Theory:Doctor Who television discontinuity and plot holes/The Angels Take Manhattan


 * If the angels were strong enough to move that magnetic lock (which is described as being imposible) in The Time of Angels (TV story), then why can't they break steel chains or locks on a door?
 * Those Angels had the power of the Byzantium's reactor, and possibly some leakage from the infinite power of the crack.
 * Also, the Angels _did_ break in once the lights were out. Presumably the fact that they hadn't done so before didn't mean they couldn't, just that they were waiting for something.
 * No they only get in because they leave the door open.


 * Okay how do they take the form of all the statues in New York? Particularly the Statue of Liberty?
 * Liberty is a separate issue (and the very next one). Beyond that, why should it be any problem for them to take the form of all the statues in New York, given that they had no problem taking the form of all the statues in the graveyard in Alfava Metraxis? If the issue is just "where did they get enough Angels from", clearly they were either gathering from around the universe or reproducing (or both), to share in the best food source they'd ever found.
 * But all of the Angels as of late had appeared in the same base form which adds consistency. The alpha Metraxis statues were different simply because they were running out of energy and unable to support the SAME base form of an Angel. "They're starting to look like real Angels now" The inconsistency is unnecessary.
 * I'm not sure what "as of late" you're talking about. How many Angel episodes do you think there have been?
 * Anyway, it's explicitly stated in the story, repeatedly, that they're replacing all of the statues in New York, and at least early on most people haven't noticed. This makes it pretty clear that looking like the existing statues is an important part of their plan: they don't want everyone to notice them until it's too late. If a fountain cherub were replaced by one of the Blink Angels, it would be obvious. So, that's the why, which seems to be the new question. As for the original how question, I think that's already answered above.
 * The fact that the angels couldn't take the shape of the Alfava Metraxis's original inhabitants is a major plot point; the Alfans had two heads while all the angels only had one head. The decayed image of the angels was implied to be caused by the angels starving for 400 years.
 * I don't think it's that they couldn't look like Alfava Matraxi statues, I think they had no reason to. I'm willing to bet that there were never any statues in the maze of the dead before the angels showed up to make it their hiding place. The soldiers and the doctor jumped to conclusions when they assumed that they were statues of the natives.


 * Its stated that when they are seen, they transform into stone, in all there previous apperances, but the Statue of Liberty is made of metal.
 * So if they don't have to replace stone statues, why do they usually do so? There are all kinds of possibilities. Maybe a quantum-locked Angel is less noticeable of a change from stone than copper. Maybe they feel uncomfortable being metal because metal statues are less durable, so they only do it when they're really secure about being in control. Maybe metal just doesn't feel as comfortable. When there are so many obvious possibilities, and it really doesn't matter which one is true, there's no reason for the episode to explain it.
 * So they can lock into anything then? Any simple inanimate material like diamond? Seems like a copout to have "final boss" that doesn't actually do anything.
 * Why not? Stone isn't magic. It may be the easiest form, or the most useful one, or even the default if they don't put any extra energy into it.
 * As for Liberty, maybe she's not a "final boss" so much as a queen that relies on the others to feed her. Who knows?
 * Remember, we only know about the Angels from two previous stories, and even within the Whoniverse, the only useful source of knowledge besides the Doctor's and River's experiences seems to be a lost book written by a madman. We simply don't know everything. And that's almost certainly intentional on Moffat's part--Lovecraft's horror novels were much more effective than stories that lay out the whole mythology like a role-playing game guidebook.

They replaced the statues, including the statue of liberty. It not they changed the real statue of liberty to stone, they took the real one and replaced the statue with a weeping angel that looked like the statue of liberty
 * What happened Grayl's guards?
 * Presumably they either ran away or got zapped by the Angels.


