Essay talk:Some arguments against evolution/Archive2

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I can't help but feel somewhat guilty about the existence of the enormous tangle of confusion above. I'm (probably) not going to enter into this discussion for the same reason I'm on temporary wiki-break (I have way too much to do IRL), but I would like to drop a link related to the sort of skepticism Maratrean seems to be proposing. Maratrean, it seems to me that nothing you've said here prevents you from falling into such a black hole - why not question the thought processes you used to arrive at your conclusions? Tetronian ^{you're clueless} 06:03, 24 April 2011 (UTC)

Oh Tetronian, while it is good that you have a life, it would be better for me if you didn't, and then I could talk to you about this more. I find you the most thoughtful and intelligent person I have encountered here.

I think there are two basic types of radical skepticism - Pyrrho's and Descartes'. For Pyrrho, radical skepticism was not just a means to the conclusion, it was the conclusion. Everything can be doubted, so everything ought to be doubted.

For Descartes, radical skepticism was a means rather than a conclusion. His point was not that everything can be doubted - rather, try to doubt everything, and maybe in doing so you'll discover some things can't be doubted. So for Pyrrho doubt is the means and the end; for Descartes, doubt is the means, but the end is indubitability.

My approach is based on a few principles:

1. If a belief must be accepted in order for human thought, and a meaningful human life (i.e. one spent outside the asylum), to be possible, then that belief must be true.
2. If a belief is necessary - in the sense that no human can seriously entertain its falsehood - it must be true.
3. Presented with two alternatives, where the evidence for each alternative is balanced (either equally strong or equally lacking), and where the state of evidence is highly unlikely to change in the forseeable future, but where there are strong non-evidential reasons (such as pragmatic or ethical reasons) in believing one rather than the other, then the rational course is to believe as those non-evidential reasons indicate.

I think these are basic principles of rationality. Using these principles, we can rescue ourselves from solipsism, Last Thursdayism, etc.

Now, some may disagree that these are principles of rationality. Fair enough - but then, my question is, how do we decide whose theory of rationality is the right one? --(((Zack Martin)))^™ 08:45, 25 April 2011 (UTC)

Then, by your own conclusions here you should reject Maratreanism...

Also, it used to be the case that to stay out of the asylum, you had to admit that the Christian god were real... does this mean that the Christian god is true? What about earlier than that where Greek gods were necessary to believe in else it was off to the asylum (an alternative to "off to the asylum" here is obviously "death"), does this mean that the Greek gods are real? Yet, this yields contradiction, in that the belief in the Christian god requires denying the existence of other gods... so he can't be true at the same time as the Greek gods are true.

P.S. The intelligence of a person is not based simply upon their willingness to humor your position. --Eira ^{OMTG! _{The Goat be Praised.}} 18:02, 25 April 2011 (UTC)

"The intelligence of a person is not based simply upon their willingness to humor your position." This made me smile. Well put, Eira. And Maratrean, thanks very much for the compliment. That said, I reject all of your criteria for rationality. I'm not going to discuss details, but as far as I can tell we should believe in things if they are true, and that's it. Other ways of knowing shouldn't be discussed unless you can show that they are significantly better than just picking out of a hat. Also, I don't completely agree with your discussion of "necessary beliefs" because of the fallibility of intuition. Tetronian ^{you're clueless} 20:46, 25 April 2011 (UTC)

Uh-oh, someone just got told to read the sequences. Nebuchadnezzar (talk) 20:56, 25 April 2011 (UTC)

Well...yes. Tetronian ^{you're clueless} 01:19, 26 April 2011 (UTC)

Probably time well-spent, if a difficult hike. Maratreieieien, 1: Bullshit, that is not what makes anything true. 2: Interesting, but little more than "food is necessary to life". 3: More bullshit, what indeed is reason based on "non-evidential" argument? ħuman 06:43, 26 April 2011 (UTC)

Eira, Also, it used to be the case that to stay out of the asylum, you had to admit that the Christian god were real - when I say stay out of the asylum, I am being colloquial. I mean there are things you need to believe or else you'll be really, really mentally ill, you won't be able to cope with ordinary life at all. With Christianity, yes there was a time when you had to pretend to believe it to avoid getting burnt at the stake - but Christianity is something people can and do disbelieve. Existence of other minds is something which people sometimes question, philosophically, but it seems doubtful anyone has actually disbelieved it. So, Christianity and believing in the existence of other people are really different beliefs, the first is not necessary, the second is.

Tetronian, Yudkowsky can define rationality however he likes, but why should others accept his definitions? Others would define it differently - what makes his definition more right than theirs?

To say we should believe in things if they are true, well I don't agree with that at all. Sometimes the rational thing to do is to believe a falsehood, and the irrational thing to do is to believe the truth. If all the evidence supports a proposition, then it is rational to believe it - it is still rational even if the proposition happens to be false. Likewise, one can believe something for bad reasons, yet it happens to be true, but it being true doesn't make your beliefs rational. For example, young Jimmy believes there is a magical toilet stall at school, and everything written on its walls is true. One day, sitting on the toilet, he reads "Mr. Thompson is cheating on his wife!" newly inscribed. So, he believes Mr. Thompson is cheating on his wife. Is Jimmy's belief rational? No. Let's suppose its actually entirely true, Mr. Thompson really is cheating on his wife. Is Jimmy's belief now rational? Still no. His belief is true, but it isn't rational.

Human, you have rejected my principles, fair enough - but you haven't actually given any reasons for disagreeing with my principles, just stated your disagreement. --(((Zack Martin)))^™ 11:01, 26 April 2011 (UTC)

Fine then, taboo "rationality." In this discussion you are using the word to mean "the means and methods by which we evaluate beliefs." As a result, it makes perfect sense to use "what is most likely true" as a good standard for evaluating beliefs. If you want to use some other standard, then you can no longer say "this is probably true." Re the example you gave: since we don't always have access to "what is really true," Jimmy's belief was irrational. Period. Think about this thought-experiment: a physicist picks a theory of physics out of a hat. It doesn't matter if he is later vindicated, the method he used was wrong because it has an astronomically low probability of succeeding. So yes, rationality does depend on your state of information, but since we can pass evidence to each other, if we both have common knowledge then we must agree.Tetronian ^{you're clueless} 15:22, 26 April 2011 (UTC)

Maybe a better way of explaining it: we should always be able to replace the word "rationality" with "what is probably true" (except in the case of instrumental rationality). If you can't make that substitution, you're doing something wrong. Tetronian ^{you're clueless} 18:45, 26 April 2011 (UTC)

Better still: "A "logical" argument is one that follows from its premises. Thus the following argument is illogical: All rectangles are quadrilaterals. All squares are quadrilaterals. Therefore, all squares are rectangles. This syllogism is not rescued from illogic by the truth of its premises or even the truth of its conclusion. It is worth distinguishing logical deductions from illogical ones, and to refuse to excuse them even if their conclusions happen to be true. For one thing, the distinction may affect how we revise our beliefs in light of future evidence. For another, sloppiness is habit-forming." From A Rational Argument. Tetronian ^{you're clueless} 21:40, 26 April 2011 (UTC)

Tetronian, if I understand Yudkowsky's point about taboo, he is basically saying "If we can't agree on how to define the word rational, let's just do without it." But I think in saying this he is ignoring an important part of how words like rational work.

An analogy with ethics - consider the word good. The utilitarian atheist says, Whatever produces the greatest happiness for the greatest number of people is good. The Christian fundamentalist says, Whatever obeys the Bible is good. They argue about whose definition is right. Someone then suggests, "You both define good differently - let's just acknowledge you have different definitions, and stop using that word as a result." Yet, this idea is failing to understand an important part about how good is used. Suppose the argument was about blue. One person says a given shade is blue, another person says it is purple or indigo. To this argument, you don't really disagree, you just define words differently could be a useful response.

But good is not like blue, because blue performs a purely indicative/labelling linguistic function, while good performs prescriptive or imperative functions. Good is not just a label, its a call to action, an imperative - good implies Do this!. So, while a Yudkowsky style approach of it's just a difference in labelling works for blue, it doesn't work so well for good.

And this is my point, rational is quite like good. Just as good/moral/ethical implies Do this! and bad/evil/immoral/unethical implies Don't do this!, so too does rational imply Believe this! and irrational imply Don't believe this!.

A major dispute in ethics is whether good is in some sense objective - is "Murder is wrong" somehow objectively true for everyone? Or does it just mean "Don't commit murder!", and hence is not really capable of being true or false? The same issue applies to rationality, because both ethics and reason have this common element of being something which is worded indicatively yet has a strong prescriptive component - is "X is irrational" somehow objectively true for everyone? Or does it just mean "Don't believe X!", and hence is not really capable of being true or false? --(((Zack Martin)))^™ 10:51, 28 April 2011 (UTC)

That's not really what Yudkowsky means - what he is saying is, if we have a word that's causing us confusion, let's just replace the word with what we mean when we use it. It's not so much a philosophical argument as a technique for avoiding confusion in discussions.

As for the definition of "rational" - we can cut straight to the point very easily here. We don't need to even talk about whether there is some objective sense of "rational" or not. We can just apply the technique from the Taboo Your Words article (I'll reproduce the example here):

Albert: "A tree falling in a deserted forest makes a sound."

Barry: "A tree falling in a deserted forest does not make a sound."

vs.

Albert: "A tree falling in a deserted forest matches [membership test: this event generates acoustic vibrations]."

Barry: "A tree falling in a deserted forest does not match [membership test: this event generates auditory experiences]."

In our case, I am saying that we should believe things if they match [membership test: we think they are probably true]. You do not agree; you argue that we should believe things if they match [membership test: passes one of more of the three criteria you listed above]. To argue that one of these definitions may or may not be "objectively true" is a wrong question. Just because there's a word, that doesn't mean there's definition floating out there waiting to be found. Compare:

• "Is there an objective definition of rationality?"
• "Is there an objective definition of fuzzle?"

