Most Interesting Question.

[Pirate]

I had another thought... if it is all predetermined, surely identical siamese twins would have similar dreams, no? Surely only experiencing everything a foot to the left would not have such drastic impact on relaxed thought processes in comparison to their sibling 1 foot to the right?

Or is our mind more of a random thought generator?

To answer your first question, you are looking at too macro a scale. Every cell, every molecule is interacting with a completely different environment. You may be driving the same kind of car as hundreds of other people on a highway, but if you crash into the car in front of you, not every Nissan Sentra crashes into the car in front of it.

<edit> bad analogy because that implies simultineity. You can have the same NASCAR race on the same track with the same cars and the outcome will never be the exact same. Minor differences in the relative position of cars, heat of the road, sun in a driver's eyes, make the cars move differently - butterfly effect and chaos.

 

[Birdjaguar]

Kurt Vonnegut's "Cat's Cradle" is an excellent satirical perspective on that question. Read it, you'll love it.

Ice 9 for the Marines I read it many years ago and loved it.

To follow up on your question, what do you consider to be the relationship between chance and free will? You can exercise all the free will you want but that doesn't mean you can control things outside your own head. Another person's free will is your chance.

Life's events seem to be made up of at least 3 pieces:
My free will
Other's free will
Chance

I want to add more but it's too late tonight so I will continue this tomorrow.