Tuesday, 27 September 2016

Another Chance of Design - Response to Travis R

There's been a short exchange in the comments following Chance or Design:

measureoffaith - FYI, the objections you list here appear to have been sourced from WLC rather than Robin Collins, and the accompanying reference to Penrose is on pages 762-765 of TRtR (The Road to Reality).

neopolitan - Thanks, I've updated accordingly. I don't think that pages 762-765 say what you want them to say. Penrose is arguing against the anthropic principle. Towards the end of an earlier section, "28.6 The anthropic principle", he writes (having linked the strong anthropic principle with a creationist god hypothesis):

"My own position is to be extremely cautious about the use of the anthropic principle, most particularly the strong one. My impression is that the strong anthropic principle is often used as a kind of ‘cop-out’, when genuine theoretical considerations have seemed to reach their limit. I have not infrequently heard theorists resort to saying something like: ‘the values of the unknown constant parameters in my theory will be ultimately determined by the anthropic principle’. Of course it might indeed ultimately turn out that there is simply no mathematical way of fixing certain parameters in the ‘true theory’, and that the choice of these parameters is indeed such that the universe in which we find ourselves must be so as to allow sentient life. But I have to confess that I do not much like that idea!"

Note that he moves from having particular issue with the strong anthropic principle to just referring to it as the anthropic principle. Thus, when he's protesting strongly against the anthropic principle in a later section, he is most particularly protesting against the strong anthropic principle, and thus against your god. Given the context, it's a little disengenuous to call upon Penrose in support of your case.

I see no strong objection in Penrose's book against multiverses. Even when we limit ourselves to the very specific thing that WLC could be thought of as honestly referring to - the extravagance associated with having such a large, long-lived universe when perhaps we need a much small(er) region of order, no more than one galaxy, with the current laws in place only for as long as required for humans to evolve - we see that Penrose is arguing that for the purpose indicated (creating us, apparently) there would have been 10^10^123 more options that were significantly less extravagant. This is a strong argument against god, not a strong argument against multiverses. If anything, it implies that if there are multiverses (and thus more likelihood of the initial conditions from which intelligent life might spring) then the argument against god only increases.

measureoffaith (writing as Travis R): You assume too much. I don't "want" Penrose's argument to say anything in particular, nor am I making a case for any particular view. I was simply skeptical of the story put forth in your original version and so wanted to inform you of the correct sources after locating them for myself. Perhaps I should have been more explicit - it is WLC, not me, who refers to pages 762-765 of Penrose'sTRtR in the context of the quote. So the point was that your remarks about WLC presumably (and amusingly) referring to pg 784 is a strawman and is probably best exorcised from the post. As far as I can tell, WLC accurately characterizes the cited argument from Penrose, though he simultaneously fails to acknowledge the accompanying implications for theism that you outlined.

You are right, Travis, I assumed too much and misspoke (or miswrote).  I perhaps should have written " I don't think that pages 762-765 say what WLC wants them to say" or " I don't think that pages 762-765 say what John Piippo wants them to say" or " I don't think that pages 762-765 say what the theist might want them to say".  Probably, however, I should have just stuck with the facts and avoided speculation as to what other people want.

My point was that John Piippo was presenting arguments against the multiverse and had quoted WLC who made reference to Penrose.  And in the Penrose book, the word multiverse is only used once, on page 784, after which he uses the term "omnium".

It is true that WLC, as you linked, was referring to a different section of Penrose's book.  The questions then are whether WLC was "accurately characterising" Penrose's argument - and whether John Piippo was accurately reporting WLC's case.  WLC seems to have used Penrose repeatedly, in his book On Guard, on the page you linked and also at his Defenders podcast.  Here's what WLC had to say in the last of these:

Moreover, thirdly, the Many Worlds Hypothesis faces what may be a truly devastating objection. Do you remember when we talked about the thermodynamic properties of the universe, we discussed Boltzmann’s Many Worlds Hypothesis? You will remember that the Austrian physicist Ludwig Boltzmann tried to explain away the current disequilibrium of the universe by a kind of Many Worlds Hypothesis. He said that the universe as a whole really is in a state of equilibrium but there are just little pockets of disequilibrium throughout the universe, and these are different worlds. He called them “worlds” and we are one of these little pockets. We are one of these worlds. You will recall what sank Boltzmann’s hypothesis was that if our world is just a random member of a World Ensemble like this, then it’s vastly more probable that we should be observing a much smaller region of order than the vast universe that we do. In order for us to exist, all you would need would be a small fluctuation from equilibrium, say, enough to produce our solar system and not an entire universe which exists in such a state. It turns out that a parallel problem faces the Many Worlds Hypothesis as an explanation of cosmic fine-tuning.

The Oxford University physicist Roger Penrose has pressed this objection with great force. Penrose points out that the odds of our universe’s initial low entropy condition existing by chance alone are somewhere on the order of one chance out of 1010(123). A truly incomprehensible number. By contrast the odds of our solar system’s forming by just a random collision of particles, Penrose calculates to be about one chance out of 1010(60). A number which is so tiny in comparison to 1010(123) that Penrose calls this number “utter chicken feed” in comparison with 1010(123). What that implies is that it is far more likely, incomprehensibly more likely, that we should be observing an orderly universe no larger than our solar system, since a world like that would be unfathomably more probable than a finely tuned universe like ours.

To me, this is not an "accurate characterisation" of what Penrose had to say.  Craig was very clearly implying that Penrose was pressing an objection to the "Many Worlds Hypothesis as an explanation of cosmic fine-tuning".  It's very difficult to interpret what was written here differently. 

Now, Penrose did write:

Much more problematic are versions of the strong anthropic principle, according to which we try to extend the anthropic argument to determine actual constants of nature (such as the ratio of the mass of the electron to that of the proton, or the value of the fine structure constant §26.9, §31.1). Some people might regard the strong anthropic principle as leading us to a belief in a ‘Divine Purpose’, whereby the Creator of the universe made sure that the fundamental physical constants were pre-ordained so as to have specific values that enable sentient life to be possible. On the other hand we may think of the strong principle as being an extension of the weak one where we broaden our questions of ‘where’ and ‘when’, so that they apply not just to a single spacetime, but to the whole ensemble of possible spacetimes (Fig. 28.13b).27 Different members of the ensemble might be expected to possess different values for the basic physical constants. The where/when question now also involves a choice of universe within the ensemble, so again we must find ourselves in a universe which permits sentience to come about.

