This discrepancy led to one of my favorite bits of literary analysis … An editor of a Holmes anthology on my bookshelf (somewhere), treating the stories as if actually written by the Watson character, speculated that this was intentional obfuscation on the part of the ‘author’. His actual wound, it was surmised, was in the buttocks. Watson was naturally recalcitrant to relate this, but had some trouble keeping his story straight over many years of memoirs. 
I don’t know if we consider Shoeless Joe by W P Kinsella (source of the movie Field of Dreams) to be a classic, but this is interesting, because it is the only case I can think of where the literature was wrong when it was written but reality caught up with it. The hero of that book goes to a Red Sox game and sits above the “Green Monster,” which is a big wall in left field at Fenway. For most of the history of that park, through the time the book was written and the movie was made, there WERE no seats above the GM, but now there are.
Nope. We, the audience know that it was really King Hamlet’s ghost, but the Prince does not. When the King returns, Prince Hamlet questions whether he really is the ghost of his father or a demon in disguise sent to fool him into doing evil. He becomes convinced that it is indeed his father and vows to kill Cladius as soon as possible, but soon becomes wracked with doubt.
His “To be or not to be” soliloquy later on is just a restatement of that doubt, hence his staging the play to test Claudius’ reaction.
Note ‘perchance.’ He says ‘maybe death is just a great sleep. But if it is, what kinds of dreams do we have?’ Thus the bit that comes later about
“But that the dread of something after death […] makes us rather bear those ills we have Than fly to others that we know not of? Thus conscience does make cowards of us all.”
That’s not improbable, is it? And as for the Parzival example- well, there is piebaldness.
Re the glasses in Lord of the Flies, it’s been a long tiime since I read it, and I don’t intend to read it again, but is it ever actually stated that Piggy is nearsighted? While that’s the most common cause for needing glasses, it isn’t the only, and a farsighted person’s glasses could, in principle, be used to start a fire.
Incidentally, in the Harry Potter books, Professor Trelawney’s glasses are also described as magnifying her eyes, which means she’s also farsighted. But I think that this is a nice touch for the character, and it’s nowhere stated otherwise.
I’d cut Will a little slack about the stars in their spheres. At the time, the main distinction between stars and planets was that the planets were ‘stars’ that moved against the background of the constellations, a fact of great astrological significance.
The fault ( deere Brutus ) is not in our Starres,
But in our Selues, that we are vnderlings.
(Use the little down-arrowhead below the image to find the quote.)
Another one from Frankenstein, that Stephen King points out in his non-fiction book Danse Macabre:
Frankenstein creates a woman for his first creature, but after he’s finished he imagines them reproducing and starting a new hideous race, so he destroys the woman. King points out that it would have been child’s play for the doctor to simply render the woman infertile (in fact, would have been an assload of work to make her fertile, to begin with). He could have just gave a sterile woman creature to Adam. (He named the first creature Adam, didn’t he?)
And for that matter, children of the two would likely just be normal humans, anyway. They’d be the genetic children of whoever “donated” their nutsack and ovaries.
Of course, you can’t blame Shelly for not knowing medicine, and you really can’t blame her for not knowing genetics.
I am sure this happens in literature all the time, but in my lit class we discussed how the narrator, speaking in first person, of Wuthering Heights often describes scenes she would have no knowledge of.
It’s because Cortez, with two syllables, fits the meter of the verse, while poor Balboa, with three, does not.
RE Frankenstein-
IIRC, Frankenstein never names the creature. He also gets a man of huge size by stitching together parts from normal-sized corpses. He never sees how hideous the creature appears until it comes to life ( I had to read Frankenstein twice in school. I hate it. I recommend The Frankenstein Diaries by HM Venables. Nonspoiler- In Venables’ book the creature is normal looking when first brought to life. But it is only barely alive. Further operations and procedures bring it from critical condition to health, and result in hair loss, scarring etc.). The creature is huge, fast, and strong but can live off a handful of nuts and berries.
And according to At Last The True Story Of Frankenstein by Harry Harrison “Then she had him attending the University of Ingolstadt in Ingolstadt-when every schoolboy knows that it was moved to Landshut in 1880.”
Re Narrators
Moby Dick has the same problem. Ishmael tells of scenes he never witnessed and was never told of.
Which is also true - and absolutely infuriating - in any number of movies, especially those with flashbacks.
Not to mention the Chinese film The Blue Kite, which is told to us in past-tense flashbacks–by a narrator who dies at the end.
maybe back then midnight was later than 12?
Unless the film starts with the narrator in a bar telling his story, I don’t see the problem. There are plenty of stories that are revealed to be the narrator’s life flashing before their eyes (I assume Sunset Boulevard is well-known enough that this is no more a spoiler than “It’s a sled.” ?)
Jules Verne’s “Journey to the Center of the Earth” has a lot of research on dinosaurs. Shame it’s all wrong. But hey, if scientists of the time thought an icthyosaurus was part shark, part alligator, and had to turn upside down to eat, well…
Who was he to argue with scientists? 
I don’t believe that at all. It’s one thing to trot out a causa metri argument, but for a true master and perfectionist like Keats? Nah. The most convincing explanation I ever heard for this apparent blunder was that it in fact was intentional. Keats was frequently accused of being far too undereducated and low class to be a poet. The irony of Keats reading Homer (in English, not in Greek like his colleague poets) and misattributing the discovery of the Pacific is just sublime.
That’s an odd nit to pick, considering that Frankenstein was first published in 1818 and that the entire story takes place during the 1700s.
The former bothered me too, but Shelley does address the latter. Dr. Frankenstein says that he was essentially blinded by his work – he was so caught up in putting together his creature that he didn’t step back, look at it as a whole, and realize that it was hideous. He even says that he intentionally added small details (good teeth, flowing hair) that were intended to make the creature attractive looking, but he didn’t see the “whole picture” as it were until he brought it to life.
Because of the many authors of Greek Mythology there are huge discrepancies in chronology: Heracles, for example, appears in myths that are several generations apart, being a young man both a generation before the Trojan War and then again several generations before that if you track the genealogy.
Counting the Bible as a literary work, there are multiple accounts of both Creation, the genealogy of Christ, exactly what the sin of Sodom was, and unanswered questions such as Cain’s wife (the focus of several threads on SDMB), why God could eat with a mortal in some chapters but no mortal could look upon him in others, what Noah fed carnivores when he brought only breeding pairs of most animals, etc…
James Jones changed the names of most of his characters in From Here to Eternity in the books’ sequels Thin Red Line and Whistle. Patricia Highsmith’s Tom Ripley was a young man in his early twenties in the 1950s but had aged to 35 in a book set in the 1980s.