So instead of having a (rather silly) disagreement over whether this definition exists in reality, we should just acknowledge that we're after different things. I am after [membership test: we think they are probably true], and you are after [membership test: passes one or more of the three criteria you listed above]. This is somewhat problematic for your argument, since pretty much everyone else on this page is interested in [membership test: we think they are probably true]. Tetronian ^{you're clueless} 13:07, 28 April 2011 (UTC)

OK Tetronian, let me reword this dispute. I am urging people to follow one set of rules in deciding what to believe, you are urging people to follow another set of rules. These two rulesets, while they advise the same beliefs in some circumstances, advise contrary beliefs in other circumstances.

Why follow my rules? Well, I'd argue following my rules will make some people happier than following your rules will - maybe not everyone will be happier following them, maybe you won't be, but I think I will be and I think there will be many others who will be. I think, on a pragmatic level, my rules (proposed above) have just as many positive outcomes as the rules you propose, maybe even more than yours.

Why follow your rules? You suggest they are more likely to produce true beliefs. I am doubtful of that claim, I think both my and your rules will produce a similar quantity of true belief.

Besides, in trying to evaluate the rules, you have to form beliefs (whether about what set of belief-rules would make you most happy, or what set of belief-rules is most likely to produce truth), yet which rules will you follow in forming those beliefs? My rules, your rules, some other rules? Trying to evaluate belief-rules is inevitably circular, since one can only justify them in terms of beliefs which are subject to them already.

A good way of looking at it - we are looking at two competing formal systems, with different axioms and inference rules, and asking which one should we choose to govern our own thoughts. Yet any attempt to justify a set of inference rules or axioms must already assume some axiom rules or inference rules.

Taken to an extreme, this of course brings us back to radical skepticism (anyone can adopt whatever belief rules they want, and hence adopt whatever beliefs they want). Two proposed approaches to escape this:

1. The common denominator approach - although regarding some issues our competing belief-rule-systems will produce radically different outcomes, they do have certain commonalities (some beliefs one would hold regardless of which one one chooses to follow). Maybe, we can evaluate each system with respect to the common denominator between them, and maybe that will indicate which system to follow?
2. The mutual evaluation approach - let each evaluate the other, in the hope that maybe that will end up suggesting that we should accept one rather than the other? --(((Zack Martin)))^™ 11:17, 29 April 2011 (UTC)

First, the things I agree with: I like the way you framed the problem, and I like the way you defined your position and my own. I also agree that there is a circularity to arguing for a particular set of rules, even if I don't agree with the conclusions you draw from this.

What I don't agree with:

a) That your system is basically as accurate as mine. My reason for disagreeing with this is contained in here: once you try to "protect" a belief for some reason other than it being true, you potentially destroy your entire epistemology. The classic example is creationism - if you want to lie about where life came from, then you have to lie about a whole bunch of other things, and then ultimately you have to lie about what truth and evidence are. That's not a path I want to go down, so I simply refuse to "protect" beliefs from rational analysis - I give them all the same scrutiny. Regardless, I simply don't see how a system that says "I'll believe what's true except when doing so is harmful" can be as accurate as one that says "I'll always believe what's true." (And it certainly can't be more accurate.)

b) That we can use the mutual evaluation approach to come to a conclusion. Simply put, we have different goals. Though we probably agree about 90% of the time (as per the common denominator approach), this particular disagreement is, as far as I can tell, based on our different criteria for evaluating beliefs, as revealed when "rationality" was tabooed. We have different terminal values. I'm honestly not sure how one would resolve this dispute, if it is resolvable at all.

Additional nitpicks: While it's likely that your system will lead to greater happiness, this isn't necessarily the case - see choosing to be biased. (This might be the only thing that could potentially convince you to prefer my system over yours, but it's a pretty weak argument.) Tetronian ^{you're clueless} 20:28, 29 April 2011 (UTC)

OK, to put simply Yudkowsky's Dark Side Epistemeology argument - once you tell one lie, there is no limit to lying. However, look at my proposed principles. One says "Things we can't help but believe must be true", the second says "Given equal evidence, and no reasonable likelihood of that situation changing, one is rationally free to use non-evidential reasons to choose between the options".

Neither principle endorses "lying". Neither principle endores belief contrary to the evidence, only belief where (1) the evidence is insufficient to reach a conclusion (either no evidence at all, or equally balanced evidence each way) and (2) that situation is very unlikely to change. In particular (2) looks to not just practical limitations in our evidence-gathering ability (merely economic or technological limitations), but to more fundamental limitations (where we can say in principle no amount of money or technology is likely to bring us closer to the answer). This can't be compared to ignoring evidence, it is simply about how we choose to react to evidence's fundamental limitations.

Also, Yudkowsky's limitation seems to be a slippery slope - if you permit this, you'll permit everything. As such, his argument is open to the same criticisms that apply to all such arguments.

I think in some cases it can be right to even go against weak evidence, but not strong evidence. Consider a criminal case, where the prosecution has some case, but not a very strong one. Say there is plenty of circumstantial evidence, but no clincher. Is it rational to believe the accused is guilty? Well, an impartial observer would probably say, its not completely proven, but more likely than not he's guilty. But, suppose it was a close friend, family member, lover, etc., who was accused. Then it is natural you'd let your personal relationship colour your estimations of probability. Is this wrong? Well, judged by the standard that humans should be unfeeling thinking machines, it is wrong, but by a more human standard it seems the entirely proper consequence of natural human affection. But this is just about weak or moderate or merely suggestive evidence - if the evidence is strong enough, it should override such feelings. Yet Yudkowsky seems to imply that once you let non-evidential considerations overpower weak evidence, you are inevitably on the road to letting them overpower strong evidence too - but that seems to me to just be an unjustified slippery slope.

Mind you, although I do believe that when evidence is weak, it is justified to believe against it, that is not actually what the principles I have introduced say - they merely apply to cases when evidence is entirely missing or precisely equally balanced, not where it is present but only weakly so. But, if belief against weak contrary evidence is justifiable, then clearly belief against no evidence, or balanced evidence, is also justifiable.

About Yudkowsky's "Doublethink" - well, his invocation of Orwell suggests he is talking about deliberate going 100% against rationality - like Tertullian's supposed quip "I believe it because it is absurd". Whereas, I am not talking about going against any strong evidence, just absent evidence or precisely balanced evidence or weak evidence, especially when the lack of strong evidence is likely to be fundamental and rather permanent rather than a consequence of possibly temporary limitations. So, someone who follows the "doublethink" approach may well be unhappy as a result, but I don't see how that implies someone following my approach will be.

As to the suggestion we have different terminal values, we may well do so. But, I think possibly you are overestimating how different our values are. In any case, if we have reduced the conversation to values - well, if a materialist worldivew could be shown to be a consequence of subjective values, which no one need hold, then I would win against the viewpoint that sees materialism as a proven objective feature of reality, even if I don't actually convert any materialists into non-materialists in the process. --(((Zack Martin)))^™ 11:23, 30 April 2011 (UTC)

I'll try and keep this as concise and to-the-point as possible. Firstly, Dark Side Epistemology is not a slippery slope argument - it's a description of how people actually rationalize their beliefs. Furthermore, I am not accusing you of lying - what I am saying is that as soon as we protect a belief using extra-rational justifications, you are then going to have to explain away any rational reasons for disbelieving it. Hence, extra-rational privileging is bad. Also, your court example is wrong, because knowing a person is not irrelevant or forbidden evidence. Don't confuse what the legal system allows with the real definition of evidence.

As for your discussion of the limitations of evidence: I agree that some things are never going to be testable in practice, but I don't see how this licenses other ways of knowing. As you know, I'm fond of attaching probabilities to things; if we can't give one hypothesis a high probability and all of its competitors low probabilities because of our limitations, so be it. Though it may feel uncomfortable to think that a large number of hypotheses are all equally likely because we have little or no evidence, this still isn't grounds to use irrelevant information because this means that accuracy and truth are no longer our primary goals (more on this below). For the same reason, I don't believe that we should incorporate concepts like "can I live a sane life with this belief?" because we don't have a guarantee that the universe is arranged in a way that we can make sense of. (It may be so, but it isn't necessarily so.)

Regardless, it just doesn't make any sense at all to say something like "my system, which allows you to use information that is irrelevant what's true as evidence, is as accurate than yours, which only lets you use true and relevant information." Nor does it make sense to say (actual quote this time), "Mind you, although I do believe that when evidence is weak, it is justified to believe against it." This just doesn't make sense if accuracy is your primary goal, since it lets facts about you (e.g. your sanity, your well-being) influence your decision-making process when there is no reason for this to happen. And if accuracy isn't your primary goal, then you can't be as accurate as someone who does place accuracy as their primary goal.

Finally: "well, if a materialist worldivew could be shown to be a consequence of subjective values, which no one need hold, then I would win against the viewpoint that sees materialism as a proven objective feature of reality, even if I don't actually convert any materialists into non-materialists in the process." I have no idea what this means. Can you elaborate on this? Tetronian ^{you're clueless} 15:35, 1 May 2011 (UTC)

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┌────────────────────────────────────────────────────────────────────────────────────────────────────┘ OK, let's drop a couple of points of discussion at this point. Let's drop my whole "weak evidence vs. stronger non-evidence" case, the court room discussion, etc. I have responses to your points, but just in the interest of keeping the discussion more targeted. Likewise, let's forget I said "if a materialist worldview could be shown to be a consequence of subjective values, etc". Maybe we will come back to that later.

So let's just focus on my principle that "When there is no evidence either way, or equally balanced evidence either way, and that situation is highly unlikely to change, we can turn to non-evidential reasons to decide what to believe".

