional" wishes, Megan instead wishes to see the worst Marty McFly Halloween costume.

Marty McFly, played by actor Michael J. Fox, is a main character of the science fiction film about time travel Back to the Future, which was released, we are reminded, over thirty years ago, starting a series of sequels. The films are popular, so many people dress up as McFly or Doc Brown, the other main character, on Halloween, a holiday on October 31 when it is traditional in the USA to wear different costumes. McFly's outfit in the original film consists of little more than an orange vest, jean jacket, checkered shirt, jeans, and sneakers. It would seem difficult to get this wrong.

In the final panel, the genie questions why she would wish for something so mundane, when he has the power to grant wishes beyond her wildest dreams. Megan, being savvy of tropes, used in fiction since biblical times, points out that encounters with wish-granting entities often turn out to be traps. Genies in fiction will often interpret wishes in ways the wisher did not intend, and particularly mean-spirited ones will twist a mortal's desire into their own personal hell. Even when the wish-granting entity isn't malicious, they're often portrayed as carrying unintended consequences, such that extremely consequential wishes become extremely dangerous. So Megan tries to play it safe by wishing for something innocuous and with little room for harmful side-effects. Unfortunately, Megan appears to have forgotten the overarching trope: all wishes can be twisted against the wisher.

The genie may also be reluctant to fulfill the wish due to the insurmountable practical difficulties of fulfilling such subjective, ill-defined request. The well-ordering principle is a mathematical fact stating that every non-empty set of positive integers contains a least element; a generalization of this is the well-ordering theorem which is equivalent (given Zermelo–Fraenkel set theory) to the axiom of choice, the subject of 982: Set Theory. This principle would apply to Megan's request if there was guaranteed to be an absolute worst costume of Marty McFly. However, subjective preference, while reflexive and transitive, is not well-founded (or symmetric or necessarily antisymmetric or (semi-)connex for that matter) and is therefore considered to be a preorder, also called a quasiorder. This means that the genie may not be able to fulfill Megan's wish if the selection is based on the preferences of any one person. For example, the genie may have no opinion on the quality of any McFly costume, or might judge them on criteria completely different from Megan's. Her own criteria might apply to some pairs of costumes but not others, leading to ambiguity as to which is the worst, and no way to say whether any of the candidate possibilities are as bad as the others.

While Megan isn't explicitly wishing for a common or widely-shared opinion, the title text contemplates organizing a "nationwide" search. People's preferences can be combined, such as with a mean opinion score which, while not strictly well-ordered, is usually able to identify a single worst costume, or at least a set of costumes tied for worst place according to aggregate subjective preferences. There are many other ways to combine preferences (e.g. voting) but none of them meet all of the criteria considered desirable, as demonstrated by Arrow's impossibility theorem. There is no way to exclude the possibility that even an omniscient and omnipotent genie might be technically unable to fulfill the wish, at least without, for example, changing one or more persons' preferences or modifying the space-time continuum to retroactively change the quality of some costumes of the past. The genie could fulfill the wish by showing Megan every McFly costume ever worn, which would necessarily show her the worst by any possible definition, but could be the trap she was hoping to avoid because viewing all the "hundreds of thousands" would take an inordinately long time.

The title text may explain why Megan is interested in this wish: any means available to her would be restricted to a geographic area's (nationwide) photographs or drawings from memory. It is likely the worst costume was either never photographed, or isn't remembered accurately by those who saw it (it is "lost to time" -- which usually is just a figure of speech, but may actually be literally true in this case given the Back to the Future series' central theme of time travel). By asking the genie to show her, she might be able to see the truly worst costume without being restricted to only those for which evidence remains. Such a wish fulfillment might even require actual time travel to the time and location where the costume existed. The title text can also be interpreted as Randall's wish to know about the worst costume. So this is not Megan but Randall who has the wish to see this costume. The best we can do today is to look through all the available photos of McFly costumes. But even if one of those could be agreed upon to be the worst, there is no guarantee that there is not even worse versions that is not documented for posterity. In this interpretation, what Randall really would like is to use a dangerous genie wish to get around these difficulties.