 * Despite knocking Grayl over and destroying a china pot, the landing of the Tardis has no effect on anything else in the room, even the closer pieces.
 * The TARDIS _does_ have an effect on everything else. In the closeup shot when the vase falls, we see shards of paper flying around, and various other things rocking on the table. In the long shot, we see even more paper flying around and shelves rocking. In the two shots of the aftermath, the floor is covered with shards and scattered pieces of paper. Obviously it did have other effects.


 * If the Doctor can waste regeneration energy and heal others, why has he never done this before? Like with Jenny?
 * Maybe he can only do it with Time Lords? Normally, that would be a useless ability because the other Time Lord could just heal themselves (which is exactly what Jenny did, although the Doctor didn't know). But River used up her regenerations to save the Doctor.
 * The word "waste" is the key here. If he did this all the time, he probably wouldn't have even made it to his 11th life. He clearly wasn't thinking straight when he did it this time, and River chastised him for it.


 * How does no one notice the Statue of Liberty walking around?
 * How do we know they don't? That timeline could be very different from the main one that existed before the Angels took Manhattan or again after the paradox wiped it out.
 * We don't see anybody reacting because we just don't see anybody. Of course you expect the streets of New York to be full of people 24 hours/day, but if you watch the episode, the streets we see at night are all empty.
 * Actually, the streets aren't empty. When Rory is on the ledge, there are several overhead shots that show cars driving around on the road in front of Winter Quay, which would presumably mean that there would have been people near it when the Statue of Liberty was attempted to walk there. Let it also be noted that none of the cars were driving as if to escape from anything, even though it would have been quite easy to see that the Statue of Liberty was about 50 feet away from them.
 * We see 2 cars in the shot where Rory looks down. And another car in another scene. We can see into one of the cars well enough to tell that there's just a driver, no passengers. And there are no pedestrians. Battery Park hasn't been that empty since the early 19th century. And whatever explains that probably also explains why nobody is watching Liberty.
 * "That which holds the image of an angel becomes itself an angel" from The Time of Angels would mean that all of the pictures, postcards, and videos that contain the Statue of Liberty would be an angel as well. The argument could be made that the angels had already killed or eaten everyone else.
 * This could also mean that the Liberty Angel wasn't the statue of liberty in the harbor, rather it was the image from the poster of the Statue inside the Winter Quay building. This might also explain why the liberty angel was smaller than the real statue, and how no one noticed it was missing from its plinth. It never left its plinth, it let its image do all the work.
 * Hmm, I think we're getting ahead of ourselves. In a series 3 episode Stephen Moffat created and introduced one of the most frightening groups of creatures in the show's long and distinguished history. In that episode you were left with the impression you knew what the "Weep N' Creeps" looked like until the very end of the episode where the fact they could take the form of other statues was implied though not explicitly stated.
 * Over the course of the next few 'Angels' episodes more developments were presented some good (RE: "that which holds the image of an Angel...") some not so good (RE: Angel Bob).
 * The Angels, while not losing any of their established menace are, I feel, losing some of their narrative menace as Moffat is trying to use them for things they really shouldn't be used for such as this (more below).

In this case I think we know what the image of an angel looks like and an image of the Statue of Liberty is still the image of the statue even if an Angel is possessing it. Otherwise it would be more a case of the Angels taking the World than Manhattan.
 * Earlier Grayls said that no one had noticed the statues moving.
 * Yes, but that was earlier. We have no idea how long it was between hiring the first detective and grabbing River, or what happened during that time (except that Grayle apparently got more desperate).
 * It wasn't earlier. Grayle said it to River after he captured her and showed her the angel all chained up.


 * For several minutes, no one is watching the Statue of Liberty angel, so why doesn't it get them?
 * For almost all of that time, someone _is_ watching Liberty. Amy is watching while Rory climbs onto the ledge. Rory is watching while he's standing on the ledge alone, except for a couple seconds when he looks into Amy's eyes. There's another few seconds when Rory and Amy are looking at each other on the ledge and the Doctor and River are looking at them, before River turns around. And probably a few more seconds while Amy and Rory are falling (but at that point it's too late to matter). That's it; nothing near several minutes anywhere.


