The n-Category Café

Was it Landau who made that comment about Littlewood?

More importantly, what probability do you give James Dolan?

There’s also the case of the (typically British) double-barrel-named people like Swinnerton-Dyer who people who only know the names of theorems/lemmas/conjectures, eg the Birch-Swinnerton-Dyer conjecture, believe to be multiple people. Equally, Birch deserves half the credit rather than the third he gets from naive dash counting.

Osama bin Laden, Santa Claus and Pythagoras walk into a bar

“So, what will you three bearded gentlement have?” asked the bartender.

“Nonalcoholic beer,” said Osama. “No chaser. I feel sorry for anyone who is chased all the time.”

“A glass of milk, and some cookies,” said Santa Claus. “Also, a pencil and paper. I’m making a list…”

“I’ll have a bowl of chili,” said Pythagoras. “But only if it has no beans in it.”

The bartender serves them all. He hands them each a bill. They all look at each others’ bills. “Hey,” says Pythagoras, pointing at Osama and Santa. “How come mine is equal to the sum of those two squares’?”

Tim Silverman said,

I don’t really know what it means for a lot of these people to have existed. Does 5% mean there was a real person who did 5% of what the legendary figure is said to have done? Or that there’s a 5% chance that there was anybody at all that did any of it? Or that there’s a 5% chance that the current legend has a continuous history of retellings back to a completely different legend which mentioned the name of a real person?

Adam, Helen of Troy and Thomas Bayes walk into a bar…

Tim Silverman wrote:

I don’t really know what it means for a lot of these people to have existed.

True, it’s a real head-scratcher. Not only don’t we know if they existed, we’re not even sure what it would mean for them to have existed! Their very definitions are so fuzzed-out that any method of making them precise seems hopelessly arbitrary. It’s a problem of identity that makes the philosophers’ puzzle about Hesperus and Phosphorus (the Evening Star and Morning Star) look like a piece of cake.

It’s fascinating how much of human culture involves mysterious figures like this. It’s an inevitable consequence of oral traditions, I guess. Here’s a nice example of a historian trying to grapple with this:

• Thomas Green, The historicity and historicization of Arthur.

Among other interesting things, he writes:

Many different theories are available as to the ‘identity’ of Arthur and some brief methodological notes will be found here regarding the making of such identifications. While these theories are interesting, they fail to address fully one important question — was there a historical post-Roman Arthur? Many books, articles and web-pages simply make the a priori assumption that there has to be a historical figure behind the Arthurian legends. Such an assumption is totally unjustified. As anyone at all familiar with medieval literature in general will know, the historicisation of non-historical/mythical personages — often through association with some important event of the past — is not in any way an unusual occurrence. Some examples of this that will probably particularly interest readers of this article are Hengest and Horsa, who were Kentish totemic horse-gods historicised by the 8th-century with an important role in the 5th-century Anglo-Saxon conquest of eastern Britain (see Turville-Petre, 1953-7; Ward, 1969; Brooks, 1989; Yorke, 1993); Merlin (Welsh Myrddin), who was an eponymous founder-figure derived from the place-name Caer-fyrddin and historicised with the deeds of one Lailoken (see Jarman, 1991); and the Norse demigod Sigurd/Siegfried who was historicised by being associated with a famous historical battle between the Huns and the Burgundians dated 437 AD, in the Nibelungenlied (Thomas, 1995, p.390). Given this, no a priori judgements can be made as to whether a figure is, in origin, historical, mythical or fictional — each individual case must (and can only) be decided by a close examination of all the relevant material. When we have figures such as Arthur being portrayed as historical we are therefore, on a very basic level, looking at either a historical figure or a legendary figure who became historicised, with neither explanation enjoying priority on a priori grounds — it must be recognised that one can only say that there has to have been a historical Arthur once all the material has been evaluated and this has been shown to be the case; there is no possible justification for simply assuming this.

[…]

With regards to the whole question of historicity and historicisation, it has been suggested that, rather than ask whether there is any justification for postulating a historical Arthur, we should ask whether any candidate fits the ‘facts’ — certainly the undertaking of such an exercise is very beneficial but it probably doesn’t actually show anything, at least with regards to historicity. To take an example, several people have suggested, over the years, that Ambrosius is Arthur on the basis of Historia Brittonum Chapter 56. However, what they see can be one of two things — either they are seeing the ‘truth’, that Ambrosius was Arthur, or they are seeing a partial truth, that the portrayal of Arthur in these sources was based on Ambrosius but that this is a secondary development of a folkloric Arthur; in a sense Ambrosius was Arthur but not in the sense that most people would mean when seeking an answer to this question. How does one get away from this? The only way I can see is by adopting the above methodology, by asking what justification there is for postulating a historical Arthur. Indeed, it should further be pointed out that there are certain dangers in looking for characters who ‘fit the facts’ — to take the example of Chapter 56 of the Historia Brittonum once more, with sufficient ‘imagination’ and linguistic gymnastics, as has been noted, the list of battles in this Chapter can be made to fit just about any locality one can think of and as such these theories are mutually cancelling and methodologically indefensible — thus Collingwood (1929) succeeded in ‘discovering’ all the battles in the south-east, which happily fitted his theory that Arthur only fought the Jutes; Anscombe (1904) ‘found’ that all the battles were fought in the Midlands; and Skene (1868, I, pp.52-8) ‘discovered’ that all the battles could be identified with places in Scotland! The above methodological considerations hold whether one is looking at models for historicisation or ‘Arthurian originals’ — a vast literature has been generated, both online and offline, by the search for historical characters who ‘fit the facts’ but the simple truth of the matter is that the vast majority of these efforts are methodologically indefensible. While internally consistent, these theories are all mutually cancelling, explain only a tiny portion of the legend, if any of it, and an almost infinite number of such identifications can be made (especially when a shot of ‘ingenuity’ is added to the mix), all impossible to disprove but equally nearly all invalid.

