HRG

Sorry, your last lines do not make sense. "Before" and "until" are words which refer to time-ordering, thus "before time" is meaningless. Where exactly is "1000 km north of the North pole" ?

BTW, I submit that time and space do not have the "potential to not exist" (assuming that this concept makes sense, of which I am not sure).

Regards,
HRG.

Vorkosigan

The question raised in anthropic arguments is - why are the parameters of this universe such that fine tuning to them allows observers?

I've decided to explore this further...

Let's go back to my comment about the fish: FT is like the fish looking around at the ocean and saying how wonderful it is that the ocean suits them so well. If some FishPhilosopher responded that it could only be Design, Statistics or Coincidence, FishBiologists could only laugh, because they have a fourth option available; namely, they could give an account of events. In this case, that would be a story of biological evolution.

Similarly, if someone asked about the emergence of shoe manufacturing in New England after the American Revolution, nobody would answer "Design, Statistics or Coincidence." The proper response would be to give an account of the emergence of the industry.

Now, somebody asks "Why are the parameters such that the universe has an observer?" This is a nonsense question the way it is framed; it presumes teleology. It presumes some special explanation is required. The proper response is to give an account of the emergence of humans -- in this case, one of biological and sociocultural evolution (this account also explains why humans are interested in such questions), along with an account of how the parameters of the universe were formed. The second is currently not possible, although I expect progress in the next couple of decades.

There is no "WHY" question here, the only real question is a "HOW" question. There's nothing especially interesting about the universe having an observer, any more than there is anything especially interesting about it having beautiful lightning storms on Jupiter, or black holes or cornflakes. One could ask this "WHY" question of any object in the universe; and the answer would always be the same: give an account of its history. "WHY" questions are meaningful only to the extent that they are "HOW" questions. When they embrace teleology, they become meaningless, because they apply equally to any object in the universe.

Thus, the anthropic principle, weak or strong, is meaningless. It states that there is something inherently special that requires an inherently special explanation about the universe having observers. But the emergence of humans is already explained by the theory of evolution; no special explanation is required. Anyone who posits the anthropic principle must explain why a special explanation is required for observers, and not for rocks, stars, solar systems and everything else in the universe.

The usual response is to claim that the emergence of observers is low in probability, and so requires special explanation. There are three major problems with this view. First, there are lots of things that exist in a range of conditions much narrower than that of living observers. Second, nobody knows the probability of intelligent observing life emerging on any particular planet or in any particular universe. (My gut feeling is that it is high, based on the existence of several creatures in the genus Homo who were apparently capable of such observations, and possibly other creatures such as dolphins). The third is that "low in probability" is merely a subjective and essentially unfounded definition, a value -- why should "low in probability" be the criterion for the anthropic principle's requirement of special explanation, and not "red in color" or "made of C02?"

Yet another response is to argue that somehow observers are more complex than other things, so we require special explanation. Again, we face the problem -- "Complexity" as a criterion is a value; why was it selected and not another? Again, we already have an explanation for complexity, called evolution, so why is a further explanation required? And of course, there are things more complex than us -- for example, any system that includes us. Why is "complexity" limited to single species, and does not take into account interactions among species? Surely Gaia is more complex than we are. Again, we are looking at arbitrary and subjective values.

Vorkosigan

beausoleil

Yes, but the fine tuning to the parameters of this universe resulted in observers, whereas that in other universes wouldn't have.

You know this how.....?

We don't know this, it's one current working hypothesis. But if you think a universe with nothing but hydrogen and helium would produce any chemistry able to support, say, a fish equivalent, go ahead and show us how. Our best understanding is that natural selection needs at least some 'interesting' chemistry to produce anything.

I think, if I may, that I do get your argument. On the other hand, I don't think you've understood mine. In fact, I don't think you've understood the anthropic principle.