You say "as soon as we protect a belief using extra-rational justifications, you are then going to have to explain away any rational reasons for disbelieving it". However, if there are (1) no evidential reasons to believe/disbelieve it, and (2) it is highly unlikely any such reasons will ever eventuate, then what you have said is false. If (2) is true, then there are going to be no rational reasons for disbelieving it to explain away. And if there are, then (2) is false, and hence my principle didn't justify that belief to begin with.

You say "I don't see how this licenses other ways of knowing" - well, we are faced with a debate over "Should people do X?". One person objects "No they shouldn't, because Y,Z, bad consequences will result". Response: "Well, Y,Z could be bad consequences of doing some things similar to X, but given how precisely we've defined X, they are not bad consequences of X specifically". "Oh yes, you are right - but that still doesn't license anyone to do X, i.e. no one has provided any argument why they should do X, or should be allowed to do X?". "Well, maybe there is no argument why someone should do X, or should be allowed to do X, but there is no argument why they shouldn't do X, or shouldn't be allowed to do X, either..." And quite possibly there are arguments that they should, or should be allowed, to do X, depending on what we'll accept as arguments'.

"And if accuracy isn't your primary goal, then you can't be as accurate as someone who does place accuracy as their primary goal." Really? If someone has "believe that life exists in the Andromeda galaxy" as their first goal, and accuracy as their second, can they be as accurate as someone who has accuracy as their first goal? We could submit them to 50 hours of testing to determine whose belief-formation processes are more accurate. At the end of those tests, they'd both come out the same. Maybe if we repeated the same tests for once a week, over the next thousand years, they'd still come out the same. Maybe one day, when we've near-exhaustively explored the Andromeda galaxy, we might find a difference in accuracy between these two believers - but such an occurence may be millions of years away, or it may be never. So, likewise, someone who follows my principle, will be just as accurate in any testable matter as someone who doesn't, because the criteria (1) & (2) work to prevent the principle from producing a different outcome from your principles in any testable scenario. Of course, to be fair, you said that against my "weak evidence" case, and against my weak evidence case your argument may have more force. But as I've said, I've withdrawn it for now. --(((Zack Martin)))^™ 09:57, 2 May 2011 (UTC)

Let's start with the last paragraph first. Your Andromeda analogy is valid but not relevant here because this is a situation where we can't gather evidence and it's unlikely that we will ever be able to. So your analogy applies to the vast majority of possible disputes that we could have, but not this one. Since you seem to agree that extra-rational methods aren't as accurate as rational ones, this is a strong reason to use my system rather than yours, at least in this particular situation.

That said, we can move on to the fourth paragraph. In all honesty I am not arguing what is meant by "should people do X?", I am arguing the exact opposite. As I said above, I think that rationality is about laws, not about what would convince other people or what should or shouldn't be "allowed" in an organized debate. That is, all of the parts you put in italics in that paragraph, with the exception of "are," is what I am arguing against. To summarize: forget about "allowed", "should", "convince," and consequences" for the moment and just ask "what probabilities can I assign using the evidence?" That's all I'm after. (To clear up the confusion a little more: by "license" I meant "would be correct to use" - I didn't mean to frame things in terms of "arguments" or "convince," sorry if it sounded that way.)

As for the second paragraph: You are almost on the right track, but you erred when you said: "If (2) is true, then there are going to be no rational reasons for disbelieving it to explain away". The problem is that (2) states that it is unlikely that we will ever uncover evidence, not that it is impossible to uncover evidence. So even if (2) is true, there's a chance that we might find evidence, which is a reason not to preemptively believe using extra-rational means. I think the error came from forgetting that probability is in the mind, so saying "it's highly unlikely that we will cover evidence" really means, "it looks highly unlikely that we will uncover evidence given what I've seen so far." But there is always the possibility of a Black Swan swooping in in the form of unexpected evidence.

In conclusion: the precise definition of rationality is indeed relevant here because is unlikely that we will ever find evidence. I see rationality as being about what methods work the best, not about what methods we are "allowed" to use when we hit a stopping point. I believe this because extra-rational methods don't accurately help us figure out what is most likely true, which is my primary goal. As there is always a chance that we have not hit a permanent obstacle, we only increase the potential for inaccuracy by defaulting to other ways of knowing even when we get stuck using rational ways. Tetronian ^{you're clueless} 21:36, 2 May 2011 (UTC)

Andromeda analogy Why are you saying my Andromeda analogy isn't relevant? "Your Andromeda analogy is valid but not relevant here because this is a situation where we can't gather evidence and it's unlikely that we will ever be able to." Are you saying that idealism-materialism is a situation where we can never gather evidence, but life-in-Andromeda is not? I agree at a formal level, these two beliefs are different, but at a practical level they aren't. Claims about life in Andromeda galaxy are not testable now, and may not ever be testable. Maybe in centuries, millenia, millions of years, we might be able to test these claims. But a proposition which is untestable in practice isn't that different from one untestable in theory. Anyway, if an afterlife would support idealism vs. materialism, then we could test idealism by dying. You can object that shouldn't count as a test, but if dying isn't a valid test, arguably intergalactic travel is not a valid test either. At least with dying, we know it's going to happen - we have no idea if intergalactic travel is even possible, and if it is whether it will ever be achieved.

Afterlife as evidence for idealism: An afterlife supports but does not prove idealism, because if materialism is true an afterlife is very unlikely, although maybe not totally impossible. Materialist afterlifes might involve us living in a computer simulation, and our simulators transfering us to another simulation at our death, or advanced alien life somehow teleporting/cloning us to the mothership at death (like what Raelians believe). But most materialists would agree that these materialist afterlife scenarios are very unlikely, so that if materialism is true, an afterlife is very unlikely. Non-materialist views, like idealism or dualism, don't necessarily imply the existence of an afterlife, but since they don't privilege physical death in the way materialism does, they have no reason to suppose it should be the end of existence. Thus, if you found yourself in an afterlife, you'd be rationally justified in updating your probabilities away from materialism and towards an alternative theory like idealism or dualism.

Extra-rational methods as less accurate: You say that I "seem to agree that extra-rational methods aren't as accurate as rational ones". Well, there are many different types of extra-rational methods, some broader in scope, some narrower. If the scope is made sufficiently tight, there will be no observable difference in practice comparing the use of that extra-rational method to a purely rational one.

Should people do X? I think you are misunderstanding my use of "should". When I say "should", I'm not talking about whether people should be legally required to do something, or punished for not doing it, or physically compelled to do it. When I say "should", I mean rationally should, i.e. they should if they want to be rational. When you ask "what probabilities can I assign using the evidence?" - well, I can assign whatever probabilities I like! What you mean to say, is which probability assignments would be rational? Is there a single rational, or a single most rational, probability assignment, or a range of possible probability assignments, all equally rational? And if there is such a range of equally rational probability assignments, I could use non-rational means to choose which one I will adopt without being irrational.

Unlikelihood to find new evidence You say "(2) states that it is unlikely that we will ever uncover evidence, not that it is impossible to uncover evidence". I say not just unlikely, but highly unlikely. High unlikely is a fair bit stronger than just unlikely, but not quite as strong as impossible. I admit the principle is slightly vague in terms of how much unlikelihood (2) requires. One can actually construct ever stricter versions of my principle, each of which makes (2) stronger. Now, the stronger a version of (2) one uses, the less likelihood following my principle will cause one to commit an error in practice. There will come a point, with (2) made sufficiently strong, that any error due to following my principle will be drowned out by the error due to unrelated causes. The question is, if I make (2) stronger, does there come a point at which (2) becomes too strong for it to apply to the idealism-materialism question? Maybe there does, but I'm not sure if there is where exactly that point would be.

Optimality vs permissibility You say "I see rationality as being about what methods work the best, not about what methods we are 'allowed' to use". Two models of rationality: (1) in every situation, there will be one belief (and one belief only) which is rational, or most rational, to believe; (2) in a situation, there will be a range of multiple beliefs which are prohibited by rationality, and a range of multiple beliefs which are permitted by it. So your model of rationality assumes a single maximum in rationality, whereas there is an alternative model which believes that, given the same evidence, there may be multiple beliefs that are equally rational. --(((Zack Martin)))^™ 09:21, 3 May 2011 (UTC)

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By the consequences of your argument, there is no "I won't be able to function in life without believing X" for any of the cases of beliefs that apply to you. Functionally, I could operate in life and not be dysfunction by assuming that your posts are being made by a computer program... or even that they're cosmic radiation causing massive cascades of bit errors. These beliefs can be regarded all you want as "irrational", but they do not warrant me going to the asylum, nor do they prevent me from coping with ordinary life at all. In fact, while you claim solipsism is unjustified because it would make a person incapable of coping with ordinary life, no such actual consequence follows as a result. John Nash believed he had a college roommate for years who objectively it was known not to have actually existed, yet he was able to cope with ordinary life. By your claims, John Nash was justified in his beliefs only so long as he was able to cope with ordinary life? --Eira ^{OMTG! _{The Goat be Praised.}} 20:23, 26 April 2011 (UTC)

Eira, I am not sure you are understanding me. It sounds like you think I see these principles as justifying my religious views, but I am not making that claim. I am simply making the claim they justify the rejection of solipsism. Clearly, people can and do deny all my religious claims, or any religious claims, and still retain their sanity. But belief in solipsism or Last Thursdayism, that is a different kettle of fish. I do see these principles as supporting my religious views indirectly, but it is entirely possible for someone to accept them, yet still reject my religious claims, because my religious claims are not directly entailed by these principles.

