A Time Travel Conundrum (Shades of Newcomb)

Great Debates
1

A time traveller appears to you. (He really is one, you believe that he is, and you believe it for good reasons.) He tells you that he is from the future. He just visited tomorrow, and saw that a certain man (call him Steve) is going to play the lottery. Steve is going to recieve some number of millions of dollars. This number could be zero. It could be 100. It could be any other number. The time traveller does not specify.

The time traveller also indicates a box nearby, and points out all the stones on the ground around where you are. (You’ve been walking on the beach or something.) The time traveller says he has also visited later today, and knows exactly how many stones are going to be in the box at that time. That number could be zero, or it could be any other number. The time traveller doesn’t specify.

The time traveller tells you it happens to be the case that the number of stones that will end up in the box is the same as the number of millions that Steve is going to recieve.

The time traveller also tells you that Steve is a very good, deserving individual who is sure to do a lot of genuine good with any amount of money he might recieve.

“So,” you ask, “Whatever number of stones I put in the box, if any, that’s how much money Steve will get, if any?”

The time traveller hesitates. He doesn’t know that he would put it quite that way. The fact is that the number of stones you are going to put in the box is the same as the number of millions Steve is going to recieve. But the time traveller clarifies that he isn’t saying you somehow cause steve to win that amount of money by doing things with the box and the stones. Rather, Steve’s lottery results are completely the result of whatever the normal causal processes are that go into the determination of lottery results. The balls jiggle around in the basket, and are picked out one at a time, and so on. At no point is there a way for facts about this box and these rocks to have an effect on facts about the winning lottery numbers and the number of contestants playing and so on. It’s just a coincidence that Steve is going to get a number of millions equal to the number of rocks in the box. But its no less a fact for that.

So there you are–there’s a box nearby, and some stones. You could put some stones in that box if you wanted to.

The question is, do you want to? More specifically, does anything the traveller has just told you make you want to put stones in the box? Or perhaps, even make you think you should put stones in the box?

Discuss!

-FrL-

2

My off the cuff answer? I tend to believe that, if time travel were possible, that it would cause ‘branching’ into alternate universes, and you couldn’t really effect anything anyways. In the universe that Time Traveling Joe came from, Steve wins 11 million dollars, and there happen to be 11 rocks in the box.

But, even if there weren’t 11 rocks in the box, the variables (air pressure, what have you) in the lottery ball machine should still be constant, and Steve will still win the 11 milliion. Just in the second universe, Time Traveler Joe convinced you to put 100 rocks in the box.

So, were it me, instead of worrying about rocks and boxes or any of that, I’d try to get those lottery numbers! :wink:

3

Interesting, in an irrelevant sort of way, that you set it up so that Steve wins the money instead of me, the decider. Anyway, as you can probably guess from memories of my position in the old Newcomb thread, I’ll try to put all the stones in the box I can get my hands on. If causality is to be explained as something above and beyond the kind of correlation between events which we are guaranteed of in this case, then I don’t care about causality, at least not directly; it’s the correlation that is of concern to me. The plain matter is, by stipulation of the problem, [I have good reason to believe that] the more stones I put in the box, the better things end up; whatever I choose to call the mechanism at work (or phenomenon displayed, if “mechanism” should end up being a word with too causal connotations), it’d be silly for me to not attempt to take such actions as would conventionally result in more stones ending up in the box (absent reason to believe such actions would somehow be frustrated in their attempt to do so), and thus, by proxy, bring about that good which I now can take to be logically coupled to this.

People may argue about time travel working in mysteriously “branching” ways, a la the post above, but I take it as implicitly part and parcel of the set-up of the OP that time travel is to be understood in a “single consistent timeline” fashion. Otherwise, there doesn’t seem to be much point.

4

Interesting conundrum. I’d say I’d put a good handful of stones in the box - a score or so, because Steve sounds like a nice guy and it would be shitty if he didn’t win anything. Sure, my putting the stones there would not directly (physically) cause the win, but the two are now causally linked because the traveler said so. That’s a pseudocausality that is just as effective as if there was a causal link. Doesn’t negate my free will (I could still ensure Steve gets nothing) but does tweak my do-gooder buttons.

I guess, in a way, the traveler is saying I already “have will has been putting” however many stones I eventually do. Aaaargh, Time Travel is hard - I bet that’s why the Universe doesn’t permit it.

