Bob --

You have hit upon the best answer to the theological "argument from evil" against the existence of God, i.e., the argument that an omnipotent, benevolent god cannot exist because there is evil in the world.

It is conceivable that the set of physical laws that create a world in which conscious beings exist is not logically separable from those that create a world in which tsunamis and earthquakes kill hundreds of thousands of them. If there are to be conscious beings at all, then there must be natural disasters. God, omnipotent or not, cannot create one without the other any more than God can create a world in which 2+2=5.

I don't see the problem. There seems to be no logical reason that local laws can't change because of arbitrarily complicated nonlocal rules. You can even see nontrivial examples of this in practice in some modern technology. Various of Microsoft's operating systems have reportedly contained substantial amounts of code to recognize particular usage patterns characteristic of particular old applications, and change the rules so the old application continues to work even though it depends on old behavior which has otherwise disappeared from the new operating system. Vaguely-similar principles of global patterns changing local decision rules also appear, in less-nauseating ways, in all sorts of software for solving hard optimization problems (optimizing compilers, finding the optimum move in Chess, finding the optimum schedule for a big logistics operation...). What would go impossibly wrong if you rewrote physics with added rules which recognize patterns characteristic of presence or absence of patterns (like "living organism" and "magical incantation") and which rejigger the local rules as a consequence?

Changing the local rules specifically to stomp out technology without making the rest of the universe's behavior unrecognizable is a tricky job, since you are correct that everything tends to be cross-coupled in weird ways. But I think one could at least make existing technology pretty frustrating. One way to start would be by making a list of a hundred or a thousand technogically useful patterns (things heating up to combustion temperature, things bending around a fulcrum, sizable things rotating or oscillating many many times without changing shape, lots of energy being stored for a long time in an elastic object) and make case by case hacks to damp them out (spontaneously cooling things when they rise above 100 degrees Celsius, letting the lever soften and bend, etc.) whenever they weren't preceded by the suitably magically approved pattern of causality. (So, e.g., you can light a fire with a spell, and perhaps by striking suitably hard objects against each other, but not with a match or a magnifying glass. And you can use hinges as long as they are between bones in a living organism.) The result would be a very weird universe, but if I remember correctly (from long, long ago), the universe in those books was supposed to be very weird anyway.

Fascinating. A few days after I read this, it struck me that a form of Newcomb's Problem actually occurs in real life--voting in a large election. Here's what I mean.

Say you're sitting at home pondering whether to vote. If you decide to stay home, you benefit by avoiding the minor inconvenience of driving and standing in line. (Like gaining $1000.) If you decide to vote, you'll fail to avoid the inconvenience, meanwhile you know your individual vote almost certainly won't make a statistical difference in getting your candidate elected. (Which would be like winning $1000000.) So rationally, stay at home and hope your candidate wins, right? And then you'll have avoided the inconvenience too. Take both boxes.

But here's the twist. *If* you muster the will to vote, it stands to reason that those of a similar mind to you (a potentially statistically significant number of people) would also muster the will to vote, because of their similarity to you. So knowing this, why not stay home anyway, avoid the inconvenience, and trust all those others to vote and win the election? They're going to do what they're going to do. Your actions can't change that. The contents of the boxes can't be changed by your actions. Well, if you don't vote, perhaps that means neither will the others, and so it goes. Therein lies the similarity to Newcomb's problem.

It's a great puzzle. I guess this thread will degenerate into arguments pro and con. I used to think I'd take one box, but I read Joyce's book and that changed my mind.

For the take-one-boxers:

Do you believe, as you sit there with the two boxes in front of you, that their contents are fixed? That there is a "fact of the matter" as to whether box B is empty or not? Or is box B in a sort of intermediate state, halfway between empty and full? If so, do you generally consider that things momentarily out of sight may literally change their physical states into something indeterminate?

If you reject that kind of indeterminacy, what do you imagine happening, if you vacillate and consider taking both boxes? Do you picture box B literally becoming empty and full as you change your opinion back and forth?

If not, if you think box B is definitely either full or empty and there is no unusual physical state describing the contents of that box, then would you agree that nothing you do now can change the contents of the box? And if so, then taking the additional box cannot reduce what you get in box B.