If you prefer, you can think of it as a question about what determines the values of the parameters in a universe. We don't know. Maybe they arise naturally in some way that doesn't just move the argument to the source of the parameters that determine the set we're worrying about. Maybe they are random and there is a multiplicity of universes

To pursue your fish argument and show why your 'give an account' response won't do - let's pretend that the fish, being fish, have no knowledge of the universe beyond the solar system. The fish planetary scientist would turn to the fish biologist and point out that, if their planet was slightly further away from or nearer to the sun there would be no ocean. There would then be no fish. The fish astronomer (who mostly studies Mars, I guess) might then say, we have three logically possible explanations according to the fishopic principle -

1. this is the only solar system and and it was designed for fish
2. this is the only solar system and it's pure chance - not worth thinking about.
3. there are lots of other solar systems out there, so the odds are that at least one of them would have an ocean - once there's an ocean, the production of something like fish looks pretty likely by our current understanding.

The fish fundamentalists would then run away screaming that the fish astronomer has admitted the planet was designed for them - so there was a God after all, while their fish antagonists would run in the opposite direction screaming that the whole thing was both meaningless and teleological at the same time (somehow) - even though only solution 1 is in fact teleological and the so-called meaningless principle has already been shown to have predictive force. That any planet would appear fine tuned to whatever was on it so the whole thing was rubbish. Or they might say they expect a theory in the next few decades that would give an account of events that will explain why all suns would have a planet with water, that it couldn't be otherwise - a variant of option 1, actually. Or they'd ask why fish should be singled out and not, say, seaweed or moules marinieres (to which the fish astronomer would respond that this was a strawman - he didn't much care what you singled out, since it was all just a stand in for the idea that there was a planet that could support liquid water - so let's call it the barnacle principle if you like.)

We, as outside observers, know that the solution was that there are lots of suns with planets so the odds of at least one with an ocean are quite high. Once there's one with water, we think we can give an account of events that leads ultimately to fish or a fish equivalent. Thus the confidence of the fish anti-fundamentalists that a theory would explain why all suns would have a planet that formed an ocean was misplaced.

The anthropic principle gets confused a lot - the fish question is why is there a planet with liquid water - it gets dressed up as why is there a planet fish can live on, but it comes to the same thing since we have an account of events leading from ocean to fish. It's just that it's easier to explain to fish who know what a fish is but have only a vague notion of the scientific ideas about the ocean.

Replace fish with us. and the solar system with the universe, and that's all there is to the anthropic principle. There are good books out there that don't get sidetracked into metaphysics, if you look for them.

The likelihood of intelligence arising on a planet given the set of parameters in our universe is a completely different debate - but one current resolution of Fermi's paradox is that it is in fact quite unlikely even once life has arisen. Clearly (for anthropic reasons, actually) the evolutionary record on Earth is not a reliable source of data - what we can get are ideas of contingent probabilies of trait z arising (eg eyes) once trait y has already arisen (y determined by the earliest common ancestor of all things that have eyes - I don't know what that is, alas). And this is limited to cases where the same solution emerged separately several times. To the best of our knowledge intelligence only arose once.

[ July 13, 2002: Message edited by: beausoleil ]</p>

eh

Where does he say anything contrary to my post? Again, please actually understand the material before posting about it.

I thought I just said that?


Read that sentence you just wrote over again. Do you not see the problem with before time existed? Think about it.

Vorkosigan

Yes, but the fine tuning to the parameters of this universe resulted in observers, whereas that in other universes wouldn't have.

You know this how.....?

We don't know this, it's one current working hypothesis. But if you think a universe with nothing but hydrogen and helium would produce any chemistry able to support, say, a fish equivalent, go ahead and show us how. Our best understanding is that natural selection needs at least some 'interesting' chemistry to produce anything.

I never claimed every universe of any form would produce intelligence. Only that we don't know what the odds are for other kinds of universes -- presumably complex universes, of course.

On the other hand, I don't think you've understood mine. In fact, I don't think you've understood the anthropic principle.

I understand it very well, thank you. As we shall see below, someone here is confused, but it isn't me.

If you prefer, you can think of it as a question about what determines the values of the parameters in a universe.

Then it's not an anthropic principle, is it? It is merely a HOW question about physics.

1. this is the only solar system and and it was designed for fish
2. this is the only solar system and it's pure chance - not worth thinking about.
3. there are lots of other solar systems out there, so the odds are that at least one of them would have an ocean - once there's an ocean, the production of something like fish looks pretty likely by our current understanding.

The fish fundamentalists would then run away screaming that the fish astronomer has admitted the planet was designed for them - so there was a God after all, while their fish antagonists would run in the opposite direction screaming that the whole thing was both meaningless and teleological at the same time (somehow)

You seem to have misread again.