 * why can't the Doctor travel back in time, not in New York, but in another area, and visit the Ponds? Would that still affect this whole paradox?
 * Unless something changes in a later story, the Doctor believes that seeing the gravestone and reading the last page makes it a fixed point for him. He makes mention earlier in the episode that "once we read it, it's written in stone". So, having read what seems to be their last ever message to him (and also having read something that is literally "written in stone" on the gravestone) he believes he now knows too much to interact with that timeline. So it may not be that he can't visit them, it's more like he simply won't visit them, in fear of what would happen.
 * I am more down with can't than won't, because it happened in his timeline. He experienced it, so he cannot change it. Otherwise, he'd go back and save Adric and Rose and Donna, etc.
 * Also don't forget that the doctor read in the book "Amy's Last Farewell" and after that moment he knew that he was going to lose her because once you've read your future it's fixed. After the farewell, there was nothing he could do without creating a problem.
 * This is why I don't like this episode. At the beginning of the last series we all thought we clearly saw the Doctor get shot by the astronaut and die, this was witnessed by Amy, Rory and River and described as a fixed point. Fair enough it appeared to have been witnessed by three people who now knew the future of the Doctor's "certain" death. The Doctor also subsequently learned of his apparent death and all concurrent details to know exactly when he has to go to it.
 * As the series progressed River tried to poison the Doctor and, despite this clear description of what a fixed point is, everyone present seemed to think she'd succeeded until she was persuaded to save him.
 * Come the end of the series and we learned that Lake Silencio was chosen as a still point thus making it easier to "create" a fixed point. In this episode it appears that creating a fixed point is the easiest thing in the world.
 * We then find that what was believed to have been seen was not what actually occurred. This creates a massive problem here because it demonstrates that there can be little to no objective truth in "knowing" the future and thus the criteria used here to define a fixed point seems incredibly shaky. Reading something in the book means that, that is the future text of the book. It does not prove that what the book says is true in the same way words on a headstone are just words on a headstone, they don't prove that the person it says is buried under there is actually the person or persons buried under there or even that the other details are correct.
 * After the ending to the last season claiming a fixed point just seems a weak way to separate Amy from her "Raggedy Doctor" (see below).


 * Was the Angel Liberty the real Statue Of Liberty?
 * River, after looking at her gizmo, said the Angels had replaced almost all of the statues in New York. So: Liberty wasn't always an Angel; she was replaced by one.
 * We don't know exactly when it happened. River and Grayle have both been investigating the Angels for a few months, and it's only very recently that they've really taken over (because River sounds surprised that they've replaced most of the statues, as if last time she checked that wasn't true), but Liberty seems to be one of the earlier arrivals (given the opening scene). We can't pin it down any more firmly than that, but I don't see how that's a discontinuity.


 * If the Statue Of Liberty is (or was) an Angel, when did it replace the real one or was the Statue Of Liberty always an Angel?
 * The main characters repeatedly refered to the paradox collapsing the timeline, so none of the things on that timeline ever happened, so Liberty is the original statue, not the Angel.


 * Are we to assume the Statue Of Liberty ever since is, in fact, a giant dead Angel?
 * The main characters repeatedly refered to the paradox collapsing the timeline, so none of the things on that timeline ever happened, so Liberty is the original statue, not the Angel.


 * How did the Liberty Angel get back on it's plinth?
 * The main characters repeatedly refered to the paradox collapsing the timeline, so none of the things on that timeline ever happened, so Liberty is the original statue, not the Angel. Which means she doesn't have to get back on the plinth because she's always been there.


 * What was River doing in 1938?
 * What River's doing in 1938 is investigating the Angels, as the episode makes abundantly clear. If you're asking why she chose to investigate the Angels in 1938, we don't know, any more than we usually know why Sarah Jane, the Doctor, UNIT, etc. so often manage to find things worth investigating. That's hardly a discontinuity.