Penrose is not necessarily talking about a multiverse here, but of an ensemble of "alternative universes", which involves a range of possible universes - not necessarily a range of instantiated universes.  The difference here is subtle.

Put roughly, we arrive at the idea of a multiverse via three possible paths, none of which involve thinking about a god: there is something like string theory in which each universe is a different solution to the equations, none of which has a higher likelihood than any other; there is the patchwork greater universe, in which for one reason or another, the laws of physics and the fundamental constants vary from region to region (eternal inflationary theory fits in here); and, some sort of cyclical or branching multiverse, like Penrose's CCC or a mother-daughter relationship between universes mediated by black holes, in which the constants are randomised in each cycle or branch.

The ensemble of worlds idea is a little different, especially as it pertains to the strong anthropic principle.  The basic idea is that not only is it a truism that we live in a universe in which life of our sort is possible, but also that sort of universe must also be possible - our sort of universe is a necessary member of any set of possible universes, by virtue of the fact that at least one example of our sort of universe exists.  If you come up with a theory that expressly prohibits a universe of the sort we live in, then your theory is wrong.

Just in case it is not entirely clear, the difference between the multiverse and the world ensemble is the direction from which the idea is approached.  As I wrote in Chance or Design, consideration of fine-tuning resolves down to chance or design.  If you find design to be unpalatable, then you are left with the question of how it could be that a universe so (apparently) unlikely as ours should exist.  A potential solution hangs on the notion that our universe, however unlikely, is still possible (and necessarily so, since it is existent).  This is the point at which you might posit a world ensemble, an array of possible universes, all slightly different and numerous enough to drive the posterior likelihood of our sort of universe towards unity … Pr(our sort of universe|world ensemble) -> 1.

What you can't do, legitimately, is suggest that there is a world ensemble purely on the basis of finding design unpalatable.  What you can do, legitimately, is look around and see whether there is any good reason for thinking a world ensemble exists.  It is at this point that you might meet up with multiverse theories coming in from another direction.  Some theists might not believe that multiverse theories arose independently of apologetics, but there are some who are becoming aware that this is in fact the case.

Another approach is Bayesian in nature (the equation above should have given this away).  We are considering a posterior, P(U|WE) which is given by the prior P(U) multiplied by the likelihood P(WE|U) divided by the marginal likelihood P(WE).  If we were to erase all knowledge of there being any universe in existence, what is the (marginal) likelihood of a world ensemble?  I'd suggest that this would approach zero, since the absence of any universe doesn't move us anywhere close to thinking there should be many of them (that are possible).  Therefore, we have a very low number, according to fine-tuners, for P(U) divided by a very low number.  This is rather arbitrary, but we could say that it's close to zero - especially if we were to stipulate that this world ensemble should be very highly populated given that the more highly populated it is, the lower P(WE) would be.

So, P(U)/P(WE) ≈ 1 and therefore P(U|WE) ≈ P(WE|U).  We need to consider how likely a world ensemble is, given the existence of our universe.  We could consider this in terms of how likely it would be that there is no world ensemble, given the existence of our universe - in other words, how likely would it be that, if there were only one universe, this would be the universe that came into existence?  If you say "very unlikely", then you are saying that a world ensemble, given the existence of our universe, is "very likely".  Once we've accepted that a world ensemble is highly likely, we need only to work out how populous this world ensemble would be.  With nothing else to guide us, we find ourselves being driven towards an infinite number of universes - because there is one population size for the world ensemble to the left of three and an infinite number of sizes to the right, so it's more likely to be a population size to the right of three.  Keep going (forever) and you'd eventually arrive at the conclusion that infinity is the most likely size.

I'm aware that this argument is a little dodgy, but fortunately, we don't need to rely on Bayesian skulduggery nowadays because we have pretty clear indications that the multiverse is an actual thing.

Anyway, it is very clear that, in pages 762-765, Penrose was forcefully dealing with a theistic version of the strong anthropic principle because he kept mentioning a Creator.  WLC cannot be thought of as "accurately characterising" Penrose's position when he fails to mention that.

Monday, 26 September 2016

Falling Trees, Rainbows and a Gift for Theists

In 1710, Bishop George Berkeley pondered a question that was first formulated (in print) in The Chautauquan (a magazine) in 1883:

This is not to say that Bishop Berkeley was some sort of time-traveller but merely that, like many of the theologically inclined, he was attempting to answer a question that had not yet been properly posed.  Berkeley wasn’t really trying to answer the question, but rather to put forward an argument for immaterialism (or subjective idealism) which he makes most strongly in his “Master Argument”:

I am content to put the whole upon this issue; if you can but conceive it possible for one extended moveable substance, or in general, for any one idea or any thing like an idea, to exist otherwise than in a mind perceiving it, I shall readily give up the cause…. But say you, surely there is nothing easier than to imagine trees, for instance, in a park, or books existing in a closet, and no body by to perceive them. I answer, you may so, there is no difficulty in it: but what is all this, I beseech you, more than framing in your mind certain ideas which you call books and trees, and at the same time omitting to frame the idea of any one that may perceive them? But do not you your self perceive or think of them all the while? This therefore is nothing to the purpose: it only shows you have the power of imagining or forming ideas in your mind; but it doth not shew that you can conceive it possible, the objects of your thought may exist without the mind: to make out this, it is necessary that you conceive them existing unconceived or unthought of, which is a manifest repugnancy. When we do our utmost to conceive the existence of external bodies, we are all the while only contemplating our own ideas. But the mind taking no notice of itself, is deluded to think it can and doth conceive bodies existing unthought of or without the mind; though at the same time they are apprehended by or exist in it self.

