= 27d567bc2d48d9f40e9ccc20ea370b15)
TheOtherDave comments on Does the simulation argument even need simulations? - Less Wrong
You are viewing a comment permalink. View the original post to see all comments and the full post content.
= 783df68a0f980790206b9ea87794c5b6)
Loading…= b715d02e85f7b3b4ae65ca3d3e450868)
Subscribe to RSS Feed
Powered by Reddit
= f037147d6e6c911a85753b9abdedda8d)
You are viewing a comment permalink. View the original post to see all comments and the full post content.
Comments (102)
I basically agree with all of this.
So, when lmm invites us to suppose that the most parsimonious model that explains our observations also implies the existence of some people who we can't causally interact with, is George an example of what lmm is inviting us to suppose? If not, why not?
Semantics, perhaps.
I considered things like George's memory trace as an example of an "interaction", the same way as seeing the moonlight is an "interaction" with the moon despite the fact that the light I saw is actually from a past version of the moon and not the current one.
So maybe we were just using different notions of what "causal interaction" means? To me, "people we can't causally interact with" means people who don't cause any of our observations, including memory-related ones.
So you would say that George is not an example of what lmm is inviting us to suppose, because we can causally interact with him, because he caused a memory?
I don't think this is just semantics. You are eliding the difference between causal relationships that exist now and causal relationships that existed only in the past, presumably because you don't consider this difference important. But it seems like an important difference to me.
You're right, it is important.
But in my defense, look at the the original context:
In this context, it makes sense to consider gaps of space and time as irrelevant. This idea is supposed to work no matter what your observations are, even if space and time aren't even involved.
If I know that A causes B and A causes C, and I observe C, then I know that B is true.
We can agree to say that A, B, and C are all part of one causal network. That's how I was thinking of it. A and B are causally interacting. A and C are causally interacting. Therefore, C and B are causally interacting. If causal lines (in any direction) connect C to B, then C and B are "causally interacting". At this level of abstraction, we can even do away with causality and just say that they are "interacting" within one system of logical statements.
That's why George's memory trace causally links me to George.
A = Past George.
B = Present George
C = my memory of George.
Now that I've specified what I mean by a causal interaction, you can see why my answer to ...
...is no, since evidence for the existence of something must imply a causal interaction by my definition.
It seemed like you interpreted "causal interaction" to be a synonym for "effect". And under that definition, yeah, C cannot effect B.
Lesson learned: I shouldn't make up words like "causal interaction" and assume people know what is in my head when I say it. My mistake was that I thought most people would consider the phrase "A and B are causally interacting" to implicitly contain the information that causal interaction is always a bidirectional thing, and infer my meaning accordingly.
edit...
The whole idea I was championing is that in order to earn the label "real", something must interact with you. In other words, it must be within the same logical system as you.
In other words,
If my observation is "C" and "not F"
then "F" cannot be real. "(E=>F)&E" cannot be real. "C" absolutely must be real. "A=>B&C" might be real. "A" might be real. "B" might be real. "A=>B" might be real. "A=>C" might be real. "E" might be real. "E=>F might be real. "W" might be real. So on and so forth, with parsimony assigning probabilities to each.
...That's the definition of "real" that I was primarily defending. I consider what I just said to be opposed to the platonic mathematical definition of reality that is being proposed. The platonic mathematical definition of reality essentially proposes that two logical systems which do not logically interact in any way can both be "real", and that's what I object to. Reality is defined as things which logically interact with me. Therefore if I observe F, then not-F is false.
I do realize that this is mostly a semantic quibble over the meaning of "Real"...but the underlying "things which logically interact with me" exists regardless of what we call it, and I feel like "real" is a label that should be reserved for that. Mathematicians have already taken "true", which used to mean "real' (by my definition) and corrupted it to also mean "tautological". The Set Of All Tautological Statements already has "tautological", so can we please just reserve "real"? There are no other short words to describe "the logical system that I am contained within" left.
(Note: my somewhat exasperated tone concerning verbal appropriation is meant to be facetious )
Not just spelling fascism, I want to be sure I understand you correctly: do you mean effect or affect?
So you're considering the region that's connected by any zigzag of causal events, in any direction? We care about Bob's daughter who we never met? We care about her cousin who is now so far away that not only is she causally disconnected from us, but also from Bob?
I can't claim this is inconsistent, but it seems arbitrary. The category of people I can causally interact with (i.e. can affect and can be affected by) is a natural one, but I don't see why I should regard someone who's in a spacetime that used to be connected to mine but now isn't (i.e. Bob) any differently from someone who's in a parallel spacetime that's never been connected to my own. There doesn't seem to be any empiricallike distinction there.
Er...I think it's "effect"? I find it confusing - I think my current use falls within the exception to the noun-verb heuristic but I'm not sure.
=You interpreted "causal interaction" to be a synonym for "something which causes an alteration in another thing"
=Alterations in C do not cause alterations in B."
We consider them as real, yes.
If the proposed parallel spacetime will one day be connected to your own, then it classifies as real but currently unknowable. Upon observing evidence of the newly connected spacetime, a rational agent would discard the most parsimonious hypothesis that it had held prior to the observation. This scenario can be summed up by the phrase "What if Russel's Teapot is real After All?" (What would happen is that we'd admit that we were wrong before, but assert that we had no way of seeing it coming)
If the proposed parallel spacetime will never be connected to your own, then it isn't real.
It sounds to me like you want "affect".
To effect something is to bring it about. (In other words: to cause it to come into being; to put it into effect.) "I effected [produced] an agreement between the disputants." "They sailed away without effecting [accomplishing] their purpose."
To affect something is to influence it. (To have an effect on it.) Note that, confusingly, the verb "affect" can be defined in terms of the noun "effect".