But, I’m glad all these subtleties didn’t stop you from going through the list and giving them probabilities!

I seem to be much more certain than you! That makes me nervous.

Yes, you seem quite confident about assigning events a 0% or 100% probability. Are you often shocked by things not working out the way you expect?

I would not be terribly shocked if, say, there turned out to be a war between Trojans and Greeks that started from a marriage gone sour involving a beautiful woman named Helen… and if that happened, I might feel fine saying “Helen of Troy existed”. So, I wouldn’t assign this a 0% probability, they way you did.

Similarly for a lot of the other legendary characters.

Maybe I just don’t know enough…

Maybe you know too much! Isn’t that what causes people to assign 0% or 100% probabilities to lots of events?

Or, maybe you just know more than I do.

Johnny Appleseed was real enough. He was a business man named John Chapman, and there’s no shortage of newspaper articles and public records to confirm his existence.

There’s been some mythologizing though. Chapman wasn’t an itinerant seed-dropper. Planted orchards, left them in the care of managers, and returned later to collect his due.

Tim wrote:

Plato — 100%. How would one arrange for the disappearance of Plato? Who would write the dialogues?

James Dolan responds:

isn’t this a bit like “how would one arrange for the disappearance of dr watson?”?

I’m still getting used to the fact that a growing number of people seem to believe that my own existence is a hoax. People, that is, who know me via the blogosphere, and are skeptical.

See, for instance, the responses on Digg to:

http://www.digg.com/programming/Greatest_Nerd_of_All_Times_Jonathan_Vos_Post

By the way, there is some support for the notion that “Robin Hood” — rather than being purely fictional — was an Anglicization of the mythic version of the actual William Wallace (Braveheart).

In an old-fashioned mimeographed fanzine, APA-L, in the early 1980s, I’d coined the term and concept of “anti-solipsism.” And anti-solipsist tells people: “You exist, but I do not.” A natural idea to one who toys with duality…

Surely there’s an n-categorical generalization of this…

John Baez, I’m sorry to be noncompliant with your request. But I’ve spent scores of hours as a teacher of History of Science and Sociology discussing with students “founder myths”, the extent of estimated historicity of Christ, Moses, Mohammed (once cannot do the last in the Islamic world these days). I coincidently spent 2 hours on the Caltech campus earlier in the week discussing Christianity 1.0 (Apostles and Nazarenes), 2.0, and 3.0 (Council of Nicea) with someone (every religion begins as a cult; not every cult becomes a religion; what accounts for high fitness of some; why did Mitt Romney cite “Battlefield Earth” as a favorite novel; slaughter of the nazarenes, etc.). These are deep topics. I also spent hundreds, maybe thousands of hours making such determinations in each of over 20 centuries on my Chronology:

http://magicdragon.com/UltimateSF/timeline.html

Almost every “person” (Real or Reel or novelistic) you mention is discussed therein. I thought it better to give others a chance to play the game, after my thoughful (not flippant) references to Robin Hood and King Arthur, and not be a windbag.

Since the Greek myths are one of the few areas I’ve read enough about, here’s my probabilities for those (adding Iphigenia and Aeneas to highlight the full range of roles in the stories):

Odysseus (Ulysses): 45% like Agamemnon, may have been important enough figure for his name to graft onto the story. His role in events unlikely enough that he’s still more likely to be a literary creation.

Agamemnon: 70% hyper-important characters get grafted onto the names of real people

Iphigenia (daughter who Agamemnon sacrificed (disputed!) to get a favourable wind to Troy): 30% may possibly have existed, but the role she needs to fulfill in the narrative seems so unlikely she’s probably a literary creation

Helen of Troy: 37% possibly existed, but I doubt her beauty was sufficient to be the real basis for a war; more like an ancient version of WMD :-) .

Aeneas (Trojan who escaped giving the bloodline leading to founders of Rome in the “franchise reboot” story The Aeneid): 15% he’s very likely a “politically needed creation”; may just about have existed as a name grafted onto story.

Homer: 75% very likely but not as important as literary history suggest.

* A string theoretician in the year 2100

100%. The Technological Singularity will happen before then, you see, and the post-Singularity transhumans will have arbitrarily large amounts of computer power at their disposal. Historians among them will certainly be interested in string theory: if string theory gives anything useful, they’ll want to know how a useful description of reality came to be. Contrariwise, if string theory goes belly-up, they’ll want to know why so many people worked so hard on it for so long! Therefore, string theorists are destined to be resurrected within the simulation.

By the same “logic”, we can conclude that in the year 2100, Helen of Troy will without doubt have existed, because if she did not it would be necessary to create her. In the future, programmers will have the ability to do so (cf. The Woman in the Red Dress).