- even though only solution 1 is in fact teleological and the so-called meaningless principle has already been shown to have predictive force.

Where? Design has no predictive force; it is compatible with any universe.

That any planet would appear fine tuned to whatever was on it so the whole thing was rubbish.

False. Again, this is not what I said. It would appear Fine Tuned only if it ran on selection processes operating under natural laws. I do not know how other types of universes would appear.

Or they might say they expect a theory in the next few decades that would give an account of events that will explain why all suns would have a planet with water, that it couldn't be otherwise - a variant of option 1, actually.

This isn't what I said -- what a surprise! -- I expect physics to tell us why things are as they are eventually, not that it couldn't be otherwise. The Design crowd is the one arguing that it couldn't be otherwise, remember?

...moules marinieres (to which the fish astronomer would respond that this was a strawman - he didn't much care what you singled out, since it was all just a stand in for the idea that there was a planet that could support liquid water - so let's call it the barnacle principle if you like.)

But that's not the anthropic principle you proposed earlier. You chided me before because you were complaining about me not thinking about observers -- now you've suddenly adopted my position that it applies to any object in the universe. Which totally refutes it as a principle that applies to observers. That's not the anthropic principle YOU proposed earlier:

• The anthropic principle is about what the universe must be like to allow the existence of observers and how likely it is that any universe would have those properties.

If it now applies equally to every object in the universe, then it is certainly not a principle that is based on observers and their likelihood of existence. Given your evident confusion, your sarcasm in your post is entirely unwarranted.

Again you said:

• Exactly, but you're criticising the anthropic argument which is based on the existence of observers, not on the appearance of fine tuning.

Your most recent formulation of this is like saying if your mother hadn't met your father, you wouldn't be here. True, but not very interesting. The problem with this formulation of the Anthropic principle is that it not only applies to any object in the universe, but to any uniquely contingent event or object in history for which we as yet have no clear explanation.

The likelihood of intelligence arising on a planet given the set of parameters in our universe is a completely different debate

Again, that's not what you said above. You linked them intimately:

• The anthropic principle is about what the universe must be like to allow the existence of observers and how likely it is that any universe would have those properties.

It is not a different debate, but a most important aspect of this one. However, you seem to have adopted my position above that the question applies to any object in the universe, so I assume you no longer accept the Anthropic Principle as valid (since you have given up the idea of observers as requiring special explanation).

- but one current resolution of Fermi's paradox is that it is in fact quite unlikely even once life has arisen.

Yes, that's one current resolution. There are many others.

To pursue your fish argument and show why your 'give an account' response won't do -

But, unfortunately, it will do. As soon as we have the naturalistic explanation for the emergence of these parameters, linked with our already-existing account of human evolution (or whatever object you've set your sights on), then that will be it. The Anthropic Principle will be finished because we will have an account of reality. Ultimately, it is a god-of-the-gaps argument, interesting currently only because we don't know how the parameters were determined.

We could play the Anthropic Principle Game with Earth (and the ancients did). Look how perfect Earth is, just this temperature and just that gravity, etc, etc, etc. But no thinking person would accept that -- why? Because we have an account of Earth history and the evolution of life that completely explains the Anthropic Principle with respect to planet Earth. Now that we have this account, nobody but a few religious believers thinks the Earth and life was "designed." All believers did was push it back to the next level, the universe: "OK, you bastards, you've explained the Earth, but try THIS ONE!"

Your claim seems to amount to saying that even if we had an account of the universe and its origin, the Anthropic Principle would still be justified. And that is self-evidently absurd. As soon as the physicists explain why certain things turned out the way they did, BOOM! The Anthropic Principle will be DOA.

Of course, you said that yourself that if we have an account, it is enough, right here in your response:

We, as outside observers, know that the solution was that there are lots of suns with planets so the odds of at least one with an ocean are quite high. Once there's one with water, we think we can give an account of events that leads ultimately to fish or a fish equivalent.

So, here you have just argued that where one is able to give an account, the Anthropic Principle no longer applies. Which, come to think of it, is precisely what I said in my last post. Again you're agreeing with me while attempting to refute me. Are you sensing a pattern here?

Thus the confidence of the fish anti-fundamentalists that a theory would explain why all suns would have a planet that formed an ocean was misplaced.