5

One of the things that would come to my mind is that there’s no way to guarantee that the sole source for rocks in that box will be me. Say I decide to load the box full, what’s to stop some teens from using the collection of rocks as ammo to try to knock down some gulls; conversely, say I leave the box empty, someone else may end up filling it to overflowing after I leave.

What I’d probably do would be gather a large number of rocks, and then sit down some distance away, and try to lob them into the box. Kinda like skipping stones, really. Just something to do while still talking about the important stuff with the time traveler.

6

I’d go ahead and fill in the box. As I see it, either he’s telling the truth, and I’d be helping a good guy do good things; or he’s lying, in which case I might as well play along until I see evidence. If he was outright malignant, he could’ve just shown up and shot me; after all, the cops probably won’t catch a time traveller. If he’s lying, the most likely scenario, I think, would be some sort of prank; make the primitive fill up the box with rocks for no reason and film it.

7

Since the prize money comes from lottery players, it would seem that each rock you put in the box creates a million losers. Add that to your calculations.

8

Is there actually a choice? If Steve has already visited tomorrow, and seen 13 (for example) stones in the box, then aren’t you going to put that many in the box (assuming you are the only person adding/removing stones). He has already seen what you are going to do, so that’s what you’re going to do.

Even if you can change, this wont affect Steve’s win. Guy visits tomorrow, sees 13 stones and sees that Steve wins 13 million, he now goes to the previous day and talk to you, if this constitutes a change to the past, and you now put a different number of stones in the box, Steve will still win $13 million won’t he?

9

I’d get the hell out of there.

The time traveler must have visited the beach “later that day” for some reason other than just to observe how many rocks are in a box. Probably to observe or record something that happens in that location that’s an historical event in the future. It seems also likely that whatever this event is, it causes the number of rocks I put in the box to be irrelevant, since it doesn’t make any sense that what I do here could have any effect on what Steve wins. So what are the possibilities? A meteor strikes the box, or nearby, and obliterates it, or fuses the several rocks that were in the box into one single rock…or a tidal wave comes and sweeps the box away, and empties it, or deposit one or more rocks into the box… I dunno, but whatever this force is (could be natural or man-made) has enough power to erase whatever I did with the rocks and the box, and I definitely don’t want to be anywhere nearby when it happens. I might try to find safe location within line of sight of the beach so I can see what happens…or I might just leave and never look back.

Oh, and I’d punch the time traveler in the face for trying to trick me into waiting around for the A-bomb to drop, or whatever the disaster is.

Goddamn time travelers.

10

Yeah! Get your rocks off in someone else’s continuum, jerk!

11

The way I reckon it is, one of three situations is occuring:

The time traveler has just come back and changed the past, back-to-the-future style. That means anything he said about the box is no longer necessarily true, unless he gets up on the stage and plays Johnny-Be-Good to undo the damage he did by coming back in time. In this case, the damage he did was to cause me to go over and empty the box of rocks, just so I could read about the seemingly impossible event of somebody winning a lottery and getting 0 million dollars. If he wants to restore the 13 rocks to the box so that it matches Steve’s actual win, he can do it himself. With me actively trying to stop him, of course, so I can see my impossible event.

Or, it could be that the universe works the Bill-and-Ted’s-Excellent-Adventure way, and that all time-jumps that ever will happen were always part of the space-time continuum; that is, he can’t change the past, because to him, it historically already happened that he came back here and talked to me, even before the first time he looked in the box in the future. Of course, this would also mean that the universe is perfectly deterministic, and that there is no free will. Anyway, because I don’t believe that this is the scenario, and I actually believe that the first scenario is most likely, I would inevitably go over and take all the rocks out of the box in the hopes of seeing the impossible. And, either Steve would win 0 million dollars, or something else would (inevitably) come and put additional rocks in the box depite my (inevitable) efforts to stop them; perhaps the time traveler himself, or perhaps something else entirely. But it would inevitably happen, one way or another.

Or, the third possibility is that this is one of those “create another/hop to another universe” scenarios, in which case nothing he tells me about his original time stream necessarily has anything to do with my time stream anyway, so no matter what happens to the box, Steve will still win that same $13 million, or rather whatever he was going to win in my version of the universe. (Perhaps $31 million? Oh, and we all have sinister mustaches here.) So in that case I’d have no need to care, but I’d still assume this was the first scenario and empty the box…and Steve would win some larger amount of money anyway. And then I’d point and laugh at the so-called “time traveler”. Because this sort of dimension-hopping/creating isn’t really time travel, anyway, and he was a loser not to know that. (Also, he looks funny without a sinister mustache.)