 * How was the book was written?
 * The question is completely explained in the episode. We see River talking about how she'd better go write the book so she can send it to Amy. Presumably she did so. Amy added an afterword (and possibly edited it) and got it published. There's nothing mysterious, or unexplained, or paradoxical about any of it.
 * Before you ask, yes, it's a causal information loop, and in some franchises causal loops are paradoxical and therefore impossible. But it's pretty firmly established that they're perfectly fine in Doctor Who. (For just the most relevant of the many examples, there's the "deleted scenes" in Blink). And in the real world, physicists who have looked into time travel mostly agree with Doctor Who that causal loops are fine.
 * Not sure this loop is fine; it requires the history of two different timelines to exist concurrently and then to be replaced with a third. That's not a loop.


 * How did the book Melody Malone make its way into the Doctor’s pocket?
 * We don't know how it made its way into the Doctor's pocket. As the Doctor directly said in this episode, even he's given up wondering. If leaving that unexplained is a discontinuity, it's a discontinuity in dozens of stories over the last 49 years. Most viewers would consider it a running joke, not a problem with the show.


 * Why exactly didn't the Ponds escape using the ladder that the Doctor and River used? I mean, of course it wouldn't solve the problem of Angels chasing them for the rest of their lives, but on the other hand it would be less risky.
 * The Weeping Angels were all over the place. I doubt Rory and Amy could have made it to the TARDIS without being zapped. Rory also probably wanted to kill himself to ensure that Amy could get out safely.


 * What about the future Rory from the The Hungry Earth? Wouldn't the old Rory dying in bed cause a paradox because he wouldn't visit 2020 and wouldn't that paradox poison the angels?
 * The still could have done that. In Dinosaurs on a Spaceship it was around 2020. The episode implies that they didn't do it then, but in The Power of Three they went on a bunch of adventures with the Doctor. The Angels Take Manhattan could also be one of those moments where they had adventures before the episode and could have possibly done this. So no paradox it still did happened.


 * Why can't the Doctor use River's vortex manipulation to reach the Ponds and then transport them back? We saw that a vortex manipulator can carry at least 3 at a time.
 * New York cannot handle another paradox. If River rescued Amy/Rory, then River can't get the book published. Now the Eleventh Doctor has nothing to read and will never find out what happened to Rory. Meaning The Doctor and Amy won't go rescue him in 1938.
 * Just one alternative: The Doctor jumps ahead six months and collects River's completed manuscript. He jumps back to 1939 Weehawken New Jersey.  He puts the manuscript, a couple of thousand dollars in local currency in a safety deposit box, and mails a key with instructions for Amy to have the thing vanity published, and to meet him on Christmas Day, 1940, in Weehawken.  He picks them off there, and they go on to have further adventures, living well, until Rory expires at 82 - at which point, they go back to 1988, and arrange for his burial.  Five years later, the Doctor does the same for Amy. All done, everything in writing adhered to, book and tombstone - no further paradox, the Doctor gets 50 more years with the Ponds.  Face it - this episode was moving and emotionally satisfying, but in terms of continuity and tight plot, it was a disaster.
 * Now I don't mean to come across as offensive but I feel that people aren't looking at the facts. In "Blink" when Billy Shipton was zapped back in time he couldn't contact Sally Sparrow (any earlier then the day he would die) or it would tear a hole in the fabric of space and time. Billy was a fixed point in time, erase him from being zapped and basically everything would fall apart and the Doctor would not get his TARDIS back. One great big paradox. Look back at "Blink and you will see a lot of similarities to "The Angels Take Manhattan", and then everything will seem to make sense. "The Angels Take Manhattan" was a very solid episode and it had a very neat script and I haven't seen any plot holes yet.
 * Firstly, there's nothing to stop the Doctor from using the TARDIS to transport Rory and Amy back to the right time and place when they reach the age that they die (the grave stone only states that they died at 82/87 at such a date. No indication of them what they are doing between 1938 until their deaths). Secondly, if the paradox is specifically in New York Amy and Rory still have the option of physically moving away from New York to get picked up by the TARDIS (and for the return trip when Rory gets to 82 and Amy gets to 87 just drop them off near New York and they can walk/take a cab there).
 * What if one or both of the Ponds died while on an adventure with the Doctor before reaching 82/87? That would create another huge paradox, and that is not something the Doctor wants to risk. Also, keep in mind the events of "P.S.," where it is revealed that Amy and Rory adopted a son who delivered a message to Rory's father a week after the events of The Power of Three. If they are never around to do that, then there's yet another paradox. The Doctor and Martha were able to be saved in Blink because they didn't do anything to change their timeline while in the past. Amy and Rory did not have this wisdom.
 * As I've alluded to above I agree with the "disaster" position. Firstly, Blink is a true causal loop, neither Billy or Kathy had the power to change what had, from the perspective of other parties in the loop, already happened they were mortal and if they could have found a way back they may have tried and hang the consequences. But they don't have a TARDIS to go flitting through time and space in or any knowledge of what has occurred.
 * The Doctor is a different case entirely, this ending is actually awful.
 * Throughout the story it has been established time and again that Amy is imaginatively powerful, she, with her power manged to save the Doctor from falling out of history, she could remember "true" history even when only one point of history could exist. It has been repeatedly shown that, cracks in time and the worst temporal disasters could not keep her from knowing and finding her "Raggedy Doctor" but suddenly, at the touch of an Angel she and the Doctor suddenly become impotent to reunite each other. Since when was the Doctor impotent?
 * I really dislike the ending because on the basis of the previously established evidence there is nothing that requires me to believe it yet I'm expected to.
 * I do, however, wonder now if the parallel scenes towards the end of this episode and The Snowmen have connected meanings and what those meanings could be.