Berkeley summed up his theory with "esse est percipi" ("To be is to be perceived") so his answer to the question as it is generally posed today would apparently be a resounding “no”.

There are others who would agree with a no verdict, given a slight modification (and an update) to the more common question:

If a tree fell in a forest and there was no-one and nothing there to hear, would it make a sound?

Such a formulation allows those who associate sound with the perception of pressure waves to answer with “no” – because someone or something would have to be around to register the pressure waves as sound for there to be a sound.  Physicists might disagree because those pressure waves are sound, by definition.  But here the difference is little more than semantics.  Those arguing that perception is sound are not arguing against the existence of pressure waves after the toppling of a tree in a deserted forest and physicists are not arguing that the presence of sound (as pressure waves) will necessarily bring a perceiver into existence.

There is a related phenomenon with rainbows, specifically in the fact that you and I never see the same rainbow.

The rainbow that we see in the sky isn’t actually there, it only exists in our heads after light has entered our eyes and been assembled by the brain into the colourful arch shape we recognise.  What has happened is that light has been refracted (and polarised) in thousands if not millions of drops of water, being split into the spectrum in the process before making its way to us.  Once the light has passed through the lenses of our eyes (or the lens of a camera when taking a photo of a rainbow) an image consistent with the rainbow is formed and it is this that is sent to the brain.

We can get all semantic about where the image is, either in the eye or in the brain, but the point is that outside of our heads there is nothing that corresponds with the rainbow that we perceive.  (Some might want to make an exception for a rainbow photo, but this is just outsourcing the image generation process – it has been done by a camera instead of our eyes.)

So how is this similar to a tree falling in a forest?  I’m going to make a rash assumption here that you, the reader, have two functioning ears – but I am not going to assume that your aural acuity is the same as mine.  Imagine then that we stand side by side in a forest and see, in the distance, a tree falling.  A short time later we hear the resultant sounds.

Because we are in a forest with plenty of other trees and maybe even bushes along with various topographical features, the sounds that we hear of the tree falling will be a combination of direct sound (since we saw the tree falling, there’s a clear line of sight) and sound reflected off tree trunks, branches, leaves, rocks, water and so on – along with reflections off each other and ourselves.

Slightly different combinations of reflected sound enter each of our ears (that is my two ears and your two ears) and our brains assemble a single soundscape of the tree falling from the range of frequencies that we detect – but those soundscapes (mine and yours) are not the same.

Additionally, our individual soundscapes – as perceived by us – would not have existed had we not been there interacting in the environment and picking up the sound from our ears in precisely the locations that they were in.  This is nothing magical because, conceptually, we could have put a pair of androids in the forest with recording arrangements that exactly matched our aural equipment and bodies that exactly mirrored our impact on the environment – then they would “hear” the sounds that we would have heard, if we had been there.

However, without someone or something to register those particular soundscapes, the soundscapes simply wouldn’t exist – in the same way as a rainbow doesn’t exist unless someone or something is there to focus light onto a receptor.  The pressure waves from the fallen tree will still be there just as the polarised light emerging from rain drops will be there, irrespective of whether there is a witness or not.

How could this been seen as a gift to Christians?

Unlike Islam and Judaism, Christianity involves a story in which a god is incarnated in human form (but only once, unlike Hinduism in which each deity seems to have a number of avatars – a Hindu may need to correct on this).  To be able to experience a rainbow or the soundscape of a tree falling in a forest, a god would have to be incarnated – because each of these phenomena is a consequence of having a single location and limited perception.

It’s relatively simple for someone like me to come up with the falling tree and the rainbow as examples of experiences that cannot be shared with an omnipresent omniscient god and it is quite likely that there are a range of similar phenomena, some of which might have been important or intriguing enough for a god to take on an incarnation in order to experience them.

The exact details, of course, would have to be sorted out by an apologist or theologian.


(Theists should be wary of non-theists bearing gifts, by the way.  These gifts could easily be bait for a trap.  It is up to the theist to identify just what the nature of trap is.)

Thursday, 22 September 2016

Chance or Design?

In Barnes' Objections to Fine-Tuning, I concluded that there are only two fundamental responses to claims fine-tuning, that fine-tuning (and/or the appearance of fine-tuning) is due to chance or that fine-tuning (and/or the appearance of fine-tuning) is due to design, since the other options inevitably collapse down to chance or design.

We should perhaps revisit Barnes' "11 objections" in light of this:

Chance: It’s just a coincidence

Chance (overlaid by an appeal to ignorance): We’ve only observed one universe, and it’s got life. So as far as we know, the probability that a universe will support life is one out of one!

Chance/Design: However the universe was configured, evolution would have eventually found a way

Chance/Design (with another appeal to ignorance): There could be other forms of life

Chance/Design: It’s impossible for life to observe a universe not fine-tuned for life

Chance/Design: Maybe there are deeper laws; the universe must be this way, even though it looks like it could be other ways

Chance: Maybe there are bajillions of universes, and we happen to be in one of the few that supports life

Design: Maybe a physics student in another universe created our universe in an attempt to design a universe that would evolve intelligent life

Chance: This universe with intelligent life is just as unlikely as any other universe, so what’s the big deal?

Chance: The universe doesn’t look like it was designed for life, but rather for empty space or maybe black holes

Design: Fine-tuning shows there must be an intelligent designer beyond physical reality that tuned the universe so it would produce intelligent life

I have left a few of them as undetermined, Chance/Design because, at the end of the day, these "objections" don't really distinguish between the two fundamental options.  For example, while "(no matter how) the universe was configured, evolution would have eventually found a way" implies an end goal (intelligent life) that evolution is "trying" to achieve, there's nothing inherent to the argument that prefers (cosmic) evolution being designed to find intelligent life over (cosmic) evolution simply stumbling upon it.  The latter sort of relies on our knowledge that intelligent life is - at the very least - possible in one possible sort of universe, even if it may be improbable and the implication is that, given enough time and/or space, (cosmic) evolution would therefore eventually lead to intelligent life.