An additional, subtle pun plays on the word "well". In European folklore, water wells are often associated with spirits which may grant wishes, similar to genies. Thus, Megan's explanation of why she made a simple request of the genie is a statement of her "well-ordering principle"; her principle for ordering wishes from wells. (See also the Well series).


[Megan rubs a lamp held in her hands. A genie appears from the end of the lamp. The genie resembles the top half of Cueball's body, with a head, torso, and crossed arms, but with a squiggle representing a puff of smoke in place of his legs.]
Genie: Greetings, mortal. You have freed me. I will grant you one wish.
Megan: Hmm.
[Megan holding the lamp to her side. The genie is off-panel.]
Megan: It's been over 30 years since Back to the Future came out. Since then, probably hundreds of thousands of people have tried to dress as Marty McFly for Halloween.
Genie: OK, and?
[Megan, holding the lamp to her side, talking to the genie, who is floating in the air.]
Megan: Of those people, one of them must have done the worst job.
Megan: My wish is to see their costume.
[Megan still holding the lamp and talking to the genie. The genie is exasperated, and has his hands raised.]
Genie: Not a billion dollars? Flight? Infinite wishes?
Megan: These wish things are always traps.
Megan: Just show me the worst McFly and we'll call it even.

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Still a "trap": POOF, you're now the worst McFly cosplayer; here's a mirror.

She asked about people who 'tried' to dress as Marty McFly. So unless Megan has ever tried to dress as him, I don't think she can be the answer.Barmar (talk) 00:10, 24 August 2019 (UTC)
_Technically_, Megan never used the formal "I wish" construction: she had "my wish is" and "just show me." Since the genie didn't immediately grant it in response to "my wish is," either (1) it's not possible (see other folks' comments below), (2) like Alex Trebec, he requires the proper format, or (3) we can assume that he'll respond to a direct order ... in which case, Megan will become a McFly cosplayer in a subsequent panel. :p
Considering that wishing for any of the genie's suggestions would make her a wanted criminal that stole a billion dollars, a housefly in a room full of irritable people, or a genie trapped in a lamp for all eternity, this is hardly a terrible fate. 14:04, 25 August 2019 (UTC)
Beware. The worst Marty McFly may be truly terrible. Or it could be a little kid in a costume they made out of craft paper and colored in crayon, terrible but adorable... but it could involve (1) real lightning, (2) real plutonium, (3) the band McFly, (4) actually a dog in costume, (5) actually a fly in costume, (6) Jeff Goldblum from "The Fly" i.e. fly head not Jeff Goldblum head - in costume, (7) Cthulhu - in costume. (The last and worst trick-or-treat you'll ever see; he would qualify.) [email protected] 14:36, 26 August 2019 (UTC)
She only wished to see "their costume". So the genie could trap her by only showing the costume, without letting her know how it looked on the wearer. In fact, the genie can also opt to ignore the "singular they" madness and bury her in a pile of costumes (of everyone who ever wore one for Halloween). 16:50, 26 August 2019 (UTC)

  • Are* costumes well-ordered? Even leaving aside the subjectivity of any ranking, there are several different criteria which could be used, and many ways of combining them. (What if the costume which looked least like Marty wasn't the ugliest, nor the one showing least effort?) — Also, may be worth qualifying the explanation of Halloween by mentioning the USA; some other countries don't celebrate it, and of those that do, not all do trick-or-treating or dressing-up &c. Gidds (talk) 00:23, 24 August 2019 (UTC)
Saying there are different criteria kind of overlaps with saying the ranking is subjective. But far worse, even individual preferences are preorders aka quasiorders, which absolutely does mean that there may not be a worst, or even a set of costumes tied for worst. However, the fact that you can always find someone (e.g. on Amazon Mechanical Turk, or off the street, or on a wiki somewhere) to give you another opinion means that well-foundedness can be rescued with their mean opinion score. I wonder if the genie is powerful enough to know the asymptotic MOS ranking right away, or if it will have to wait for enough Amazon Mechanical Turk HITs to be completed. Given that there must have been at least hundreds of thousands of consumes so far, that could take quite a long time to achieve p<0.05. 04:00, 24 August 2019 (UTC)
I've spent way too much time on this, but the more I do, the more I think Randall is trying to say something about the simulation hypothesis, related to the theme on Watch Room (warning: somewhat creepy but otherwise ok sci-fi short.) 12:32, 24 August 2019 (UTC)

