Interesting QM debate going on between Kitty and Drunk, and don't let me dumb down the subject but I don't have a degree nor have I studied quantum mechanics formally, so my understanding is quite minimal. However, I feel I can somewhat relate it to the point I will soon get at.
To take QM as an appropriate example of determinsim, I suppose it is necessary to redefine it from traditional... ontological ways of arguing a god, where the idea is a plan has been made and all goes according to it, like what willow said earlier in response to ElJefe.
Say that QM is based, or its essence is probablistic by nature. Things that are 'pre determined' by QM can only be predicted by observers, meaning that if it is set up right, some things can and are deterministic relative to quantum theory. Take people for example, we often can look at trends and predict who is going to what, when and how. I don't want to make a cheesy reference to chess, but there you go. I would venture to say that it is only deterministic on a scale where conciousness isn't a variable fucking with things (which it would if conciousness was non-physical). For instance, using your cup of water example Drunk, the water inside typically doesn't just jump out of the cup if the cup is resting. I've not observed it. But (as an example of how non-physical conciousness could affect the state of something if it has true free will) I have observed a chess game where one party flung the board across the room. Lets say however, that conciousness is truly a physical construction, then yes flinging a board across the room most likely is predetermined, but it is less likely to occur on a scale of thousands of chess games taking place.
Let's try and justify determinism with QM. In a world where QM is the basis for everything, say that it can rapidly change its enviornment to allow a cause and affect, kind of reactionary determinism to take place. The very probabalistic nature of quantum physics is what allows determinism. In accordance ti the free will illusion, the moment we decide something, something is determined. Anything that affects the determined thought is enviornmental influence. Free will in and of itself would be just an illusion set up by enviornment factors. I don't see a plan behind everyhing, but perhaps the point I'm trying to make is the following.
Probability in the quantum level could be why parts of our lives are predetermined and why we have as much free will as we have. Albeit an illusion if it's physical, it is the only thing that can truly matter to us subjectively. Now even if our free will is predetermined by enviornmental factors, the free part is rendered useless, but the will remains. "Free Enough Will".
I became a Bluelighter soon after posting in the thread "Existiential Frustration", and the point I tried to talk myself into was that not everything I do is futile. The thought that my life or my will, or my conciousness was all fake, all useless in the end was a huge burdening thought. But I think that if we are how I described earlier, being predetermined only in a probablistic, reactionary sense, I don't think that THIS would take meaning out of life. Our will and conciousness would exist. Our individuality would remain the function of what we choose to take to heart, and our ability to change our determined aspects would be how we affect the enviornmental factors that contribute to determining us in the first place.
I don't mean to sound uneducated on the topic of QM, but sadly that's how it is. And it hurts my brain to think about it, but kind of a good hurt.
Through the duration of writing this comment, my opinion on determinism and its control factor changed greatly, but in that it made me more comfortable of accepting that it eliminates the free part by definition. However! I still say that conciousness could be non-physical! Then true free will COULD exist. But I guess I'll have to remain a fence sitter. But be happy that either one you choose to accept neither asserts that everything you do is useless in effect, nor is it nonexistant.
Life isn't pointless, it just seems that way if its planned out.