The main problem, the problem that theists want us all to come unstuck over, is that the fine-tuning of our universe for intelligent life does appear to be highly improbable.  We are supposed to throw up our hands and say "It's so unlikely that this should have happened by chance, so it must have happened by design.  Therefore, god."

It's for this reason that the multiverse is disliked by some theists, the multiverse short-circuits the theistic fine-tuning argument, because if there are an infinite (or sufficiently large) number of universes, with random tunings, then it becomes a lot more likely that some of them will be tuned sufficiently well for intelligent life.  If there are universes without end, a potential infinity of them, and it is possible that a universe may be tuned for intelligent life (which we know to be so), then it becomes statistically certain that there will be universes in which intelligent life arises - so such a universe existing becomes unsurprising and its existence cannot be counted as evidence for design.

Note that a universe with intelligent life is not evidence against design in and of itself but, given a claim with respect to a particular type of designer, a particular type of universe can be evidence against that designer (hence the problem of evil and the existence of vagueists, theists who strip away anything and everything associated with their god that might permit it to be falsified).

Barnes' list does have a multiverse related "objection" to fine-tuning: "Maybe there are bajillions of universes, and we happen to be in one of the few that supports life".  This is a somewhat flippant way to describe the multiverse, but they seem to be Luke Muehlhauser's words, not Luke Barnes'.  In the Pale Blue Dot podcast that Barnes appeared on, he confirms that we don't necessarily need an infinite number of universes, merely "enough" to make the supporting of life, somewhere - in one of those universes, likely.

This is part wriggle and part lure.  It seems reasonable to answer the argument that this universe is highly unlikely with one that, while not certain, nevertheless is likely.  However, the theists have a philosophical argument to the effect that their god is not only likely, but necessary.  In their minds, it doesn't matter if our universe is likely on a naturalistic assumption, given the multiverse - because they have the universe being the necessary product of a necessary being.  (It doesn't seem to matter to them that their necessity arguments have holes in them large enough to fit a few multiverses - they still have an argument.)  The lure involves encouraging those thinking about multiverses to satisfy themselves with a less than infinite number of universes (even a less than ridiculously huge, but not infinite, number of universes).  It's more of a rhetorical trick than anything else since the equations will tell us how many universes fall out of a multiverse theory, not any desire to explain fine-tuning.

Rather strangely, when discussing the multiverse with Muehlhauser, Barnes doesn't start with any of the scientific theoretical models that lead to a multiverse, like Guth's eternally inflationary multiverse, or string theory.  No, he starts with a couple of philosophical multiverse - although he does express bafflement at them.  Perhaps, we could think he's just dispensing with the nonsense first.  But no.

Directly after mentioning (and mischaracterising) eternal inflation, he leaps into typicality and Boltzmann brains.  Now I know that some well-educated, apparently sane and respected people do apparently take Boltzmann brains seriously, but I don't.  Briefly, the idea is that random fluctuations in thermal equilibriums, given enough time and space, will sometimes create a "brain", which I interpret to be little more than a nexus of something or other that is (or becomes) conscious, but is not necessarily encased in walnut like globs of flesh.  These could fluctuate into existence with a complete history in place and, albeit briefly, it would be impossible to distinguish between the existential experience of these Boltzmann brains, and that of our brains.

Furthermore, the argument goes, these fluctuations would be far more common (due to entropy considerations) than instances in which brains like ours evolve out of some primordial soup over a period of three to four billion years.  So, if this were true, the fact (if it indeed is a fact) that we humans have the nature that we have rather than being Boltzmann brains would be very unlikely.  We'd be very untypical of intelligent beings in general, since most of them would be fluctuations that dissipate soon after coming into existence.

I think this is a nonsense argument for the basically the same reason that, although it is theoretically possible in quantum physics for someone to spontaneously teleport from one spot to another, spontaneous quantum teleportation of humans will never happen.  The fluctuation required for an intelligence (even one as humble as my own) to come into existence and have pre-loaded experience is extremely specific - it's very highly ordered, which means that it's very low entropy (it's also very "surprising" but more of that in a later post).  I would consider the fluctuation of this intelligence into existence, pre-packaged with experience and awareness, without the slow grind of evolution behind it to be sufficiently astonishing as to be miraculous.

What I observe, as inherent to the Boltzmann brain argument, is an effect that I'd like to term "inconsistent poverty of imagination".  The theist is willing, when confronted with the idea of a multiverse, to imagine all sorts of nonsense and then place what we know to exist (intelligence based on evolution from very humble beginnings) on a par with the nonsense that they just thought up (intelligence based on thermodynamic fluctuations in some high entropy region of a universe or multiverse), but when asked to imagine alternatives to their god, all that imagination suddenly dries up and they can't think of a thing.

There are also rhetorical games played with infinities.  If there are an infinite number of universes, then anything that can happen will happen, and if something can (and does) happen, it will happen an infinite number of times.  This means that if Boltzmann brains are possible and they can fluctuate into existence, then they will do so an infinite number of times (but not necessarily everywhere, all the time).  Similarly, if intelligence as a consequence of cosmic and biological evolution is possible, then it will happen and it will happen an infinite number of times.  The argument is that Boltzmann brains would occur in high entropy universes (which may be thought of as being common and plentiful, and thus unsurprising) while the evolutions (cosmic and biological) that led to us could only happen in low entropy universes (which may be thought of as being rare and unlikely, and thus surprising).  We then arrive back at a sort of geocentricity-like situation, while our planet is not the centre of the universe, our universe is of a very special type rather than being typical.  From this it is argued that Boltzmann brains (as temporary denizens of the far more common high entropy universes) are more typical than we are, so we should be surprised at not being a Boltzmann brain in a different type of universe.

I disagree.

We have at least one more thing to consider, our persistence.  If we considered only one aspect of ourselves in isolation, that we are conscious and aware, then sure we might be surprised that we are not a Boltzmann brain.  But we are also persistent, we don't dissipate.  And Boltzmann brains will dissipate because, by nature, they are fluctuations in high entropy, thermally flat universes.  They represent a region of low entropy and very argument that leads to them assumes the second law of thermodynamics, that entropy increases.  The Boltzmann brain would necessarily decay, about as quickly as it came into existence, and return to equilibrium.  Absent magic, the Boltzmann brain could not choose to persist, or to replicate itself.