I hope this Munroe lowkey challenging the internet, that we might actually celebrate our infamous king (or girl marty queen) of crappy costume. -- 00:37, 24 August 2019 (UTC)

The "worst McFly" and "even" sounds like there should be a math pun in there somewhere, but I don't see it. 01:36, 24 August 2019 (UTC)

"It's been over 30 years since Back to the Future came out." That makes me feel old. Isn't that something that Munroe does regularly? Should that be mentioned in the explanation? 10:42, 24 August 2019 (UTC)

Yes, I am sure there have been at least two comics where the often surprising ages of things formed a central part of the theme, but I can't remember enough about them to find them. Anyone? 11:55, 24 August 2019 (UTC)
Just see Category:Comics to make one feel old :-). --DaB. (talk) 12:29, 24 August 2019 (UTC)
Thanks  Done 12:38, 24 August 2019 (UTC)

"The real Worst McFly is probably lost to time" is also a pun regarding the fact that Back to the Future is a time-travel story.--MCBastos (talk) 17:20, 24 August 2019 (UTC)

I wonder if this could be trap from Megan - even unintended one: in some stories, the Genie could get into problems if he CANT fulfill the wish ... -- Hkmaly (talk) 22:07, 24 August 2019 (UTC)

Even if "preference" is a total order (i.e. connex and anti-symmetric, I think both of these are debatable) it isn't necessarily a well order, however, since the set of costumes is finite, there would still be a "worst" one. Probably not Douglas Hofstadter (talk) 03:17, 25 August 2019 (UTC)

It's not a total preorder unless you don't let people have "no opinion" about some pairs, which is an acceptable constraint for preferences based on established objective criteria, but not something so subjective like quality of fashion. In practice, a lot of people are going to have least favorites between which they don't care. Surveys of subjective preferences almost always allow people to say that they don't have opinions or are not sure. Even in technically objective measures, like short- versus long-term bond yield curves, you can sometimes prove that people objectively should have certain preferences upon which they are clearly not acting. 07:40, 25 August 2019 (UTC)

Sounds like a trap -- for the genie. Keep it busy so that it can't inflict "wishes" on others. Much more subtle than "find the last digit of pi", but possibly still a "halting problem" that can never be fully solved.

Actually, this wish is simply if not easily fulfilled, and it may indeed be a trap for Megan. Simply show her every Marty McFly costume ever worn. At some point she would have to have seen the worst, no matter how worst was determined. Depending upon the method, this could take a very long time. 00:48, 27 August 2019 (UTC)

Good point; added. 06:34, 27 August 2019 (UTC)

Knowing this community and knowing the wetriffs.com story, I'm already looking forward to this year's Halloween Kventin (talk) 06:13, 28 August 2019 (UTC)

What if the genie sends Megan to the time and place when the worst McFly costume was put on... and it sends her there naked... and the genie disappears from the scene and never answers another with from Megan ever again? Trapped in another time, possibly another country with a different language, and then promptly sent to prison for years. 01:10, 29 August 2019 (UTC)

Aren't stick figures regularly naked? This isn't a low-res nudist special interest comic? 20:24, 31 August 2019 (UTC)

The person Megan would see is most likely Eric Stoltz. He was replaced as Marty McFly after the film makers (and the actor) realized he had been miscast. I propose he did the worst job of dressing as McFly (in this timeline) as he lost his job in his attempt. In an economic sense, principally that of lost potential earnings (from the movie, and further including earnings from the sequels, and from being a more bankable following a starring role in a hit movie), he would likely out rank all other contenders. Neffo (talk) 13:44, 11 September 2019 (UTC)