As to solipsism, you are suggesting you could still function in life and believe my mind does not exist. I agree completely, you could. Solipsism is equivalent to the claim "Everyone but me is a philosophical zombie" - I think it is impossible to live with that belief. But, if I believed that Barack Obama was a philosophical zombie, well that belief is unlikely to have much negative impact on my life at all. So let us distinguish three cases - (1) "full" solipsism - everyone except me is a philosophical zombie; (2) "partial" solipsism - some, but not all, people other than me are philosophical zombies; (3) non-solipsism: there are no philsophical zombies. I think my principles justify disbelief in (1), but they don't justify disbelief in many forms of (2). "Partial solipsism" is a broad continuum - at one extreme, is the claim almost everyone other than me is a p-zombie, which may well be a belief impossible to sanely hold; whereas, the belief that only a small minority of people are p-zombies, is much easier to sanely hold.

In terms of your reference to John Nash, you are reversing the direction of implication - I am saying if a belief is impossible to believe, we are rationally justified in disbelieving it by that fact alone; I am not saying that if a belief is possible to believe, we are rationally justified in believing it. I am saying P implies Q, you are talking about Q implies P.

Although, speaking of John Nash - it is interesting how psychotic people can believe all kinds of strange things, yet I have never heard of even an extremely psychotic person believing in solipsism or Last Thursdayism. Probably very few, or even none, do. (I think some known psychotic delusions - e.g. Capgras delusion - are similar to solipsism, but still not the same - a sufferer of Capgras believes their family has been replaced by impostors, but those impostors are not generally believed to be people without minds, just different people with different minds, i.e. impostors). --(((Zack Martin)))^™ 10:38, 28 April 2011 (UTC)

I am saying if a belief is impossible to believe, we are rationally justified in disbelieving it by that fact alone; Except that this does not exclude your position of full solipsism. To argue that you've never seen someone like that is an argument from lack of experience, and to argue that you don't see how someone could actually operate that way is an argument from lack of imagination. I perfectly well see and understand how someone could operate with the belief of solipsism... I for one have an incredibly good mind for things, and also a nearly eidetic memory... I do not find it impossible that my mind could just be making all this shit up, and I am fooling myself. Namely, the evidence does not exclude this belief... the typical reason for rejection of solipsism is the assertion of arrogance. And honestly? While I agree that it is arrogant, my mental skillz often crash against other people, and they call me arrogance simply for being honest.

So, to point, solipsism is an assumption that it is impossible to believe... I just find that the philosophical zombies in my imagination like to argue the matter with me anytime I bring it up, and I haven't enjoyed such internal dialog recently, so I don't typically bring it up with myself. But you seem like a special philosophical zombie for me debate with... I must have been getting philosophically bored and wanted some sort of idiot opponent for me to argue against and thoroughly trounce on a regular basis... --Eira ^{OMTG! _{The Goat be Praised.}} 01:53, 30 April 2011 (UTC)

Eira, obviously my argument is based on the assumption that solipsism is impossible for anyone to really believe. If you don't accept that assumption, then obviously my argument doesn't work.

I don't think you are actually saying you do believe in solipsism, just that you can imagine yourself believing in it, and hence it seems to you possible for you to believe it even though you don't.

Personally, I don't find your own account of your powers of your imagination decisive - I can't test your own claims of the powers of your imagination, I just have to take your word for it.

But, if you can point to a well-documented case of a person who seriously believes and defends and argues for solipsism, and is otherwise not obviously insane, then I will admit defeat. --(((Zack Martin)))^™ 10:56, 30 April 2011 (UTC)

A different approach

I'd like to take a slightly different tack here. Since it's been well-established above that none of the arguments in this essay are falsifiable, what we are really arguing about are the logical implications of what we have observed. I fail to see how "things exist in a state of limbo when no one is looking at them" is a logical implication of our knowledge of the universe. The only case in which this is slightly applicable is if you wanted to defend the Copenhagen interpretation, but even in the case of QM many of the "subjective" elements are misunderstandings.^{This is a very interesting paper, by the way.} But from your essay it's clear that you are not defending the Copenhagen interpretation, you are just using it as an analogy. That said, the sort of "superposition" of reality you described just does not follow from what's observed. For example, take the starlight problem - how is it that light from faraway stars just happened to be visible when we started observing it even though these stars are billions of light years away? This makes sense under materialism, because the stars existed for billions of years and the light has been traveling continuously from here to there since then. Under your system, you'd have to invent some kind of explanation for why this is so. The starlight problem is not the only relevant piece of evidence - basically any continuous process that was going on when human beings evolved is applicable here. As a result, you would have to invent explanations to cover every such phenomenon, which would essentially be adding dozens of ad hoc burdensome details to your hypothesis. Thus, the idea that reality is in some kind of limbo is clearly not the logical implication of what's observed.

When you reply, please don't bring up the simulation argument or the argument from multiple pasts - for the moment let's focus only on the argument from idealism. Also, I've made it clear in the section above that I, along with most if not all of the other RWians on this page, are interested in believing things only if they look like they are probably true. This argument follows that definition. If your reply requires you to use a different definition of truth or rationality, then there isn't much of a point in replying since we will just be talking past each other. Tetronian ^{you're clueless} 13:42, 28 April 2011 (UTC)

Kind of reminds me of that point in What the Bleep where she turns away from a child bouncing a basket ball and suddenly, because she isn't looking at it, the basketball is in all places at once... it's the abuses of those sorts of quantum mechanical concepts that makes me think pop science should be banned from ever discussing it. ADK^{...I'll assassinate your operating system!} 13:50, 28 April 2011 (UTC)

To start with, addressing the Copenhagen interpretation - obviously it is just an interpretation of QM, not QM itself; there are other perfectly valid alternatives, like many worlds or hidden variables - indeed, hidden variables is obviously what the author of that paper prefers, although his case is more that it is wrong to dismiss it from being a genuine possibility, then that he has any definite evidence for it versus the other theories. I rely on it for two reasons (1) idealist thought is difficult for someone used to materialist thought to grasp, but if they can understand Copenhagen, then that can help them to analogically understand my position and (2) if Copenhagen is a coherent/plausible position, and my position is similar to Copenhagen, then possibly that may imply my own position is coherent/plausible. I don't assume Copenhagen is true, and I don't claim Copenhagen if true would imply my position. As the author notes, Copenhagen comes in different variants, some of which are what he calls more anthromorphic - and those versions of Copenhagen are most like my own viewpoint, but even they aren't the same as it, and there are other variants of Cophenhagen that are less "anthromorphic" (the author suggests the less anthromorphic versions are more popular, and he may well be right.)

I think there are a lot of people who don't know alot about QM, and as a result tend to confuse one interpretation of QM - among "New Agey" types, most commonly one of the more "anthromorphic" versions of Copenhagen; among the more "rationalist", it seems to be many worlds, or a less anthromorphic version of Copenhagen, or an objective collapse theory - with QM itself. And the New Agey ones are the sorts of people that Armondikov's mentioning of What the Bleep is referring to. I am not an expert at QM by any means, but I think at least I've demonstrated an understanding of the existence of multiple competing interpretations of it, and the fact that those interpretations are distinct from the theory itself.

That said, the sort of "superposition" of reality you described just does not follow from what's observed Well, let me clarify my point - I don't claim idealism follows from our observations. I claim it is compatible with it, but does not follow from it. I also agree that materialism is compatible with our observations, but I don't agree with claims that materialism follows from our observations. My view is that both are compatible, neither follows, and hence observations can't be used to decide between. So, either we should be agnostic, and not choose between them, or else look for some other consideration than observations to pick between them.

how is it that light from faraway stars just happened to be visible when we started observing it even though these stars are billions of light years away Well, all chains of explanation have to end somewhere. A materialist might say, well, its a consequence of the Big Bang and the laws of physics. But then, we can still ask, why the laws of physics? why was there a Big Bang? It all ends with That's just how it is, or else Goddit, which doesn't really help us because the answer to why God? is also That's just how it is. I might put the Just so somewhere else from where you would, but its a Just so all the same.

Materialists believe that the material universe is governed by laws of nature. I think a good way to see the laws of nature is in terms of a perfect law, which is the Kolmogorov compression of a precise straightforward description of the universe (such as a string listing properties of every particle, or whatever the fundamental constituents of material reality are, at every point in spacetime), which is the only precisely accurate and precisely succinct and simplest possible law of nature, and a series of imperfect human-created approximations to that unknowable perfect law. (Eira doesn't want me to say Kolmogorov compression, but I think it is the best term - she would rather I say ideal compression or perfect compression, but I don't think those terms make it sufficiently clear that I am looking at things from the viewpoint of computability theory - in any case, if you understand Kolmogorov complexity, I simply mean the program the length of which is the Kolmogorov complexity.)

I can apply the same model to idealism, except instead of the perfect law being based on a precise description of every particle (or whatnot), it is instead based on a precise description of every qualia of every mind in the universe. I think we can subdivide qualia into atomic constituents, and provide (theoretically speaking) a precise description of them, which can then be subjected to Kolmogorov compression.

So, a materialist can provide an answer to Why starlight? which ultimately boils down to The laws of nature say so. Well, an idealist can provide the same answer, although they differ on what the fundamental laws are actually about. Now, maybe a materialist can provide a more detailed explanation than the idealist can, but maybe that's just because more work has been done at trying to understand the world from a materialist viewpoint than an idealist one? Both are seeking imperfect human approximations to an unknowable perfect law, its just that more effort has been spent on building approximations to a materialist law than work has been spent on building approximations to an idealist one.

And I think the two sets of explanations, materialist and idealist, are fundamentally inter-transformable in principle. If I have a theory which precisely states the position of every particle (or whatnot) in the history of the universe, I can infer (in principle) from that theory every mind and experience in that universe, and thus produce an idealist law from the materialist law. Likewise, considering a universe produced by an idealist law, I can identify the materialist law (or laws), which produce universes which contain the same minds/experiences.