In other words, we are not just a thing (intelligence), we are thing of a particular type (persistent intelligence, noting that a host of other adjectives could be involved).  If I were to say that I am human, and consider only that, then I should be surprised if I was neither Asian nor African (who together make up more than three quarters of the world's population).  But if I were to note that I also have a genetic abnormality (say mutation to the melanocortin-1 receptor on chromosome 16), then I should not be at all surprised if I had pasty white skin, bright red hair, a vile temper and lived in Auchtermuchty (in Fife, Scotland not that far from Ladybank, which sounds like a euphemism - also not that far from St Andrews, ancestral home of "sweary rambling with sticks" (also known as golf)).

Being a persistent intelligence, it should come as no surprise that I am not a Boltzmann brain and for that reason, I think this rather stupid objection to multiverses fails.  (It also fails because, if Boltzmann brains are a problem, they are also a problem for monoverses.)

So, are there any meaningful objections to the multiverse other than Boltzmann brains?  Well, there are three objections from Robin Collins WLC, as summarised here by John Piippo:

For in order to be scientifically credible, some plausible mechanism must be suggested for generating the many worlds. But if the many worlds hypothesis is to be successful in attributing fine-tuning to chance alone, then the mechanism that generates the many worlds had better not be fine-tuned itself. For if it is, then the problem arises all over again: How do you explain the fine-tuning of the multiverse?

(The BGV theorem) requires that even a multiverse of bubble universes must have a beginning. In that case the mechanism that generates the bubble universes has been chugging away for only a finite amount of time. So by now, there may well be only a finite number of bubbles in the world ensemble, which may not be enough to guarantee the appearance of a finely tuned universe by chance alone. There's no evidence that the sort of world ensemble required by the many worlds hypothesis actually exists.

If our world is just a random member of a world ensemble, then it's vastly more probable that we should be observing a much smaller region of order. It turns out that a parallel problem faces the many worlds hypothesis as an explanation of fine-tuning. [Oxford physicist] Roger Penrose has pressed this objection forcefully.

The first objection, re fine-tuning of the multiverse, is merely a caution that a theoretical multiverse, presented as an objection to god as designer, cannot be fine-tuned.  Okay, thanks for that.  It's not really an objection to the multiverse per se and there's no indication that I am aware of that any of the theoretical multiverse necessitate fine-tuning.

The key element in the second objection is that there is no evidence for a multiverse, but thing is that there is evidence, certainly evidence for a multiverse generating process (watch George Efstathiou's comments, indicating that Planck data constitutes evidence in support of eternal inflation).  Even if there were no scientific evidence at all in support of a multiverse, this would not mean that the multiverse would be less supported than the god did it theory.  And with the multiverse theory, there are things that theoreticians can look out for because the theory is testable.

The third argument is actually associated with the Boltzmann brain argument (order and entropy are inextricably linked concepts).  Again, the argument is based on selected aspects of our existence and when we consider the totality of our existence, then we should not be surprised that we live in the sort of universe that we live in since it's clearly a possible universe and it's just the sort of universe that permits intelligence like ours to develop.  This objection seems to miss the point rather spectacularly.

A quite amusing aspect to Collins'  WLC's third objection is the reference to Roger Penrose (note that I changed the link to something more relevant than the Amazon page for The Road to Reality: A Complete Guide to the Laws of the Universe).  In the book that Piippo links to, Penrose mentions the word multiverse on only one page.  According to the index this was on page 783, but I could not find it on that page.  This review indicates that it might be on page 784 (which is not part of the Google Books review).  And the mention of multiverse is only to say that Penrose prefers the word "omnium" to "multiverse", a strange position to take if you are arguing forcefully against the fundamental concept (confirmed).  Additionally, Penrose's conformal cyclical cosmology is a temporal form of a multiverse, with our universe being reset and recycled ad infinitum (and Penrose claimed that circular patterns in the CMB data from WMAP were suggestive of earlier universe, some might claim that they are suggestive of young bubble universes bumping into each other or side-effects of inflation, while others might suggest that some people are just seeing what they want to see).

<edit> The blogger measureoffaith (see comments below) suggests that Penrose forcefully makes the case that multiverses face the same problem with fine-tuning that our universe does in sub-chapter 28.7 The Big Bang’s special nature: an anthropic key?  It would appear, however, that this section must be read very optimistically by a theist, especially when Penrose's conclusion mirrors mine - that it comes down to either design or chance, that god did it or there's some mathematical/scientific reason why the universe is the way it is, and that it's worthwhile investigating the latter.

Robin Collins also presents some objections to the multiverse, in this document.  His objections relate to the nature of a "many-universes generator".  I wrote about these objections in "The Four Mechanisms of the Ignopalypse", but I am holding off on publishing it (or was at time of writing, if you are reading this later).  It should be up later in the year.  For the moment, suffice it to say that I don't find Collins' objections to be meaningful or substantive. <end edit>

If there are any meaningful and substantive objections to multiverse theory, I would be keen to hear of them but so far there seems to be little more than a chorus of appeals to incredulity.

In conclusion, the fine-tuning of the universe can really only be explained by chance or design, since all other objections resolve down to one or the other.  I'm not overly fussed by the nature of the designer, since I don't consider a designer to be the correct answer anyway (for other reasons, quite separate from the theoretical impossibility of design).  That said, given the nature of the design argument, nothing we ever come across will be sufficient to eliminate design as a theoretical possibility - since a designer could have created the universe with the intention to make it totally indistinguishable from a universe that came into existence by chance.  All that we have is a counter to the argument that a designer must exist because there is no other alternative.  We do have an alternative, in the form of a multiverse.

Something that is worth considering, particularly if you are a pro-fine-tuning, anti-multiverse theist, is that science is inching closer and closer to proving that the multiverse is reality, rather than just hypothesis.  If you have nailed your colours to the notion that fine-tuning is a knock-down argument for god because you think that the multiverse might not exist, it is high time that you reconsider your position. (Much as Jeff Zweerink has - listen to the second impressive moment.)

