So, the international conflict theme was added in the movie and give a the alien a purpose. It makes the story a lot more interesting because the aliens don't left without any explanation like in the book.
But it also allows the story to unfold time paradox (china sub pot) using nonlinear time.
Still, the debate about free will that nor the book or the movie answer ! Does the free will really exist ?
I'm all up for a good debate on free-will and how its dealt with in Arrival.
I personally don't believe in free-will, in the sense that we have any true choice, although the concepts of choice, decision, will etc are still allowable of course for definitions of things that we "do".
But science/neuroscience constantly supports predeterminism. There simply isn't room for some non-physical element (e.g. a soul) to ponder and truly make decisions. There's always causality, tracing right back to the big-bang.
Now, having said that, I can understand why evolution has gradually selected for what contributes to the human experience.
We need a sense of free-will to feel in control of ourselves and our lives, and a sense of volition (remember, our actions are actually very automatic) to separate our own causality from the causality of others. We need to say "I did this, you did that" to attribute happenings to people.
It doesn't matter that conscious-will or volition are illusions, because they still have benefits to our well-being and organisation of society.
A question that arises from this is - does it matter if we became aware of our inherent automaticity and determinism?
The question that the film asks is - what if we were aware of the future in the same way as we're aware of the past? We're still determined and automatic, but we now have forwards and backwards awareness?
To be honest, I get lost with that idea. Memory is a consequence of events, which allows us to learn from and act on events. If memory goes backwards, meaning that we can learn from and act on future events, then that would change the future, and our knowing of events would keep creating new memories that then changes our behaviour. It would become impossible, in the same way that we can't remember an event from the past then act now to change that event in the past. I can't wrap my head around the idea of times arrow not being in just one direction, because I haven't met the heptapods yet.
Yeah, the original story was not really interested at all in the geopolitical reaction to the alien arrival. That's really well done. The key to getting the movie made was to add that, and make the whole story tense.
I also agree that inserting the example of a time paradox (which isn't one if there's no such thing as the passage of time) was a good strike.
Yeah, free will truly exists. Special relativity is not ultimately true, which is the claim of one version of quantum mechanics, one which is almost certainly correct, and one which can accommodate free will. I actually had that conversation with Ted Chiang, the author of the story (he comes to a sci-fi convention I sued to run).
Prepare your minds for a new scale of physical, scientific values, gentlemen.share
The key to getting the movie made was to add that, and make the whole story tense.