Paradox of Time Travel in PoA

[madam_marozi]

No: HPFGUIDX 132042

 
> If you accept that time only happens once, while you still have a
> degree of paradox, which is inevitable, you at least have a
tolerable
> paradox. 

Marozi:

Right, that paradox being basically one of cause and effect, which
may be what is bothering davenclaw so much.  What we see in POA is 
an effect (Harry saving himself) that occurs chronologically before 
its cause (Harry using the TT) and even looping on itself a little 
(Harry knowing he can do the Patronus because he saw himself do it). 
 
So this version of time travel preserves a single linear model of 
time at the expense of a linear one-way model of cause and effect.  
It's a bit brain-hurty but not inconceivable.