Of course, when I say I can, I mean that from a perspective of (non-constructivist) mathematical principle I can, obviously I actually can't in practice. But, at a more practical level, I can likewise take a materialist approximation and convert it to an idealist approximation, or vice versa, but it may get more complex in the process. For example, from a materialist theory, I can infer the mental consequences, and thus I can transform the materialist theory into an idealist one which states that minds will have those experiences. I think the reverse process, from idealist theory to materialist theory, is also possible.

My point is, any questions of the form How do you explain observation X?, well an idealist can explain them about as well as, and about as poorly as, a materialist can.

And I guess my explanation above will not satisfy many materialists. But it is simply impossible to give an account of idealism which will satisfy someone who has already decided upon materialist assumptions.

If your reply requires you to use a different definition of truth or rationality, then there isn't much of a point in replying since we will just be talking past each other. Well, I should explain that our difference in theories of rationality is rather limited. I think we are basically the same in our approach to rationality except for the principles I outlined above. And I think I am rather limited in the way I use them. My first principle is basically "if we have no choice but to believe it, it must be true". I don't infer idealism from that principle, obviously we have a choice between idealism, materialism, dualism, and maybe even some other theories too. I simply use it to infer the falsehood of sceptical hypothesises like solipsism or Last Thursdayism or so on. Now, if you don't accept that principle, fair enough, but then you need to find some other principle to rationally justify your rejection of solipsism, Last Thursdayism, etc. But really, this is mostly separate from the issue of idealism.

My second principle is basically "if A and B have equal evidence, and no new evidence is likely to arise, we are rationally justified in using non-evidential reasons to choose between A and B". Now, the way I use this principle is as follows: (1) firstly I argue the evidence is insufficient to decide between idealism and materialism, and that situation is unlikely to change, then (2) I introduce non-evidential reasons to prefer idealism to materialism. Now, if you don't accept this proposed principle of reason, then you won't follow my argument in (2). But, my argument in (1) is independent of this principle. And if you accept my argument in (1), but reject this principle, then what you are left with is neither materialism nor idealism, but agnosticism with respect to the idealism-materialism question. --(((Zack Martin)))^™ 10:51, 30 April 2011 (UTC)

I'll try to keep this as concise as possible. First, you said "I don't claim idealism follows from our observations. I claim it is compatible with it." The problem here is that we are not talking about what you are "allowed" to believe given the evidence, since that's a poor standard. A believer in homeopathy could say, "Well, I'm still allowed to believe because there isn't a proof that I'm wrong!" So it's clear that what we want is what is most probable given the evidence and not what am I still "allowed" to believe given the evidence. If you disagree with this, we can basically end the argument right here because we're not going to get any further.

The reason I think that materialism is more likely given the evidence has nothing to do with chains of explanation - in fact, that is completely irrelevant to the argument. Since no one has really cracked the First Cause problem (or figured out that it is a wrong question, which I think is more probable), it's not a good argument no matter how it's used. I understand that you were using it to show how our positions are equivalent, and in a certain sense that is indeed true, but that's not really relevant to my argument.

The crux of my argument is this: materialism postulates that stuff exists independently of minds. Therefore, materialists do not anticipate that the universe will look like it was generated as we explored it (like, for example, some poorly coded video game that generates new terrain when you move into a previously unvisited area). Since a universe that looks like it doesn't obey fixed, natural laws would be strong evidence for idealism, it follows that observing the opposite must be at least weak evidence 'for materialism. The bottom line is this: you can't point to the fact that our universe looks like it obeys fixed, natural laws and say that this doesn't tell us anything. Note that this has nothing to do with the fact that "more time has been spent looking for materialist explanations than idealist ones" - it's a consequence of definitions of the two theories, not of research paradigms.

As for solipsism et al. - I don't have a rigorous rejection of every variation of these, but some of them are pretty absurd to begin with. "We could be living in the Matrix" arguments don't bother me because the idea that reality might have some deeper levels to it doesn't undermine materialism/reductionism - it just means that there are more parts to reality that may or may not have their own rules, and we can figure them out when we get there. Some of the formulations of solipsism are nonsensical because they seem to imply that it's my conscious mind that is creating reality. But this is obviously untrue because I have the ability to be surprised by experimental results. Thus, whatever is creating reality isn't a part of my conscious thought-process, so while it may be a part of "me" on some deeper level, it definitely isn't on this level, which makes the situation isomorphic to the Matrix scenario discussed above. I don't have a rigorous rejection of Last Thursdayism and this paragraph is already too long so I won't elaborate. Ultimately, saying, "well, you can't reject <worrisome idea> is not an argument to prefer one standard over another - in general it's not good to a priori exclude <worrisome idea> just because you don't like it. (And you certainly can't go one to use this as a standard to compare your epistemology to other peoples' epistemologies!). Tetronian ^{you're clueless} 14:00, 1 May 2011 (UTC)

┌────────────────────────────────────────────────────────────────────────────────────────────────────┘ Apologies for my verbosity, it is my fatal flaw. I will try to be briefer, but I probably will not do that good a job of it.

When I say "idealism is compatible with our observations", I am simply saying our observations don't exclude it. They don't exclude materialism either. More than just not excluding one or the other, I don't think they give any indication one is more likely to be true than the other.

You say "what we want is what is most probable given the evidence". My principle states, if several things are equally likely given the evidence (and that equal likelihood may be no different than a uniform prior, i.e. reflecting no relevant evidence available), and that situation is highly unlikely to change (we are very unlikely to get any further evidence than what, if anything, we already have), and if we have sufficently strong non-evidential reasons to prefer one belief to another, then we should believe what those non-evidential reasons prefer. You and me, we want differ things, although a lot of the time we'll want the same thing in practice.

My invocation of "First Cause" was simply in response of the request to a request for an explanation. Much as a materialist atheist might say that asking for an explanation for the Big Bang is to ask for a question that doesn't have an answer (and maybe doesn't need one), to ask an idealist why do minds exist, and why do they experience what they do? is to ask for a question that doesn't have an answer, and maybe doesn't need one. Now an idealist can give a partial answer - minds have experiences X, because pattern P exists in the experiences of minds, and experiences X is consistent with/implied by pattern P. But an idealist must reach a point at which they can give no further explanation - yet a materialist will inevitably reach the same point too. Why pattern P and not some other pattern? One can justify some patterns-in-experience as subpatterns of larger patterns, but at some point one must end with a pattern that just is, just as the Big Bang just is.

A more fundamental way to put this. Ask a materialist Why is materialism true rather than some other theory, like idealism?. They'll answer That's just the way reality is, there's nothing more that can be said than that. Ask an idealist why is idealism true, you'll get the same answer. (Note I am asking why is the theory true, not why should we believe the theory is true).

You say that if idealism is true, "the universe will look like it was generated as we explored it (like, for example, some poorly coded video game that generates new terrain when you move into a previously unvisited area)". I don't agree with that implication, I don't see how it follows from idealism.

As I've already argued with Eira, I don't agree that "a universe that looks like it doesn't obey fixed, natural laws would be strong evidence for idealism". I'm not even sure what it means to say that a universe doesn't obey "fixed, natural laws". Quite possibly there exist other universes, which obey different laws from this one, but I don't see how the fact they are different makes them any less fixed or natural. And I don't see how the laws of nature being organized any particular way implies anything about idealism-vs-materialism. To an idealist, different laws imply minds having differing experiences, so a difference in laws between different universes just means that minds in those universes have different experiences from those in others.

I think the argument against solipsism/Last Thursdayism boils down to this. We both agree they should be rejected. We both agree the rejection of them is rational. We just disagree on what rule of rationality makes our rejection of them rational. I have put forward a particular rule I see as rationally justifying my rejection of them. You don't agree that my rule is a rational rule, you think it is an irrational one. Well, a challenge then for you is to provide an alternative rule(s) of rationality which justifies your rejection of them. You've made a start at that, but I think you need to expand on it. --(((Zack Martin)))^™ 10:34, 2 May 2011 (UTC)