12

Best bet? Put a hundred rocks in the box, change your name to Steve.

13

I would be affraid of messing up with timelines and causing some unintended consequence, like a temporal loop or the end of the universe.
So, I would look up in the papers what is an usual gain for this lottery and accordingly put in the box a reasonnable number of stones.

14

Meh, if you accidentally destroy the universe it’s really the time traveler’s fault. So, as all of existence explodes at the subatomic level, you can just blame him.

15

That’s much easier to say in Gallifreyan; in English it can only be crudely translated as “timey-wimey… stuff”.

16

I deny that the Bill and Ted’s Excellent Adventure way conflicts with free will, as I want to understand it (something like the significant ability to make decisions); you could call the B&T model deterministic if you want, I suppose, though it isn’t necessary that, say, everything about the future is determinable by information about the present/past (though some things will be to some extent, a fact which is undeniably true even in everyday life without time travel). I mean, consider the characters in that movie, after all; they weren’t depicted as will-less automatons. They made all kinds of decisions; it just happened to be that the decisions they made worked out (and had to work out) in a single consistent timeline fashion. But that doesn’t conflict with their having made the decisions nonetheless.

17

“69, Dudes!” They did not alter their conversation from the first time to the second - and I don’t think they had the sharpness of memory to make sure to recite it exactly as they’d heard it, much less the interest! (I mean, come on, they didn’t seem that interested in actively avoiding paradoxes to me; how’d it seem to you? :slight_smile: ) Ergo, they had no ability to deviate from the original wording of the conversation the second time through. And if not then, why should we think they had the ability to deviate from their fated course at any point?

It’s certain that they were living out a deterministic existence. Whether this disproves free will for you will largely depend upon your personal definition of “free will”; if you have a definition for that slippery concept that actually allows it to co-exist with determinism then no problem…but that’s not the usual use of the term, I don’t think.

18

I agree that they could not deviate from what was logically necessary, the same way I cannot both eat a pie and not eat a pie for lunch tomorrow, and thus could not both say one thing and say another thing instead. But despite these constraints of logic (constraints we labor under as well, though without it seeming as troubling when we assume such stratification as prevents causal loops), I still maintain that they were making decisions nonetheless.

I do also believe free will and determinism, in the sense that I take you to be referring to, are compatible, which is not a terribly unorthodox position, although I think it’s a slightly different issue than the specific one here, though definitely related.

19

Step 1: Get a video camera and start filming.

Step 2: Ask the time traveller what lottery it is. If he doesn’t know make him go back and check.

Step 3: Assuming he does what I ask, go check the nearest billboard with that lottery (Let’s say powerball or something) and look at the current amount up there.

Step 4: Knowing he can reasonably only get within a certain distance above the amount, or a fraction if a lot of people win, fill the box with the posted pot plus say, another hundred, some amount that pot pot just couldn’t possibly increase by in that time span (get friends if I need to). Make sure to protect the box either until the numbers are announced or I see the TT come back and check it.

Step 5: I hope I haven’t run out of battery or memory yet, after filming all the events do the following:

A. Assuming I can prove the guy travelled in time, was telling the truth, but was wrong (somehow, this is a thought experiment remember?) work out a potential model, perhaps tell the TT to do this a few more times and get back to me with some data points (assuming he can). Present this stuff to some scientists.

B. Assuming I have no proof except the video (so I can’t convince people he indeed travelled through time) and he was wrong, make a quick jot of notes just in case, but don’t present them in any fashion.

C. Assuming I have proof as mentioned in A and he was right, work out a model (immutable history? Maybe by sheer dumb luck the tide came and knocked out some rocks JUSt as the TT came to check on the box, integrety is preserved through sheer dumb luck etc). Write it down, come up with some model, potentially become a well known name.

D. No proof/right try and present the model I come up with, but expect them to not be taken seriously in a “sheer dumb luck that dude guessed right” sort of way.

20

Find Steve, convince him of what you have learned, get a written deal to split 50/50, go put a mess of stones in the box and guard it until the moment of the time traveler’s return.