 * If Rory dying by jumping off Winter Quay created a paradox and poisoned the Weeping Angels supply...then when he gets sent back in time by a surviving weeping angel...why doesn't the paradox begin again, since the angels got what they wanted?
 * It helps if you separate out the events somewhat. First the angels established their farm at Winter Quay in New York in the 1930s.  Then Rory was sent from 2012 back to the 1930s and then sent to Winter Quay.  By jumping off the roof Rory created a paradox so that version of 1930s New York had never existed; there was no farm at Winter Quay and the angels hadn't invaded.  When the lone remaining angel ate Rory it sent him back in time but he couldn't have returned to Winter Quay because Winter Quay had never existed.  There is also the possibility that Rory and Amy were sent back to a different time period, there aren't any dates on the gravestone.  The angels have traditionally timed a time jump to equate to around the human's remaining life span but not always.
 * Kathy in Blink was sent far enough back that she'd been dead for 20 years when her grandson gave her letter to Sally -- more-or-less simultaneously with Kathy getting sent back.


 * In this episode, once your future is known, it is fixed. But in "The Girl Who Waited," the Doctor mentions that sometimes the fact that you know your own future is what allows you to change the future. Contradiction?


 * Perhaps he meant that it enables you to try to change it, and since the facility in The Girl Who Waited had so many timestreams overlapping it might not play by the same rules.


 * Why does Rory's suicide destroy Winter Quay? I understand that the angels die because the paradox poisons their food source, but why does the physical building of winter quay cease to exist?


 * The Winter Quay was built by the Angels, so therefore it ceases to exist.


 * Right, but if you think of the events chronologically, it still gets me confused. First, angels build winter quay, next Rory appears, then comes the paradox that kills the angels. As far as I can see, winter quay itself should still be there minus the angels.


 * In Blink, the angels "kill" you by sending you back in time. In the Time of the Angels episode, the angels actually kill the people. Now they are back to "killing" them by sending them back in time. Why?


 * The angels displace you in time because time energy is their food. The reason they snapped peoples' necks in Flesh and Stone is because they were already feeding off the radiation from the crashed Byzantium. They had no need to get food from displacing people in time so they just started doing away with everyone.


