> If someone believes the world is purely mechanistic, then it follows that a sufficiently large computing machine can model the world

Is this controversial in some way? The problem is that to simulate a universe you need a bigger universe -- which doesn't exist (or is certainly out of reach due to information theoretical limits)

> ---like Leibniz's Ratiocinator. The intoxication may stem from the potential for predictability and control.

I really don't understand the 'control' angle here. It seems pretty obvious that even in a purely mechanistic view of the universe, information theory forbids using the universe to simulate itself. Limited simulations, sure... but that leaves lots of gaps wherein you lose determinism (and control, whatever that means).

> Is this controversial in some way?

It’s not “controversial”, it’s just not a given that the universe is to be thought a deterministic machine. Not to everyone, at least.

That's fine and well, but AFAICT the only alternative is it being non-deterministic... which doesn't seem very satisfactory either.

People wish to feel safe. One path to safety is controlling or managing the environment. Lack of sufficient control produces anxiety. But control is only possible if the environment is predictable, i.e., relatively certain knowledge that if I do X then the environment responds with Y. Humans use models for prediction. Loosely speaking, if the universe is truly mechanistic/deterministic, then the goal of modeling is to get the correct model (though notions of "goals" are problematic in determinism without real counterfactuals). However, if we can't know whether the universe is truly deterministic, then modeling is a pragmatic exercise in control (or management).

My comments are not about simulating the universe on a real machine. They're about the validity and value of math/computational modeling in a universe where determinism is scientifically indeterminable.

> However, if we can't know whether the universe is truly deterministic, then modeling is a pragmatic exercise in control (or management).

What would you say if we can predict the outcome of an experiment with 51% probability. Is that enough to establish what you call "control"? What if we can repeat the experiment as many times as we like?

(I must admit, I still don't really understand what "control" means to you, but let's get the preliminaries out of the way first.)

Choice is over rated. This gets to an issue Ive long had with Nozicks experience machine. Not only would I happily spend my days in such a machine, Im pretty sure most other people would too. Maybe they say they wouldnt but if you let them try it out and then offered them the question again I think theyd say yes. The real conclusion of the experience machine is that the unknown is scary.

> Agreed. If someone believes the world is purely mechanistic, then it follows that a sufficiently large computing machine can model the world---like Leibniz's Ratiocinator.

I don’t think it does. Taking computers as an analogy… if you have a computer with 1GB memory, then you can’t simulate a computer with more than 1GB memory inside of it.

"sufficiently large machine" ... It's a thought experiment. Leibniz didn't have a computer, but he still imagined it.

But this machine (even a tremendously large one) will have to operate in our reality and therefore can’t be “bigger” than it.