Paradox of Time Travel in PoA - Before & After

[davenclaw]

No: HPFGUIDX 137388

--- In HPforGrownups at yahoogroups.com, "jlv230" <jlv230 at y...> wrote:

> JLV now (groans ensue...):
> I am sure this point isn't canon related, it is that you are 
pointing 
> out what you regard to be an inconsistency in the single-timeline 
> theory. I think that the inconsistency you see is not a logical 
one, 
> rather it is inconsistent with a notion you have of causation and 
> determinism, neither of which you have supported with canon. I am 
> sorry you can't make sense of the idea that something at 10pm can 
> affect something at 6pm, but as others can understand this concept 
> 

Something at 10pm can't affect something at 6pm until 10pm takes 
place, but 6pm has to take place before 10pm, right?  So there you 
have it, plain and simple.  6-10pm happens before 10pm changes what 
happened at 6pm.  If 6pm never happens without the influence of 10pm 
then all of time has already occurred and is just being witnessed.


> Your point seems to be that a `future' event may affect a `past' 
> event on the single-timeline theory. Gasp! You say this is 
> impossible, and I say that this is the whole point of time-travel!

No, my point is that before a future event can affect a past event 
the past events have to occur without the future events having taken 
place.  There has to be a time when Harry exists at 7pm without a 
time traveling Harry in the scene because he hasn't time traveled 
yet.  It's just that after the time traveling takes place all 
knowledge of pre-time-traveling events is lost.

And, um, in case you missed it, most single-timeline theorists 
insist that time traveling can't change past events, which you have 
just contradicted.


> Myself and other posters have pointed out that the dual-timeline 
> theory you propose is *logically* inconsistent, which I regard to 
> be the worst sort of inconsistency (as anything follows from a 
> contradiction). 

I don't see the logical inconsistency with a dual-timeline theory, 
but I also don't see how you can fail to see the huge problem with 
the single timeline theory.  9pm can't come before 6pm, so 6-9pm 
must take place before time traveling occurs, meaning that there is 
a timeline without a time traveler before there is a timeline with a 
time traveler.

> So we prefer the single-timeline theory. But not just 
> from this logical perspective – it is also from a canon one.
> 


Um, you mean all the canon that says that past events can be 
changed?  Oh wait, no, you ignore that canon and make up fake canon 
about how McGonagal is a hysterical liar. Or maybe that was someone 
else.


> JLV:
> I say that, from the perspective of reasoning alone, I don't even 
> think that the word `change' really can apply to the past - how 
can 
> the past *have been* one way *in the past* but *now be* something 
> different? I don't think that even makes sense. In what past was 
the 
> past different exactly?

I'll answer your question with your own words: "I say that this is 
the whole point of time-travel!"


> If you remove the book context, the timelines 
> fall apart *but* (I can hear you shouting) that doesn't mean that 
JKR 
> couldn't write her book this way! Of course it doesn't – after all 
> there are loads of books that do. 
> All I am saying is that she 
> *didn't* write it this way. In your own way, you actually said so 
too.

The timelines don't fall apart by removing the book context.  There 
is just a timeline that must have been there if time travel works 
the way it is described in her book, which she never realized and 
never wrote.  The single timeline theory is nonsensical because it 
requires the future to take place before the past, ALWAYS, even 
before time traveling takes place, and canon explicitly states that 
traveling in time can change events, which I think necessitates 
multiple timelines.

> 
> All I can say is that I really do think that JKR is writing from 
the 
> single-timeline perspective. I support this by again saying that 
> there is *only one* timeline given in the books.

Your "support" is simply JKR's mistake or ommission. She makes it 
clear that traveling in time can change past events but she 
apparently didn't consider what the events were before Harry went 
and saved himself.


> It is explicitly stated 
> that magic cannot bring people back to life. The dual-timeline 
theory 
> allows this to happen!

Harry and Hermione's time travel saved Sirius and Buckbeak, so 
apparently this is an exception.


- davenclaw