 * Why did the TARDIS keep getting pulled back to the cemetery. When time was reset, why did they end up in the cemetery and not say central park or a new timeline version of Winter Quay or anything like that?
 * The Doctor mentioned that the graveyard was "causally linked somehow." That's really all the episode says about it.


 * The Doctor and Amy couldn't go back using the TARDIS to find Rory because New York would disappear with the strength of another paradox, right? But how did the Doctor know he ended up in past New York? When Kathy in 'Blink' was zapped from London she ended up in Hull! And plus, different angels send people to different time zones, so how was the doctor so sure he was in New York?
 * I thought they did use the TARDIS although it "bounced" off of Manhattan in 1938 and sent them to the cemetery instead. Why was the meaning of this "time distortion" and how did it impact the storyline?


 * This is how time works according to Steven Moffat. There's an established path that time follows, and it can constantly be rewritten and it is often done so by the Doctor in a harmless way. The TARDIS is brought to the cemetery in the beginning because of what happens in the end, it's a loop. Anyway, The Doctor doesn't know that they are back in time in New York. But they have died and their graves are in front of him. That's an established path of time. Now the Doctor could go back and bring them back and set up the graves or call them from a different state or whatever. But it's still rewriting time. Because they're really supposed to be dead. Under normal circumstances the Doctor could do that, but because he already created a huge monster of a paradox, playing with time would only make it worse. Even if Amy and Rory just go to a different state and send messages to the Doctor or something, they are still changing and rewriting their future that's been sort of fixed. And that's why the Doctor can't do anything about it, because it's one rewriting too many.


 * Which is nonsense. Narratively when Amy and the Doctor arrive in the cemetery the path time follows leads to the erection of a headstone that reads simply: Rory Williams. It reads the same when the four of them return.

However, when the weeping creep touches Rory it now also reads that he died age eighty-two, since a historical event explains this difference, the path of time has been rewritten. Then, when the petrus creepus is allowed to touch Amy it reads that she died age 87. So history has been changed twice. So the Doctor can't change the timeline because it would cause too big a paradox a weeping angel - the heart of the paradox - can change it twice. All the same can you provide the source for this for those who want to check it. There is so much about this "paradox" that seems contrary to what we've seen in the past. So, getting sent back to the past by an angel now creates a "fixed point" that can not be changed? Well, the Doctor and Martha were sent back by an angel in Blink and that didn't stop them from departing from 1969 in the TARDIS. Martha wasn't forced to live in an earlier generation.


 * Being sent back by the Angel is not what created the fixed point. Supposedly knowing what the future was going to be is what was supposed to have created the fixed point. Doesn't make much sense, I know, but that's what we're expected to believe.

I can see why the paradox might prevent Amy & Rory from time travel (since they already died when they fell from the building) and then were sent back by the angels (which makes it twice for Rory?) but I don't see why this paradox would affect a) the Doctor and b) River and c) the specific geographical area of New York City.

The only explanation that makes any sense to me is that Karen Gillan doesn't want to make cameo appearances in the future on the show. So this "paradox" was invented as an explanation of why we don't see the Doctor or River visiting her & Rory in future episodes. Of course, the better thing to do would have the Doctor and River visit but it happens outside of the episodes we see, it's just talked about. But the clear goal to me was not to be consistent with the timey-wimey aspects of time travel and paradox but to write an ending that would make it clear that we would never again see Amy & Rory on the show.


 * There is actually nothing Stephen Moffat can do to meet a criteria like that and whatever Karen Gillan may have wanted and whether she left amicably or acrimoniously it's always possible for her to change her mind. The precedent of the show tell us that therer are ways to get Amy to appear if Stephen Moffat wishes her to even if there can't be new material.
 * The point of this is to try and provide some me sort of closure to Amy's story so Clara doesn't just seem to be holding her place for her. Because that's how Amy's character was written and she would have travelled with him for the rest of her life and the Doctor would have let her if history had allowed it.