I never said anything even remotely like this. At no time have I ever said that I expected that all universes would have intelligent life.

Vorkosigan

[ July 13, 2002: Message edited by: Vorkosigan ]</p>

beausoleil

[QUOTE]Originally posted by Vorkosigan:

But that's not the anthropic principle you proposed earlier. You chided me before because you were complaining about me not thinking about observers -- now you've suddenly adopted my position that it applies to any object in the universe. Which totally refutes it as a principle that applies to observers. That's not the anthropic principle YOU proposed earlier:


In fact I pointed out a few posts back that the anthropic principle works with paperclips. Where you're going wrong is in distinguishing only two options - observers or everything. What I'm saying is that anything that requires the same set of parameters as observers will do. In the case of the fish argument, everything that requires an ocean - fish, barnacles, moules marinieres.

If it now applies equally to every object in the universe, then it is certainly not a principle that is based on observers and their likelihood of existence.


It doesn't apply equally to every object in the universe - it applies equally to every object in the universe requiring the same parameters as observers. For example, a much wider set of parameters for universes will produce protons than will produce carbon nuclei.

Exactly, but you're criticising the anthropic argument which is based on the existence of observers, not on the appearance of fine tuning.

OK - I should have said observers and anything else produced from the same parameters as observers. I genuinely thought it was obvious.

The likelihood of intelligence arising on a planet given the set of parameters in our universe is a completely different debate

Again, that's not what you said above. You linked them intimately:

No. Let me distinguish -

1. Possibility of intelligence arising somewhere in a universe. Depends on fundamental physical laws of said universe. (Intelligence being shorthand for intelligence and other things made possible by the same parameter set.) Assumptions of this sort: universes that don't get beyond helium don't produce intelligence - it is impossible. Note in passing that a universe with helium would look as if it were finely tuned to produce helium - there is thus some form of 'selection' anyway - but that the degree of tuning is less than that to produce carbon.

2. Given fundamental laws of a universe that allow intelligence to be possible - probability of intelligence in any given solar system.

The anthropic principle is about what the universe must be like to allow the existence of observers and how likely it is that any universe would have those properties.

Once again, I was using 'observers' as shorthand. I was pointing out that universes that can produce observers (and other things) are as far as we know a small subset.

We could play the Anthropic Principle Game with Earth (and the ancients did). Look how perfect Earth is, just this temperature and just that gravity, etc, etc, etc. But no thinking person would accept that -- why? Because we have an account of Earth history and the evolution of life that completely explains the Anthropic Principle with respect to planet Earth. Now that we have this account, nobody but a few religious believers thinks the Earth and life was "designed."


The bit you're overlooking in this account - and you really are overlooking it - I know it's hard to believe - is the part that says, to the best of our knowledge, the formation of planets that can support life is unlikely.

There is not a mechanism to produce Earth-like planets. The solution is not that we have an account requiring one to form or that it is produced inevitably by natural selection, but that there is a statistical distribution of planets some of which do have the right properties. This, combined with an account of origin and evolution of life through natural selection on planets with the right sort of properties, constitutes our rebuttal of the design argument applied to the planet Earth. But both bits are necessary.

And this is the concept you seem to be having trouble with.

In response to the question about where the anthropic principle has had predictive force, I suggest you read something about carbon synthesis in stars - Hoyle predicted the presence of a nuclear resonance from the observation that there was carbon (and thus that he could be there).

This isn't what I said -- what a surprise! -- I expect physics to tell us why things are as they are eventually, not that it couldn't be otherwise.

Unless physics tells us that they couldn't be otherwise, the anthropic argument (as used by scientists and not creationists) will still apply. Can we deduce from the existence of a universe that can support life that there are a large number of universes.

Physics provides us with a reasonable account for how the Earth formed and how it has been capable of continuously sustaining life. This process is sufficiently convoluted that, if there were only 10 planets, the chances of there being one that could support life over billions of years would be minute. Were there not a whole universe of other solar systems out there, the design argument would be looking pretty good. Or do you have some other explanation in that thought experiment?

Vorkosigan

In fact I pointed out a few posts back that the anthropic principle works with paperclips. Where you're going wrong is in distinguishing only two options - observers or everything.