Trying an attack on an equal philosophical level

Sorry if I use arguments that have been brought up before I haven't yet read all of the above comments. Just call me an idiot give me a link and I'll write were the actual discussion is if this is the case.
Now, it has been mentioned before that you're actually attacking science (or the bipolar logic of it's methods, to defuse it a little) and while I and most scientist will share the view that we can never be completely certain, it's seems silly too do so because it's practical implications are beneficial to us. (Btw, I refuse the typical scientist saying philosophy to be "head mastrubation", as he wouldn't be able to say something like this in a free society we both probably live in.) Let's just take it one level more abstract than science and make this a philosophical discussion - I will use the same method as you did: I will simply attack your premises.
Idealism: The problem of general idealism is that it is unprovable. Neither philosophy nor science can prove it, it comes with the notion that if you try to observe things generally exist - therfor trying to prove something you have to observe, record or something else, therefor things exist. How probable is it to assume something like this when all that we actually do have observed only exist for certain because we observed it? I isn't, it's a great piss on Occam's razor - which is only the teaching that terms with less variables are more probable to be true then terms with more variables. And a general question: Is there a camera in your fridge (would a camera suffice for "a mind abserving"?)? Because if not how are your drinks and your food kept cold in a state of indeterminacy? Have they been kept in such a state? Do physical laws still apply in such a state? Or are there other laws implying in such a state? (And if so why assume such a state exists if it would ad another variable to the term?) How come your drinks do have exactly the temperature they should have according to the setting of your fridge (they would have to have the same laws applied to them as in the real world in indeterminacy, or by opening the fridge the random onset of a temperature would a occure and magically set itself by probability? A probability btw, that would decrease everytime somebody opens a fridge.)? How come bacteria are changing something that does neither exist nor doesn't exist, how can in such a state change happen (Insert question discription from up there down here again)?
Idealism is improbable, it in is just like the assumption "God did it!" an escape hatch not to accept reality. A reality with which the Western culture is struggling for thousands of years. First we thought the mind was key to everything, and that with our own mind we can make up everything. The thought of an all-knowing, all-mighty god created the illsuion that we are not cappable of fully understanding the universe but that there is a being that can. Culture changes and as such the Renaissance and the Enlightenment happend, the thought that we can not understand everything in the universe got carved into stone but we now had the key of rationality - the assumption that there are certain laws that are the mechanics (the study not the profession) of everything that is and could be - to understand something. And for those that refuse either the outcomes of such findings or the very basics of such findings the thought that things aren't absolute, that there's still another option is important to feel comfortable. I don't want to take that away from anybody, but if you use logical reasoning in your thinking process you should play by these rules, idealism is possible but not provable and therefor goes against such rules.
Your "penetration" of idealism on a possible state in which evolution did not happen have a logical problem: If there was time in the indeterminacy before there were minds, how come anything has ever evolved? How come we exist if there was nothing before us to make that which we came from in existing? The notion that we have just appeared is funny, even more ridiculous than the thought that god created everything in whatever time frame. And even if there was a god, evolution would then be possible again because there actually was an observer. If everything that is (logical value: true) is set in a time and space continuum and everything that is isn't (logical value: false) how can there be another state (logical value: true and false at the same time). Even if something doesn't exist, if it still exists at the same time it is subject to what we experience as natural laws (gravity, termodynamics, evolution). So if an biological being exists in such a state it has to change while it stays the same. So while changing in stays the same? Or is rooted in both the state of existence and state of non-existence of the same? If it is in no state of such, the object would still be in both states, because not being in one of them means being in the other. Either an object is black or it is non-black, either an object exists or it doesn't. If an object would not have a physical appearance of any measurable kind, it doesn't have one and therefor we can assume it doesn't exist because anything else would go against our definition of existing (wouldn't it go against your's too? If not please explain).
Computer simulation: I actually loled at this. Of course it's possible that we simply live in an computer simulation. And if we can call ourselves Neo and get out of it that's fine, but again using Occam's razor we would have to take a wide range of variables to be true. Another explaination is that in such a case the definition of natural law would still stand untouched (a law apllying in all places at all times in a specific universe). Even if the universe was simulated there would still be such laws (we might then call them artificial laws but whatever), because the laws the system programmer has written in there still apply at every given moment and at every given time in our simulated sub-universe, so if the programmer now said "Hey let's have a law called evolution!" that law would still apply in our sub-universe. Of course not in the real one then, but we wouldn't be able to reach it anyway, and the laws of such a universe would only apply to the system that is running it - not to us. Therefor we are again on one level with our laws they then matter again as much us everything else in our simulated little world. And btw, if the laws of a different universe were so different what tells you you are capable of understanding the needs and wishes of such other beings, heck I'm sure there are thousands of physicists out there that would rather run a full simulation of the universe on a super computer than play Sims (heck, I'd rather do that).
Multiple Pasts: No, if two universes merged it would practicly create a new universe in which some of the laws of one universe occur and some of the other universe. Whatever the evidence of the new universe then says is the past of such a universe. Also, the notion of such an occurence is not an argument against the probability of evolution but for it, as the probability would grow from 1/n to 2/n (with n being the number of all theories and logical explanations). Using a metaphor: If we research the history of a state (state, I wanna stress that here because of the fundamental laws that stay the same) in history and that state was mashed up of two states, everything before that mashing up would not be the history of that state but the history of the states that existed before this one, as equal as the future of such states would have been the new state. What matters here is the stability of the laws not the geography of such state/universe.
Generalities: You speak of evolution having occured, but it still does. There are measurable changes in humans with each generation, for example it seems to be that young males have less chest hair then older males (if you don't believe me go swimming and take a good look). Why is that? We have been able in the last century to cloth ourselves warmer, as the human body wants to survive and therefor doesn't want to waste energy. So what can you? Stop groing hair where you don't need it! =lower hairy-ness of the human body as a whole. (As women often shave everything off that isn't on the top of their head, it's quite impossible to make an assumption there - asking: "Do you shave less then your mother?" probably only works if you have a scientific study.) The same problem with hairy-ness occurs on an interracial scale. (East) Asians have less hair then other races, this explaines itself by making the assumption that humans have developed from different species of homos (we all know in the context which kind of homo I mean). If such homos lived for a long time in different environments their scale of hairy-ness would differ, so if all races (I think everything is rootable in White, Black and East Asian - but I could be wrong) came from different come from different kind of homos, the homos that walked around in East Asia probably were less hairy then for example the ones of Europe - which again makes sense in context of regional climate. You probably know that many men all around the world have the hots for what they consider exotic women, one could assume this comes from a wish to have an adventure or an complete lack of xenophobia on the male part. But it makes sense in evolutionary context and existed before our mulitculturalism arrived. So what's up with that? If we can agree that a race shares a certain gene pool, and the wider the gene pool is the higher the probability that the children may survive, so by mixing up with other races the probability of having successful genes get's higher, and therefor the probability of children surviving a change in the environment. Something equally is applicable in females but much less extensive because the need of women is that their children may survive so what counts first is a father that is able to keep the children alive - this results in East Asia to blond tall men and women being considered "exotic" while we whites try to get as brown as possible and built a whole freaking industry around it - basically people lying on the beach for weeks, going to the solarium and loving summer way more then other cultures is an expression of the evolutionary drive. But evoltution is not only in biology it's a natural law everywhere competition exists: market economies are basically survival arenas of companies, which by bringing out new product secure them spreading there genes (getting more market share) and their further existing (profit). Different ideologies are in constant competition to spread and secure themselves, states are in constant competition against each other and have taken the step to cooperation a long time ago, religions, music no matter if commercial or not, cultures, languages, copyright agreements, wikis, writing systems, scientific branches, universities and so on. --UHM, Your favorite pain in the ass! 17:07, 30 April 2011 (UTC)

Idealism The problem of general idealism is that it is unprovable I mostly agree - it is maybe not absolutely impossible to prove, but certainly very difficult to do so. However, surely the same applies to materialism?

As to your point it comes with the notion that if you try to observe things generally exist, and your point about Ockham's razor, I'm not completely sure what you are saying - could you rephrase?

Is there a camera in your fridge (would a camera suffice for "a mind abserving"?)? Because if not how are your drinks and your food kept cold in a state of indeterminacy? A camera is not a mind. A camera by itself does not count as a mind observing, although it could be the means of a mind observing if someone viewed the photographs/video it took. How are they kept cold in their indeterminacy? Well, the indeterminacy is not absolute, only partial. Certainly the contents of the fridge is cold, but precisely how cold? How precisely can we measure its temperature - down to milikelvins, microkelvins, nanokelvins? In normal circumstances, we aren't measure its temperature that precisely. Yet many materialists will hold that its temperature exists with such precision, even though we will never know what its temperature was to that precision. As an idealist, I say it is cold, but its precise temperature is indeterminate because no one knows it with such precision, nor will they ever. Now, a fridge with some extremely precise thermometer in it, such a fridge would have less indeterminancy as to its temperature, provided a mind reads the thermometer.

Do physical laws still apply in such a state? To put it simply, yes. Although, please read my response to Tetronian above about different senses of law, idealist vs. materialist.

How come your drinks do have exactly the temperature they should have according to the setting of your fridge The setting of the fridge does not directly imply the temperature of the contents. It only approximately implies it (due to the thermostat control mechanism, the actual temperature will tend to oscillate anyway.) As well as the oscillation due to a thermostat, the thermostat itself will not be precise - it only measures temperature at the sensor, but the temperature in other parts of the fridge will be different (although not widely dissimilar) - and even at that sensor, its behaviour is consistent at say the kelvin scale, but probably isn't at the nanokelvin scale. As I've said, materialism basically commits you to the belief the fridge contents has a precise temperature, down to the femtokelvins, even though no one will ever know it (except maybe for the extremely rare fridge which is filled with advanced measuring equipment - and even then, femtokelvins is probably too precise to measure)... Whereas, idealism says the fridge's temperature does not exist with such precision, it is an indeterminate state of many possible temperatures, but not of every possible temperature - it is an indeterminate state of every possible temperature consistent with our observations, but not temperatures inconsistent with them.

How come bacteria are changing something that does neither exist nor doesn't exist Bacteria are present, but it is indeterminate as to precisely how many individual bacteria there are, or precisely where each of them are. If we observe the bacteria in more detail, e.g. with a microscope, then they become more determinate as our knowledge of them increases.

Idealism is improbable What makes it improbable? I would say its inherent probability is the same as materialism. I haven't seen any evidence to the contrary. How does one even begin to compute these probabilities, anyway?

that with our own mind we can make up everything I don't believe that. Although I do believe all reality is a product of our minds, we have yet very limited control over reality, because we have very limited control over our minds.

the assumption that there are certain laws that are the mechanics (the study not the profession) of everything that is and could be Well, as I've said in my discussion with Tetronian above, I agree there are such laws, but are they laws of matter or laws of mind? In my view, the fundamental laws of reality are laws of mind; there are many fundamental laws of matter compatible with those laws of mind, but no single such law is the right one, since countless configurations of matter can produce the exact same configuration of mind.

if you use logical reasoning in your thinking process you should play by these rules, idealism is possible but not provable and therefor goes against such rules Materialism is possible but not provable, so it goes against those same rules? That is not an argument for materialism, it is an argument for agnosticism with respect to the idealism-materialism issue.

If there was time in the indeterminacy before there were minds, how come anything has ever evolved? There was no time before minds. Time begins when mind begins. So nothing evolved, because there was no time in which evolution could have taken place.