 * I also don't understand the causality of the book. If the book was written by future River to explain events that happened in 1938, why were events "forced" to happen (including dialogue that River wasn't around to hear) as they were written in the book? The events happened first, so River could write about them, the events couldn't have happened because of the book. It's a circular explanation that doesn't make sense even including time travel. And if you think it does, then answer me this...what came first, the events in the book or the book itself? If it was the events, then they were independent of the book. If it was the book, then how did it narrate what happened before the events happened?


 * No, no. Neither did this is how a causal loop works. Sometimes we're meant to believe that a characters steps are so ievitable that time is able to maximise the effect and display the ahead of time. This creates a problem in this story however.
 * Rory's gravestone is present from the moment the Doctor and Amy leave the cemetery, we are shown is as they leave. However, in the history of that timeline, given that all these things are fixed points, Rory died in Winter Quay in 1938, and his body remained there. Because, according to the story, the angels never let anyone leave. So that gravestone didn't belong to the history to which the Doctor and Amy traveled. So what was it? How do we understand the gravestone that first only had Rory's name on it. Then when he was sent to the past his age at death. Then Amy and her age at death too. Something that can change like that is not a fixed point. Are we expected to understand that the clever, devious angel built the gravestone to trap Rory? Because, as it is, it's presence actually makes no sense.


 * On another matter the people trapped at Winter Quay were supposed supposed to be the Angel's more than sufficient food source. What about their food source? I struggle to believe there was enough food and water in that room to sustain Rory for thirty to forty years.


 * This may have been said before, but couldn't The Doctor just land somewhere else in the future, go to Manhattan and save Amy and Rory?
 * The book is based on River's recollection of the events. She writes them as she remembers them because the book in the Doctor's pocket was written as River remembers them. The details have to stay consistent. River was at the graveyard when Amy said goodbye to the Doctor and was sent back by the angel. Then, when it came time for River to write the book, she wrote it as it had happened, which included the "Amelia's Last Farewell" title, which the Doctor would read. Amy's goodbye is the last time that she see the Doctor because the Doctor read that it was, and then River wrote it so that the Doctor could read it. Additionally, the Doctor read the afterword, which was written when Amy was a lot older, so there's already a large portion of her life that he's missed out on and knows that he did because he read that it happened. So now that there is a firmly-established cycle; let's explore the possible ins and outs:
 * 1) The Doctor can go back to Manhattan and get them: No, he cannot. He stated that the timelines are too scrambled for him to take the TARDIS back there. Even if he could go back and get them, he could not guarantee their safety. What happens he miraculously gets them out and then one of them dies on a later adventure? Is he going to risk returning to New York (which is already a huge gamble since it can't even withstand the strain of the TARDIS materializing there) to put their body in the proper grave just so that the timeline can appear to remain consistent? It's safer to let time run its natural course in this case.


 * 2) The Doctor can use River's vortex manipulator to go back and get them: Possibly, although the Doctor stated in "Flesh And Stone" that he was a very complex timespace event, so his mere presence may be enough to upset the causal fabric around New York. Additionally, the book establishes that the moment in the graveyard was the last time he saw them because River knows that it is because she lived through it. If he sees them again, then it wasn't the last time that he saw them. The paradox then destroys New York. In any event, the Doctor knows that he has missed a large part of Amy's life in which she and Rory have probably made comfortable lives for themselves (the "P.S." short animation, while technically non-canon, suggests that they even adopted a child together). To risk the stability of the timeline for the sake of going back and disrupting their life together would be rather selfish of the Doctor; it's best for him to just leave it alone.


