Can prayer change God's perfect plan?

[Catholic_Lady]

Well... not if the future is still determined. Whether he can see it or not... if the future is determined we cannot do otherwise.

Also... if the future is undetermined... we can't do otherwise in any meaningful sense either! If the future is undetermined that means we can't determine our futures either.... quantum randomness controlling our actions is just as unfree!

As Sam Harris has said... to paraphrase him: The free will that most people believe in is not only impossible... but its not even possible to conceptualize... and the so-called ILLUSION of free will doesn't even exist. When people think that there's this illusion where it SEEMS like they're choosing from different options... they believe that but it's not what their experiences shows them if they actually pay attention. It's a delusion not an illusion. The illusion of free will is itself an illusion. There is no illusion of free will.

I myself have lost the illusion of that illusion. When thoughts pop into my head I know they're just popping into my head.... I know I'm not picking them and I know it NEVER SEEMED like I was.... I just made the non-sequitur most people make... I found the causes of my thoughts ultimately unknown and thereby assumed I must have chosen them.... but of course there's a regress that stretches back far past my consciousness... and when something occurs in my consciousness... it ultimately comes from unconsciousness.

I now genuinely feel like I observe my thoughts, sensations and actions rather than author them.... so no wonder I find mindfulness dumbfounding... lol. I'm already mindful. It's hard to escape the present now.

My life feels like watching a very mundane movie.

Right, I personally agree it is all predetermined, but I'm trying to talk to CL starting from her point of view.  I'm trying to point out the logical inconsistency in her argument.  Sometimes that means I discuss, for the sake of argument, things that I don't agree with or believe in, like God or free will.  
We all talk about God did this or God did that in here, even though we don't believe in him.  Same thing here.

I'd like her to answer my question.

I appreciate it. 

Though I feel like I've already answered that question and given my explanations. I'm not sure how else I can say the same thing.