I touched on the flower. I influenced the flower. I affected the flower. I had an effect on the flower.
I caused a commotion. I produced a commotion. I effected a commotion.
Good?
So "effect" is describing a specific cause-effect chain while Affect is describing the existence of some sort of cause-effect chain without specifying any particular one? (Overeating effects weight gain, Diet affects weight.)
"Affected the flower" and "effected a commotion" are right, but I think you'd be better of just banishing the verb effect from your vocabulary. It's extremely uncommon and I and other people associate it with pointy-haired bosses and bureaucrats.
(There is another unrelated verb usage of effect used by musicians: to effect a signal is to process that signal with an effect.)
Agreed that the words are terrible as communication tools. Is there a good substitute that i can use to talk about causality?
Ok, I think I understand your position. I maintain that it's an unnatural distinction to draw - a universe that will be connected to ours in the future, or has been connected to ours in the past, isn't empirically different from one that is and will always be disconnected from ours. Thought experiment: suppose at some point after Bob disappeared over the horizon, two copies of the present state of the universe start running in parallel - or, better, that there have always been two copies running in parallel. Although copy A and copy B happen to have coincident histories, there's no causal connection between them and never has been, so to us in universe B, universe A isn't "real" in your terminology, right (and let's assume a quantum-mechanical collapse postulate applies, so after the "split" some random events start turning out differently in universes A and B, so you can tell whether you're in one or the other)? But I assert that there's no way for us to tell the difference between bob-in-universe-A and bob-in-universe-B.
(The other example I've thought of is previous/subsequent universes in Penrose's "Conformal cyclic cosmology", but I don't think there are any important differences from the cases we've already talked about).
Empirical: based on, concerned with, or verifiable by observation or experience rather than theory or pure logic.
A universe that is totally disconnected is unverifiable by observation and experience. It lies in the realm of pure logic. It leaves no empirical traces.
Granted, there are also some possible universes that are logically connected and yet leave no empirical traces. (One example of this is the "Heaven" hypothesis, which postulates a place which is totally unobservable at the present time. So our universe has an effect on Heaven-verse, creating a unidirectional causal link... but Heaven has no effect on us. It's the same with your example - the past has a unidirectional causal link with various possible futures.)
So yes, I bite the thing you regard as a bullet. There are not necessarily any empirical differences. I still think that when the common person says "Reality", they mean something closer to my definition - something with a causal interaction with you. That's why people might say "heaven is real, despite the lack of evidence" or "Russel's Teapot might be real, though it's unlikely" but they never say "Harry Potter is real, despite the lack of evidence" or "Set theory is real, despite the lack of evidence".
All of these things can be represented totally unobservable logical structures, but only the Heaven structure is proposed to interact with our universe - so only the Heaven structure is a hypothesis about reality. The rest are fantasy and mathematics.
(If you want empiricism, I will say that the most parsimonious hypothesis is strictly limited to choosing the smallest logical structure which explains all observable things.)
Edit:
Oh cool - you've made me realized that my definition of reality implies random events create a universe for each option (so a stochastic coin flip creates a "heads" universe and a "tails" universe, both "real" | real = "causal interaction in either direction"). I hadn't explicitly recognized that yet. Thanks!
I think I'm actually fairly comfortable with that. However it does seem to run slightly contrary to layman use of "reality" and I like to keep my rigorized definitions of words as close as possible to the unrigorous layman's usage. I might be returning with a slightly revised definition which tackles some of the weirdness surrounding unidirectional relationships. If I can't find one, I bite the bullet and accept the divergence of my "reality" from layman's "reality" via "universes with randomness have many real worlds, splitting for each random event". Doesn't seem like too harsh of a bullet though - laymen's definitions aren't always internally consistent and do sometimes collapse under rigorization. If I find that I can't wiggle out of this, it does mean that I might have to think more about anthropics and slightly alter the way I conceptualize the relationship between my "utility" function and what I've been calling reality.
(I still think your ontology of "all tautologies are real" is even farther from laymen's ontology and possibly makes morality go all funny for the reasons described in my top post on the topic. Not sure whether you think distance from laymen's definitions is something worth minimizing, but figuring out how utility/morality works in your ontology is important)
I try not to say "reality" - I don't think laypeople have an intuition about the case where we disagree - that is, regions that are causally disconnected (in the sense of the relativistic term of art - whose meaning apparently doesn't align with your intuition?) from us, but can be reached by some zigzag chain of causal paths. In the Heaven case there's a one-directional causal link, and in Russell's teapot case there's a regular causal connection. Do people have an intuition about whether things that have fallen into a black hole, or over the cosmological event horizon, are "still real"?
That said, on some level you're right; I do feel that Bob is "more real" than Harry Potter. I think that's just a function of Bob's universe being more similar to my own though. If Carol in another universe has a magical cross-universe teleporter and is thinking about whether to visit our universe, it seems wrong to say she's more real now if the decision she's about to make is yes than if the decision is no. (And the notion that she's already connected to our universe because she has the choice, even if she never actually visits our universe, feels equally suspect)
(Feel free to stop replying if I'm getting repetitive, and thanks for the discussion so far in any case)
I agree; I've never felt happy with the simulation argument in any form, and trying to chase through its more extreme implications was as much about hoping to find a contradiction as about exploring things that I thought were true. Like I've said, I'm hopeful that a good theory of anthropics will dissolve these questions.
Now, that confuses me. I thought your post was largely about defining reality. Isn't the topic under discussion largely what the appropriate way to define reality is? Isn't the very premise of platonic realism that all tautologies are real?
(nods slowly)
Yeah, OK, point accepted. I had lost track of the original context... my bad.
Thanks for your patience.