How come we exist if there was nothing before us to make that which we came from in existing? Your views has that problem just as much as mine. What caused the Big Bang? At some point, we have to say It's just so, and no further reasons are available. Or else we say Goddit, which doesn't really help us, because then we ask Why God? and get back the same answer. So, both our views assume something existing without explanation - you would apply that to a materialist universe as a whole; I apply that to minds. You think minds require explanation, but if they do, why doesn't the Big Bang require explanation as well? Why does something exist instead of nothing? It's just so!

The notion that we have just appeared is funny, even more ridiculous than the thought that god created everything in whatever time frame How is it any more ridiculous than the claim that the universe just appeared in the Big Bang?

And even if there was a god, evolution would then be possible again because there actually was an observer. I agree with that, but it requires (1) a god to exist, (2) that god to be interested to watch evolution over aeons. Personally, I believe in a god, but I don't think she could really be bothered. But, if you want to believe in something like God as conceived by Berkeley, then yes evolution could happen then. But I don't share that belief.

If everything that is (logical value: true) is set in a time and space continuum and everything that is isn't (logical value: false) how can there be another state (logical value: true and false at the same time) This is possible if the time and space continuum of which you speak is not the fundamental reality, but something else is. Multiple configurations of that spacetime continuum could all equate to the same fundamental reality, in which case we can't say any such equating continuum in particular is true, only that all of them are simultaneously true (as contradictory as they are), and the other configurations are false. So, I'm not ultimately a dialetheist_{although I have read some of Graham Priest's work, and I find it fascinating}, although on the surface maybe I appear to be one.

Computer simulation: using Occam's razor we would have to take a wide range of variables to be true I have some uncertainty about Ockham's razor. It seems to admit many competing formulations, and its not clear which one is the right one. But if we can't work out which one is right, maybe none of them are, and hence Ockham's razor itself is wrong? Anyway, Ockham's razor, in its original formulation, was do not multiply entities unnecessarily. It is ambiguous, though, as to what counts as entity multiplication. Is that just asserting further entities to exist? Or does it also include asserting them not to exist? If it is purely positive, then Ockham's razor tells us to prefer the non-simulation case. But if it is both positive and negative, then it tells us to prefer neither case, since the simulation case multiplies assertions of existence, the non-simulation case multiples just as much assertions of non-existence.

Therefor we are again on one level with our laws they then matter again as much us everything else in our simulated little world Well, if to exist was to be simulated, the universe governed by laws would only exist in those parts of the simulation actually executed. If I go back to my point, if you start the simulation at Big Bang, evolution may well happen... if you start the simulation 1 million years ago, then no Big Bang, and most evolution wouldn't happen either. Also, you might restrict your simulation to just one planet in full detail, and more distant parts of the universe simulate in less detail - in which case, that one planet exists more fully than the rest of the universe.

And btw, if the laws of a different universe were so different what tells you you are capable of understanding the needs and wishes of such other beings, heck I'm sure there are thousands of physicists out there that would rather run a full simulation of the universe on a super computer than play Sims (heck, I'd rather do that). Indeed, on the assumption our simulators are like us, we can guess at their motives and possible behaviours. You are right that assumption may not be true, in which case we can know nothing about their motives and possible behaviours. The conclusion is, if this is a simulation, since we don't know their motives, we don't know if the distant past, or distant space, is simulated to the same level of detail as our here planet is. If our universe was created by a 15 year old girl addicted to causing relationship drama for simulated high school students, then the distant past or space probably isn't simulated to any great degree of accuracy. If our universe was created by a physics PhD student, then distant time or space may well be simulated just as much as here is. Since we can't know if this is a simulation, and we can't know the motivations of our simulators if it is, we can't know whether distant time or space is real or not.

Multiple pasts No, if two universes merged it would practicly create a new universe in which some of the laws of one universe occur and some of the other universe. Well, a merged universe would be two universes, non-identical up to some time t, identical thereafter. What laws would they obey? Well, using my notion of law as compression (see discussions with Tetronian and Eira above), the two universes obey different laws, because they have different compressions. The laws didn't change at time t, although if we cut the universes into temporal slices, and compress those, all purely post-t slices will have the same compression in each universe, all pre-t incorporating slices will have different compressions (and hence different laws).

Generalities You speak of evolution having occured, but it still does. When I say evolution didn't happen, I mean by evolution the hundreds of millions of years of evolution claimed to have happened. I agree that evolution is happening now, and I don't deny present time evolution, just distant past evolution. I think distant past evolution probably would have happened if there existed time for it to happen in, but since I doubt such time existed, thus I doubt it happened. Not going to respond to the rest of this section, since I don't think there's anything you've said I particularly disagree with. (Some of the details you mention may or may not be right, but I don't think that matters to the argument at hand.) --(((Zack Martin)))^™ 22:31, 30 April 2011 (UTC)

We discuss things here; we don't use tq. Go to ASK if you want to do that. sterile^talk 14:09, 1 May 2011 (UTC)

Tq is a very useful template. --(((Zack Martin)))^™ 08:50, 2 May 2011 (UTC)

But it doesn't half make my eyes bleed. ADK^{...I'll derail your glass orb!} 10:01, 2 May 2011 (UTC)

Isn't it nice to have that wall of black broken up with some COLOUR? It makes it easier to read what is a quote and what is not than just plain old "...". --(((Zack Martin)))^™ 10:37, 2 May 2011 (UTC)

It's more the style of fisking I object to. I just don't find it a particularly interesting way of arguing, and tend to agree with the Wikipedia statement, "A fisking is characteristically an incisive and fierce point-by-point rebuttal, and the aim is generally to weaken the target's credibility rather than seek common ground." But, whatever. sterile^talk 19:36, 14 May 2011 (UTC)

I'm not trying to give a "fierce rebuttal". At times a point-by-point one, but to some extent that is driven by the response you are responding to. Some people give highly structured responses, so it is easy to gather up the main points to discuss under one or a few headings. Other people give more wide-ranging responses, in which case your choices are either (1) respond to all or most of their points or (2) pick out a small number of their points to respond to and ignore the rest. Neither approach is ideal. (((Zack Martin)))^™ 10:23, 17 May 2011 (UTC)

Putting the simulation stuff to rest

Let's break down the simulation section into propositions. I will state your assertion in italics (quoted or paraphrased) and then my objections in plaintext.

1. Suppose we are living in a computer simulation. What do you think the probability is that this is true? This is the starting assumption for this entire section of the essay; you should at least say how likely you think it is. I honestly have no idea what I think, but there definitely is a non-zero probability that it isn't true.
2. [Our simulators would] start their simulation with human beings already existing This seems initially plausible, but it's actually wildly improbable because you are making an assumption about what an random alien mind would be like based on what human minds are like. Yet the space of possible minds is so enormously large (see previous link) that we can't make generalizations about what's in that space. It is highly unlikely that the majority of minds would be interested in "playing the Sims"; even the majority of minds who would create our universe probably wouldn't be interested in doing so - there are many, many, many other things in the universe that these minds might be interested in. The simplified version of this argument is "Heck, why wouldn't they want to play Spore instead?" If we take all this into consideration, then statement #2 is pretty improbable.
3. [t]hey'd have no interest therefore in simulating the Big Bang or the theory of evolution. This isn't really important but I want to talk about it anyway: note that this is logically distinct from the previous statement that our simulators would want to play the Sims. In the set of minds who are interested in humans and do want to play Sims with us, there are some who would still simulate evolution. There's a non-zero probability that the alien minds you describe would simulate evolution anyway. So we need to factor this into our probability assessment of #2 (namely, by lowering it slightly).
4. Furthermore, the computational cost of simulating the Big Bang and the theory of evolution is likely vastly higher than just simulating a human-like world; it seems likely that we may have the technology to simulate worlds containing human beings without having the technology or economics to undertake grander simulations including the Big Bang and the theory of evolution. With respect to evolution, the first half of this is simply wrong. To accurately simulate the world as it is now, you need to simulate humans brains; to do so, you need to go atom-by-atom if not deeper. There are much, much, much, cheaper ways of simulating evolutionary processes. If you were to simulate evolution as it happened on Earth, you would need to go exactly as deep as you would to simulate humans minds, so it isn't "more complex" to simulate evolution - it's either exactly as expense or less expensive. (I'm going to ignore the bit about the Big Bang because this is about evolution.) Therefore, this is not an argument that increases the probability of #2 being true.
5. Maybe the universe we are simulated on has radically different laws of physics from our own. Maybe those radically different laws of physics support life that came into being by radically different means. Maybe the theory of evolution doesn't make any sense in their universe. This seems pretty unlikely to me. In order for there to be life without evolution, the laws of physics must make it more likely for beings to just appear than to evolve. This is basically defending the idea that it is more likely that fully functional watches that aren't made of self-replicating parts would appear on the beach than that life would evolve. Sure, there are some universes where this might happen, but certainly not a majority. It would require very, very complex laws that would have to be fine-tuned for this purpose, a condition that is almost certainly not true of a lot of universes. Also, remember that these beings have to be ones that would simulate our universe, which is an insanely specific criterion. As a result, the probability that this would happen is something like 1/(really large number).
6. Maybe there is an infinite hierarchy of simulated universes, and no "actual" universe exists. It is possible that the simulated universe is in turn simulated in another universe, which is in turn simulated in another universe, and so on. This recursion may end somewhere in an actual universe, in which evolution may have occurred. But maybe there is an infinite regress of universe simulations, and there never is an actual universe. Then evolution might never actually occur anywhere. (Note I don't actually believe in this option -- I don't believe in infinity, so I don't believe in infinite regresses of universes either.) I don't believe in this either, but for a different reason. Last time we discusses this I failed pretty hard because I didn't think about the distinction between "we are in an infinite simulation chain" and "an infinite simulation chain could exist." The probability that we really want is the probability of the former. And the answer is the limit of p(s)^n as n approaches infinity, where p(s) is the probability that a randomly selected universe has a parent universe simulating it. This number converges to zero, which makes sense if you think about it: in order to demonstrate that this infinite chain existed, you would need an infinite amount of evidence.
7. Maybe rather than an infinite regress of nested simulations, there is a circular regress of universe simulations. I was strongly opposed to this last time, and I'm strongly opposed to it now. If I turn all the matter the universe into a computer and have it simulate every molecule in the universe, it wouldn't be creating itself by doing so, it would just be simulating an identical copy of our universe. Proof: change something in the code that describes the simulation; this would alter the physical laws of the simulated universe, not of our universe.

