[codeulike]

Or, its deterministic, but so complex that its literally impossible to exploit the determinism to 'look ahead' in any way ... you'd need to simulate every subatomic particle, therefore needing something bigger than the universe to 'look ahead'. So perhaps the universe is like a deterministic computer that is calculating its own future. The determinism in that case just doesn't really mean anything - it can't be repeated, it can't be predicted or exploited. And so the whole problem goes away.

[pedrocr]

How does the problem go away? If you can prove your thesis then even though you can't exploit the determinism you've proven that you can't influence the future. Doesn't that mean that free will doesn't exit and is thus an extremely important result?

[codeulike]

The future is unknowable and you're part of the mechanism that is unfolding it microsecond by microsecond. The question of whether or not you can 'influence' it doesn't make any sense.

That is, Free Will as a concept doesn't really make any sense. Does Free Will mean if exactly the same situation happened twice, the person might choose different things? But its somehow different to just being random? And when does exactly the same situation every happen twice anyway? Its an incoherent concept.

In my head, I have sortof redefined 'free will' like this:

The world is a mass of cause-and-effect chains. For a given object/being, if you were to 'trace' those cause-and-effect chains, would most of the proximate links in the chain be within the object/being, or outside of it? e.g. a rock can fall and roll around if pushed, those chains of cause-and-effect are mostly outside it. Us, as humans, choose to do things using our brains, so the chains of cause-and-effect (or the first bits of the chain at least) are within our brains. Naturally if you trace the cause-and-effect far enough you will get to some external cause (memories of previous events, learning etc). But if you look at the proximate cause-and-effect chains, they're mostly in our brains. That - for me - is roughly what I take Free Will to mean. The center-of-gravity of recent cause-and-effect chains reside within us. We have it, most animals have it to varying degrees. Rocks dont have it.

[chr1]

There is also the case of several simulations of a smaller universe running in our universe, with the external observer trying to look ahead.

But even if you could simulate the universe to look ahead, most likely there is only one possible algorithm of simulation, so looking ahead is still equivalent for the tested subject living and making its choice.

So even if it can be repeated, the simulation is more like a time machine than a formula.

[excursionist]

It's possible to predict local events with a certain degree of accuracy. The better our models/knowledge and computational capacity the greater the accuracy. We can see patterns on a macro level and exploit them without looking at electrons.

[codeulike]

Sure yep, thats like the whole of science. But we can't predict things at the level that people worrying about Free Will worry about. i.e. what people are going to do next. Or what they will be doing in 15 years time. Or going further, the nightmre of determinism is the idea that someones whole life is determined before they are born and so on. That sort of thing is forever beyond the reach of all computation.