 * 3) The Doctor can land somewhere else and they can come to him: No, because that would involve seeing them one more time, which as I explained in my previous point, would create a paradox.
 * Steven Moffat explained it as such: "...in normal circumstances he might have gone back and said, ‘look we’ll just put a headstone up and we’ll just write the book’. But there is so much scar tissue, and the number of paradoxes that have already been inflicted on that nexus of timelines, that it will rip apart if you try to do one more thing. He has to leave it alone. Normally he could perform some surgery, this time too much surgery has already been performed." Note how he suggested that normally the Doctor would suggest that they write the book to accommodate the altered details; however, as I explained earlier on, that would not work in this instance because the book is based on what River experienced, and if they change the details of it, then they change the book that the Doctor read and they create another paradox.


 * Which is why this is going to continue to be a circular and a poor ending, you've had to use three bullet points and evidence that Stephen Moffat has responded off show to defend his ending. If this was a good ending it shouldn't need this much defending afterwards but doesn't work and is causing problems because it conflicts with everything we've come to understand about Amy's story from previous adventures.


 * Everything I said, with the exception of the final quote by Moffat (which my bullets are independent of) was something that I was able to logically discern when I first watched the episode; it's just a stable time loop, in essence. Hardly the first one in Doctor Who, and not hard to figure out the logistics of.


 * First, you can't use the afterward the Doctor choose to read it because he already believed what had happened was fixed, or he wouldn't have bothered in the hope he could change it later.


 * And? Yes, it was fixed from the moment in the graveyard, but reading the afterword gave him foreknowledge that they lived a large part of his life without him, so it made it even harder to get to them. He knows he can't see them again, and if he had tried to circumvent that without reading the last page, then the last page would have probably changed. However, he read the last page, which gave him closure, but also ensured him that he missed out on part of their lives. It's just more information that he would contradict by going back for them; another paradox to create.

But this book as a fixed point idea once it's read makes no sense. What happens if they go through the journey, read the book and find several point that a different. Will there be a slightly different book next time through? That would mean they would have to do something different independently. Why don't the just stop and read the whole book? Then they'll throw all the pacing off and next time through they'll have to record that they stopped and read the whole book. It's nonsense.


 * It's a stable time loop. Everything they did is the same thing that the previous "them" had done. The book would describe everything that they're about to do, which was addressed in the episode. The Doctor told Amy "you said I'm going to break something, so now I'm going to do it." When he found out it'd be River's wrist (at which point we see the "I'm going to break something" line happen for the first time from River's perspective, which she'll then write about and the Doctor will read), he tried to refuse, but we then found out that River herself broke it, which is what she would end up writing about because the book is based on her experience. So River breaks her wrist > writes about the Doctor's "break something" line because she remembers it, and writes about breaking her wrist > the Doctor tells Amy to stop reading when she gets to the "break something" line > when the Doctor finds out what it refers to, he causes it to happen by refusing to do what the book told him. Also, if they stop and read the entire book, and then, say, leave Manhattan entirely, they would create a paradox, because they would be contradicting what they had read, which was only written because they experienced it. A future version of yourself writing about your future in a book and giving it to you is still the same thing as a future version of yourself just straight-up going back in time and telling you about your future; either you'll cause it to happen because that's what your future self did too, or you'll try to do something differently and create a paradox (think back to "Father's Day", when Rose wanted to go back in time to be with her dad when he died but then saved him; what was her reason for going back in time? There would have been no dead father to be with to prompt her to go back).

I don't remember Father's day supremely well a lot but I seem to recall the main obstacle for Rose getting what she wanting was a bunch of Reaper things that the Doctor conceded the Time Lords would have put a stop to had they not been indisposed by him. This episode was a bit different, afterall Amy's story history is a series of paradoxes. However, although I could try to give you the play by play myself and other have argued to that point a lot already on this topic. The point at the moment it that the episode isn't as instantly convincing as it should be given the sole purpose of the event. The people who object feel their objections are sound which is story reasoning for thinking the argument of the episode is somehow lacking.

 was. . . ''insert brief lead here and use past tense throughout article. See the Tardis:Tardis Manual and Layout guide if you have questions.''