Wednesday, 21 September 2016

Barnes' Objections to Fine-Tuning

It occurs to me that now Barnes has his book out, he may well be invited to speaking opportunities or debates and when he is, he may fall back (WLC style) on his standard arguments.  In a debate, you can't go into huge detail with respect to each of your points, although you can do what is known as a Gish Gallop (proof by verbosity) and spurt out so many factoids and positional statements that your opponent cannot hope to rebut all of them in an intellectually satisfying way.

My suspicion is that Barnes will, if given the opportunity, rely on this technique.  I base this suspicion on his interview with Luke Muehlhauser at the Pale Blue Dot podcast, in which he listed "11 objections" to fine-tuning.

Right, first off, there weren't 11 "objections", at best there were 10.  The final "objection" wasn't an objection at all, it was the staff answer for the vast majority of people pushing the fine-tuning agenda: "god did it".  And there weren't really 10 anyway, since a few of them fall into distinct categories.  And not all of them were objections to fine-tuning per se, for the most part they were objections to the staff answer.  One wasn't even an objection.

Let's look at the broad categories:

Denial: there is no fine-tuning, so there's no problem.

Chance: there is fine-tuning, but it comes down to chance that this universe had fine-tuning.

Necessity: there is fine-tuning, but that is just part of the way the universe is.

Design: there is fine-tuning and that was intentional.

Barnes basically Gish galloped through the first of his 10 objections which were (in Muehlhauser's words):

Chance: It’s just a coincidence
Chance (overlaid by an appeal to ignorance): We’ve only observed one universe, and it’s got life. So as far as we know, the probability that a universe will support life is one out of one!

Denial: However the universe was configured, evolution would have eventually found a way

Denial: There could be other forms of life

Necessity: It’s impossible for life to observe a universe not fine-tuned for life

Necessity and Chance/Design: Maybe there are deeper laws; the universe must be this way, even though it looks like it could be other ways

Chance: Maybe there are bajillions of universes, and we happen to be in one of the few that supports life

Design: Maybe a physics student in another universe created our universe in an attempt to design a universe that would evolve intelligent life

Chance: This universe with intelligent life is just as unlikely as any other universe, so what’s the big deal?

Denial: The universe doesn’t look like it was designed for life, but rather for empty space or maybe black holes

Design: Fine-tuning shows there must be an intelligent designer beyond physical reality that tuned the universe so it would produce intelligent life

Let's look at the necessity first.  It is simply a truism to say that, in order for intelligent observers to observer a universe (from inside the universe), that universe must be conducive to intelligent observers.  If the intelligent observers in question are alive and require certain stringent conditions to be met in order to remain alive then, during the period in which they observe the universe, the universe will meet these stringent conditions.  This will be the case irrespective of whether the universe is designed or not.

The necessity argument is not an argument against fine-tuning, nor is it really an argument against design.  At best it is an argument against the argument for design, since it effectively says "all universes with intelligent observers in them would appear designed from the inside, no matter whether they were designed or not, so mere observation of apparent design does not constitute evidence of design (nor does it constitute evidence against design)".

And if fine-tuning of the universe is a necessity, the question arises as to why it is necessary.  Is it mere happenstance that the universe is necessarily the way it is, or is that by design?

There is an argument that is a combination between necessity and something else, in which the deepest laws establish fine-tuning in our universe.  But the provenance of those deepest laws then becomes the question; were they established by design or do they just happen to be that way?  This isn't really a separate argument, it's merely a pointless deferral of the argument.

Then there is denial.  Denial is difficult to maintain, since there are so many elements of the universe which appear to be fine-tuned.  Nevertheless, there have been some people who have argued that at least some of the claims regarding fine-tuning are bollocks (even I have dabbled: gravitational constant - claimed by WLC, the speed of light - claimed by Josh the Searcher).  There are papers that point out that one of Barnes' favourite examples doesn't hold water (fine-tuning of the strong force).  Vic Stenger wrote a book attacking many of the claims of fine-tuning.  But even if denial worked, we'd still be left with an appearance of design and we could ask questions about whether this appearance was due to chance, necessity or design.  If it was necessity, then this is no real argument against design and ends up resolving down to chance or design anyway, as alluded to above.

That leaves us with chance and design.  At the end of the day, there are only two fundamental answers to the problem of fine-tuning, either it is mere chance that the universe is the way that it is or it was designed that way.  And only one of those is an objection to design.

To be continued in Chance or Design?

Monday, 19 September 2016

Arguing Conscious Realism to Absurdity

Back in Fine Tuning Towards Ignorance, I presented a scenario in which a fat dormouse (Chubby Loir) was saved by a crack in a barn wall, because he could squeeze through, while Tiddles the cat could not.  I want to revisit that scenario in light of the notion of "conscious realism".  If conscious realism were true, then there would be no objective, observer-independent reality and my representation of reality could be different to your representation of reality.  Now I naturally think this is bollocks, but let's pretend that it wasn't bollocks.  Let's also anthropomorphise Chubby Loir and Tiddles to the extent that they become conscious agents (unnecessarily for most of us, I hope, since these beings have previously been given to very human-like thought processes, and consciousness is not necessarily limited to humans).

Imagine then that they are both particularly pessimistic in their outlook.  Chubby Loir has been sighted by Tiddles and thinks to himself: "Just my luck, I'm going to be eaten now, but I might as well attempt to survive, even though I know it won't be successful."  Tiddles thinks to herself:  "That's a tasty looking dormouse, I almost certainly won't catch it, but I've got nothing else on the agenda, so I'll have a go anyway."  And the chase begins, with both running half-heartedly towards the barn.

Now I don't know whether, in the "conscious realism" paradigm, our attitudes affect our subjective realities, but something apparently will so the pessimism of Chubby and Tiddles can stand in place of whatever the actual mechanism is that permits their realities to differ.