Now, let's tie all this together. In order for you be to correct, you need one of the following to be true:

• A: 1 and 2 and 5
• B: 1 and 2 and 6
• C: 1 and 2 and 7

This is very much like saying "If I get a million heads in a row or a million tails in a row, then my argument is correct!" Yes, your argument is based on a disjunction, but the propositions you need to be true are so wildly improbable that it doesn't make much of a difference. Tetronian ^{you're clueless} 16:21, 1 May 2011 (UTC)

All very interesting stuff regarding a simulation argument, but I don't see how it applies to evolution. I mean, from our perspective, what is the difference between "evolution is real" and "evolution isn't real but we live in a simulated universe where it makes it look exactly like evolution is real"? ADK^{...I'll negate your possibility!} 16:36, 1 May 2011 (UTC)

There's no testable difference, of course. I'm just saying that the former is more probable than the latter because the latter requires you to bite a bunch of improbable bullets. Tetronian ^{you're clueless} 16:39, 1 May 2011 (UTC)

I'd go further and imply there is no actual difference. If we were in a simulated reality, the "evolution is true" becomes synonymous with the other choice that it's an illusion. It's like if free will was an illusion, it wouldn't invalidate our experience of it. ADK^{...I'll insult your heretic!} 16:45, 1 May 2011 (UTC)

If you're saying that "in our simulated universe, evolution happened" = "evolution is true," then I agree (heck, that's what I was arguing for). Maratrean is trying to say that in our simulated universe evolution did not occur because our universe was created later and it just looks like it occurred. (Sounds a lot like Last Thursdayism to me, and it's improbable for the reasons I gave.) Tetronian ^{you're clueless} 16:54, 1 May 2011 (UTC)

Yeah, that's what I was saying. It's kind of going beyond there being no testable (falsifiable) difference and saying that those two things are just plain identical. Yes, the Last Thursdayism is a relevant analogy. In fact, it's practically the same assertion. ADK^{...I'll soak your turkey sandwich!} 16:58, 1 May 2011 (UTC)

Agreed - what I was trying to point out with the wall of text above is that it's really, really unlikely that evolution didn't exist/wasn't simulated given what we've observed. In order to make it work out such that evolution is false, you need to pile a whole bunch of assumptions. It makes a lot more sense to believe that evolution happened, simulated or not. Tetronian ^{you're clueless} 17:01, 1 May 2011 (UTC)

It also occurs to me now that A, B, and C all require an additional assumption, which we'll call #8, which is probably the most unlikely of all: our simulators would want to make it look like we evolved. And before you say, "because they don't want us to suspect anything," remember that this is making generalizations about the minds of our simulators, which we can't do. (Hat tip ADK) Tetronian ^{you're clueless} 17:07, 1 May 2011 (UTC)

I started writing a response, and then I thought more about it... and I've decided, let's just drop this argument for now. I still think its got some validity, but its not the best of my arguments. --(((Zack Martin)))^™ 11:39, 2 May 2011 (UTC)

Regarding point 4, building a simulation of our universe would be simplest by starting with the Big Bang - at that point the universe was incredibly simple and only required writing in the Law of Everything. Then you just let it run and see what happens. Everything else that happens is just one set of possible consequences of the initial state. ħuman 16:05, 17 May 2011 (UTC)

"Argument from multiple pasts"

I honestly don't even how to begin addressing the arguments in this section. Most of them are wildly improbable and the rest are pretty confused. The whole section seems to be based on this assumption: "Likewise, if a universe can split in two in the many-worlds interpretation, might two universes not merge together?" To which I would reply: No. This has absolutely nothing to do with what MWI actually says - it's not a logical implication or even an interpretation of the theory. As a result, it's not something that you can just tack a high probability onto - instead, its pretty unlikely. Heck, I don't know whether this idea that "universes can merge" is even coherent - it sounds more like something that results from being confused about what a "universe" is than something that could actually happen. Next, you seem to be implicitly assuming your conclusions from the previous section, which, as I pointed out above, is actually a very bad idea. And even if you are correct about the simulation stuff and you're correct about the fact that universes can merge, how do you know that ours did do so? There's an additional assumption - and thus an additional probability that you have to multiply by. Finally, even if we assume that this confused state of affairs could actually happen and a creationist universe and an evolutionist universe did merge to form our own (which itself is yet another huge assumption and thus another huge burdensome detail), that wouldn't mean that evolution is "both true and false" - it would simply mean that a creationist universe and an evolutionist universe merged to form our universe. Period. Overall, this argument is a conjunction of statements that are either unlikely or not even wrong. Tetronian ^{you're clueless} 16:35, 1 May 2011 (UTC)

"Universes can merge" is about as coherent as "universes can split". Imagine a universe, simplified down as far as it needs to be to show the example, that is in state A. A quantum decision happens and it splits to state B and B'. Is there a quantum decision whereby B and B' can move to the same state C? And if we have two universes now in state C have they, in principle, merged? ADK^{...I'll vocalise your reindeer!} 16:41, 1 May 2011 (UTC)

You're probably right about that, and MWI does allow for universes to "merge" and "interact" (in quotes because I don't fully understand it) with each other before they completely "decohere," but it seems like this doesn't apply to what Maratrean is talking about, since he's talking about two completely separate universes developing to the point where they are atom-by-atom identical and then coming together. Tetronian ^{you're clueless} 16:50, 1 May 2011 (UTC)

The trouble with that one is that in order to get two universes to be atom-for-atom identical, from different starting points, is that they'd have to be extremely similar just before they became identical and "merged". So if evolution was going on in one, it wouldn't be a massive assumption to say that evolution was going on in the other. ADK^{...I'll bamboozle your ripple!} 16:55, 1 May 2011 (UTC)

Exactly. That what I was getting at with "even if we assume that this confused state of affairs could actually happen and a creationist universe and an evolutionist universe did merge to form our own (which itself is yet another huge assumption and thus another huge burdensome detail)" (admittedly it was worded poorly). What I mean is, Maratrean's scenario is not supported by MWI because of the argument you just gave. Tetronian ^{you're clueless} 16:59, 1 May 2011 (UTC)

OK, first of all... there are many possible theories of parallel universes. MWI is just one of many. Here are some others: (1) Lewisian modal realism (every "possible world", as philosophers mean it, is actual), (2) Tegmarkian radical platonism (a universe is just a sufficiently complex mathematical object; since other equally complex mathematical objects exist, other universes must exist too), (3) various non-MWI multiverse theories in physics (e.g. brane cosmology, chaotic inflation, etc.), (4) computer simulation theories (sibling simulations, parent simulations, etc., are other universes to ours), (5) theistic models (hey, if God can choose to make one universe, why can't he make more than one?). So there are at least 6 different (groups of) theories of parallel universes. I'm not referring to any of them in particular, just the concept in general. Personally, I would tend to reject the MWI, Lewisian and Tegmarkian approaches; in terms of what I believe may be actually true, my own preference is for the non-MWI physics multiverses, simulationist and theistic models. But really, my point is to defend the general concept, rather than any particular instance of that concept. And if you accept any of these 6 approaches, then you've accepted the general concept, even though they are all very different (and aren't necessarily all compatible with each other).

What do I mean by two universes merge? Well, can we come up with a common definition of universe which works, regardless of which (if any) of the 6 types of parallel universe theories one adopts? A universe can be viewed as a set of points in a spacetime continuum, and those points have some finite set of properties. By transforming those properties into additional points, we can reduce a universe to a set of points in a multidimensional space. Taking one of those dimensions as time (and putting relativistic objections aside for now), consider two such spaces, which are identical prior to some time t, and different afterwards - can't we say one universe divided into two? Or we might say two distinct-yet-heretofore-identical universes began to differ. Whether we call this division or not is maybe an empty question, maybe we should follow Tetronian/Yudkowsky's advice and taboo it. Similarly, we can define merger as a temporally symmetric process - different prior to t, identical post-t.

So, could we be in the merger of a creationist and evolutionist universe? Well, I can't see any reason, following any of those 6 groups of theories, why we couldn't be. Maybe some of those (groups of) theories would make this a more or less likely possibility than others. But, here comes the real problem:

1. We don't know which if any of those theories is true
2. We don't even know how to assign probabilities to them, or a probability to the claim that one of them is true
3. Assuming any one of those (groups of) theories is true, it's not very clear how one could even begin to calculate the resultant probability of the creationist-evolutionist merger scenario

So, what is P(this universe is the merger of a creationist and evolutionist universe)? We don't know what it is, we don't even know how to begin to assign it a probability. Maybe then we should just say, if all else fails, let's use a uniform prior. So, P(this universe is the merger of a creationist and evolutionist universe) = 0.5. In which case, we really can't know anything about the truth or falsehood of evolutionism or creationism. There's a fifty-fifty chance they are both true simultaneously.

Alternatively, maybe we should say there are four choices: neither is true, creationism is true, evolutionism is true, both are true. This gives us 0.25 for each choice, and again P(evolutionism)=0.5 and P(creationism)=0.5. --(((Zack Martin)))^™ 11:04, 2 May 2011 (UTC)