As they approach the barn, they both see a crack, but their subjective realities with respect to the crack differ.  Chubby sees that it is too small for him to wriggle through but Tiddles sees that it is wide enough for Chubby to run through easily, but far too small for her to follow.  So, we reach the absurdity.  Chubby stops, convinced that certain death will follow, because he can't get through the crack while Tiddles stops, and watches as Chubby runs through the crack and escapes.  So we'd have two contradictory "realities", one in which Chubby escapes and one in which Tiddles (who does not belong to Schrödinger, by the way) eats him.

Donald Hoffman, the author of this madness, might argue that in his conception of "conscious realism" beings evolve so as to achieve fitness which is not necessarily consistent with reality, and the scenario I describe is inconsistent with fitness because Chubby gives up on trying the crack and Tiddles fails to eat him.  But even if their perceptions of reality are consistent with a more optimistic fitness, we could still have Chubby seeing that he could get through the crack and escape and Tiddles seeing that the crack is sufficiently large for her to get through and slay Chubby.  Two contradictory realities again.

Of course, it is possible for either of them to make a mistake.  Chubby could misjudge the crack and end up stuck in there, with his enormous bottom poking out, ready for Tiddles to drag him out and devour him.  Or Tiddles could either misjudge the crack as too small when it wasn't or end up getting stuck there herself, so that she ends up getting munched on by a fox.  But in both of these cases, this was because their perceptions of reality were inconsistent with an actual objective reality.  And youtube is replete with "fail videos" in which people misjudge objective reality - in which their own personal subjective realities were wrong, and we can only say they were wrong because there were objective realities against which we can compare them.  The objective realities into which they ran face first, or against which they crushed their (usually) adolescent manhood, or onto which they painfully fell.

(I could only bear about two minutes of the last compilation linked, so I didn't watch the others - watch at your own peril.  While I'm clearly more empathetic than I normally let on, I note that a number of the victims were idiots who managed to hurt themselves with what appears to be some forethought and are, therefore, possibly prime candidates for judicial culling from the gene pool.  I'm hoping that there were no actual culling events recorded.)

Anyways, you could call this the YouTube Argument Against the Madness that is Conscious Realism.

You're welcome.

Sunday, 18 September 2016

The Ludicracy of Conscious Realism

It's sad to see that Quanta Magazine should take Donald Hoffman seriously when he waxes lyrical on the nature of reality, based on his "conscious realism".  This is a broadly respected repository of science journalism, but in this case, the editors appear to have let the article through because it mentions quantum stuff.

Naturally, I object to "conscious realism" in general, because it is total bollocks, but I also object some of the specific nonsense spouted by Donald Hoffman.  Now I would have provided a Wikipedia link to the page on "conscious realism" here, but there isn't one.  When you google the term, you end up at a document written by Donald Hoffman, which states:

Conscious realism is a proposed answer to the question of what the universe is made of. Conscious realism asserts that the objective world, i.e., the world whose existence does not depend on the perceptions of a particular observer, consists entirely of conscious agents.

Hoffman even gave a TED talk on the topic - Do we see reality as it is?

My major beef is with this specific claim (from the Quanta Magazine article, but also referred to in the TED talk):

Snakes and trains, like the particles of physics, have no objective, observer-independent features. The snake I see is a description created by my sensory system to inform me of the fitness consequences of my actions. Evolution shapes acceptable solutions, not optimal ones. A snake is an acceptable solution to the problem of telling me how to act in a situation. My snakes and trains are my mental representations; your snakes and trains are your mental representations.

I don't think I can state this strongly enough: This is total and complete bollocks.  It's lunacy.  I'd call it quantum nonsense, but this might lead some readers to think that it's nonsense on a minuscule rather than massive scale.

This idea could only work if, in order for trains to work, we were obliged to explain them to each other - to synch our individual subjective realities with respect to the trains in our shared experience.  Think about it for a moment.  Engineer E designs a train at the request of Customer C, who approves the drawings and passes them over to Manufacturer M.  At various stages during the process, Surveyor S visits the construction site and compares the train, in its current form, to the design detailed in the drawings.  Eventually, S signs off on the construction and M presents the train to C who then puts it onto a pre-existing rail network, with pre-existing tracks, pre-existing bridges and pre-existing tunnels and sets it off on its way.

There is certainly some discussion between E, M, S and C, but the process does not involve a word by word, squiggle by squiggle explanation as to what each of the pieces of paper have written and drawn on them.  For the information to flow accurately from person to person, and for a train to result which fits on the tracks and into tunnels (etc, etc), those pieces of paper (the drawings) must have an independent, objective and (at least temporarily) immutable reality.

Once the train exists, we don’t need to discuss with each other the location of doors and seats, and so on.  If my reality of the train could truly be different to your reality of the train, then we could enter via different doors and you could sit on a seat in a location that, in my reality, doesn't even exist on my train (for example, you might have the train as being four metres wide, whilst mine is only three metres wide).  Animals that cannot even converse with us (guide dogs for example) will reliably enter and exit via the doors in a train that must necessarily have an objective reality (and may not be perceptible at all by those being guided).  An objective reality is necessary because we could not synch any differences in subjective reality with them.  (Cross country horse events would be a nightmare if horse and rider could not independently observe an objective reality with respect to jumps and other obstacles - both need to be aware of what they are jumping over, and when, in order for them to move in concert and make the jump.)

I agree that there are certain aspects of reality that are fuzzy to us - colours vary due to lighting and there is evidence that the perception of some colours may be language dependent (Lenneberg and Roberts).  The idea is that given the lack of a specific word for "orange", speakers of Zuni find it more difficult to differentiate between two colours that an English speaker would have no difficulty distinguishing.  Females, who generally have a better handle on language, also have a greater range of colours that they can distinguish, despite not having any huge difference in their physiognomy.  (There are apps written for men to help them discuss curtain, cushion and dress colours with women - "What do you mean, the light green cushion?  It's not light green, it's chartreuse!")  There are a range of illusions that we may fall prey to: the illusion that an image on a page is 3D, if it is sufficiently well drawn, or the illusion that a spoked wheel is spinning in the opposite direction that it is actually spinning and so on.

However, these illusions and inaccuracies on our part as imperfect sensory creatures should never be taken to mean that reality is somehow "imperfect", let alone non-existent.  To pretend otherwise represents a monumental level of hubris.

To my mind, Donald Hoffman's "conscious realism" constitutes an equally monumental level of stupidity, complete with a massive begged question - where do these "conscious agents" of his come from, if there is no objective reality?  It's a form of quantum woo.

But then again, who knows, it might just be a misconception on my part.

Thursday, 15 September 2016

Metaphysical Necessity

Yesterday, I asked whether it is a strict logical possibility that William Lane Craig is a lying doofus.  Today, I want to ask whether it is a metaphysical necessity that William Lane Craig is a lying doofus.

Some may be sad to learn that I think that the answer is a resounding "No", but please stay with me as I try to explain how I reach this conclusion.

When reading the Wikipedia page on "metaphysicalnecessity", we immediately come across words that are faintly familiar:

In philosophy, metaphysical necessity, sometimes called broad logical necessity, is one of many different kinds of necessity, which sits between logical necessity and nomological (or physical) necessity.

Compare this with the words of WLC:

… The answer is “metaphysical possibility.”  This is a modality in between physical possibility and strict logical possibility and is often called “broad logical possibility” by contemporary philosophers.

So, it would appear that WLC took the notion of "broad logical necessity" (likely coined by Plantinga in The Nature of Necessity in 1974), twisted it into a new form, that being "broad logical possibility", and claimed that contemporary philosophers were already talking about it.  I saw the term "metaphysical necessity" in one of the very early documents that refer to "broad logical possibility", the transcript of a talk by … yep, William Lane Craig (The Coherence of Theism).

In this document, you can see evidence of the switch from "broad logical necessity" to the new term "broad logical possibility":

Furthermore, the modality operative in possible worlds semantics is not strict logical necessity/possibility, but broad logical necessity/possibility. Strictly speaking there is no logical impossibility in the proposition The Prime Minister is a prime number; but we should not want to say, therefore, that there is a possible world in which this proposition is true.

It is true that people have been talking about metaphysical necessity for a very long time, but what exactly do we mean by "people" here?  Most of these people have been theists talking about god, or talking about Saul Kripke (who in turn was talking about what was referred to in Strict Logical Possibility as "metaphysical possibility").  Again, when we try to consider things that fall into this category, now considered in terms of necessity, rather than possibility, we can find only one thing that is claimed to be "metaphysically necessary" - and that is a god, most specifically the god of the ontological argument.  There's a neat little Venn diagram on this page that sums things up nicely.

Let us put Kripke's modal logic tautologies aside (ie put aside notions similar to it being "metaphysically necessary" that water is H2O and vice versa (at which point we need to also put aside the confusion of people who don't accept that ice is also water, despite it having a different name and being a lattice rather than liquid form)).  Other than a god, what does anyone claim to be a "metaphysical necessity"?

When I first started developing the idea for what became Strict Logical Possibility, I was very much thinking about the awkward negation of "strict logical possibility".  People tend to get confused about how modals are negated and casual modern English (particularly as used by Americans) only makes the confusion worse.

For example, if I were to say that "not all" cats are grey, I am not suggesting direct opposite of "all cats are grey" - that is I am not say that all cats are not grey.  If I wanted to say that, I would say "no" cats are grey (or all cats are "not grey".  In clumsy usage, "all cats are not grey" is often meant to say "some cats are grey, but not all of them" - rather than "every single cat that exists is some colour other than grey".  (I'm somewhat ambivalent on the grey/gray divide, although I do see Gray as more of a surname than a colour.)

This confusion carries over to considerations of what is possible/necessary and not possible/necessary (see Plantinga and His BS5).  In brief that which is not possible cannot be necessary, but that which is not necessary can be possible.  In other words, a lack of necessity is consistent with both possibility and impossibility.  WLC does not fall into the trap of saying explicitly that the non-existence of god is metaphysically impossible, but others certainly do:

William L. Rowe has challenged my claim that there are only two kinds of impossibility, logical and physical, by introducing the concept of metaphysical impossibility — the impossibility which obtains just in case nothing has the power to bring about an individual’s non-existence — and by maintaining that, though God’s non-existence is metaphysically impossible, it does not follow that it is logically impossible as well.

And the ontological argument is based very much on the notion that the non-existence of the god in question is metaphysically impossible - which is to claim that the existence of god is metaphysically necessary.  WLC certainly makes the claim that the existence of his god is ametaphysical necessity:

(blah blah blah, blah blah) … Thus, it is metaphysically necessary that God exists.

But now we are back to the question of what things are metaphysically necessary - if there is nothing else than god in this category (and possibly all those tautological claims that things are the things that they are), then surely the claim that god is "metaphysically necessary" has no teeth whatsoever.  God would have the precisely the sort of "metaphysically necessary" existence that god has (which could easily be no existence whatsoever) and god would have the precisely the same characteristics that god has (being spaceless, timeless, immaterial and non-existent).

WLC goes on in the article linked above to write:

We have here the germ of the ontological argument for God's existence. For if it is possible that God exists, there is a possible world in which God has necessary existence. But then He exists in every world, including this one. Thus, the atheist is thrust into the awkward position of having to say that God's existence is impossible. It is not enough to say that in fact God does not exist; the atheist must hold that it is impossible that God exists—a much more radical claim!

He's claiming here that, because the atheist disagrees with the claim that the existence of god is a (metaphysical) necessity, she needs to hold that existence of god is a (metaphysical) impossibility - perhaps even to the extent that the non-existence of god is a metaphysical necessity.  This is a false dilemma built on a(n implied) begged question - buried in the fact that the only object that is asserted to have a metaphysically necessary existence is a god.  The atheist is quite entitled to allow that gods are a metaphysical possibility, whatever is actually meant by that, while holding that none actually exist (for reasons other than metaphysical necessity/possibility).

Finally, I did say that I did not want to claim that is a metaphysical necessity that WLC is a lying doofus.  I think it's quite reasonable to be averse to putting the assertion "god exists" on a par with "WLC is a lying doofus".  After all, I am quite convinced that god does not exist.