That's where you're misreading me. How surprising. I have clearly said that it applies to any object in the universe. I haven't said that I've sorted the universe into two things, observers and everything else. That's what you've been doing....and in fact will do below.

What I'm saying is that anything that requires the same set of parameters as observers will do. In the case of the fish argument, everything that requires an ocean - fish, barnacles, moules marinieres.

No, that isn't correct. There's no reason, other than cognitive bias built into humans, to select observers as the really interesting thing that requires explanation. Further, why haven't you selected something that has an even tighter parameters than life does? The Anthropic Principle subjectively assumes that there is something special about observers (or equivalent) that demands an explanation. There's no reason to select observers out of any other object in the universe. Or things with the same parameters as observers.

Now you've simply sorted the universe into two classes, those things that require X parameters and those that don't -- which you just accused me of doing. I love it when you do what you criticize me for.

Why did you select those parameters and not others?

It doesn't apply equally to every object in the universe - it applies equally to every object in the universe requiring the same parameters as observers. For example, a much wider set of parameters for universes will produce protons than will produce carbon nuclei.

But the range of parameters is irrelevant, for some wandering superbeing can go by and say "Hey, look how perfectly that universe suits carbon nuclei! It's probably designed....." Like I said, any universe that runs on natural law will appear Designed.

Again, why did you not select a much tighter range of parameters?

OK - I should have said observers and anything else produced from the same parameters as observers. I genuinely thought it was obvious.

It wasn't obvious, and now you've created an even worse problem. Why did you select observers, and not anything with an even tighter range of parameters?

Of course, this presumes that you actually know that the range of parameters that can produce observers is small. Which you do not. You only know the range of parameters that can produce observers like us appears to be small (but may not be).

Once again, I was using 'observers' as shorthand. I was pointing out that universes that can produce observers (and other things) are as far as we know a small subset.

C'mon, you don't know that. We don't know anything about other universes. Perhaps every universe is as complex as ours. Perhaps they are not. You don't know. This argument is unsupported. Do you know of any other universes?

The bit you're overlooking in this account - and you really are overlooking it - I know it's hard to believe - is the part that says, to the best of our knowledge, the formation of planets that can support life is unlikely.

1) Irrelevant, because we have an account of how earth formed, and there is nothing in the slightest supernatural about it. As I said.

In fact we know that the probability of a universe having life is 1. For all we know, every universe is like ours. We have no data, so can make no claims.

2) There's no way that know what the probability of the formation of life is for any given planet. Certainly life like ours could not survive on Pluto or on any of the planets discovered to date. Some other form of self-replicating system may well be possible.

3) For crying out loud, why is "life" the problem you've placed at the center of this principle? What is the a priori reason you've picked it out? The Anthropic Principle is entirely subjective.

There is not a mechanism to produce Earth-like planets. The solution is not that we have an account requiring one to form or that it is produced inevitably by natural selection,

I NEVER claimed EVER that we needed an account requiring one. Only that when we had an account, the Anthropic Principle no longer applies. I do not know why you keep repeating this point as if you are correcting me. I NEVER made this claim.

.... but that there is a statistical distribution of planets some of which do have the right properties. This, combined with an account of origin and evolution of life through natural selection on planets with the right sort of properties, constitutes our rebuttal of the design argument applied to the planet Earth. But both bits are necessary.

And this is the concept you seem to be having trouble with.

Seems to me it is what I've been saying. Like in my last post, for example.

In response to the question about where the anthropic principle has had predictive force, I suggest you read something about carbon synthesis in stars - Hoyle predicted the presence of a nuclear resonance from the observation that there was carbon (and thus that he could be there).

Hoyle predicted that, based on the existence of living things, carbon had to be synthesized just so inside stars. A brilliant insight, but it's like deducing from glass and metal in the road that there must have been a car accident. This is not evidence of the predictive force of the Anthropic Principle, but a simple deduction that no one had made before. It's a common deduction path in science to see a consequence and deduce an antecedent cause or condition, such as when Planet B is discovered through perturbations in the orbit of Planet A. Hoyle can label it what he pleases, and so can you, but the Anthropic Principle was not at risk there. If his prediction had failed, we'd still be having this discussion. This is because the AP has nothing to with science or logic, and everything to do with our cognitive biases.

Unless physics tells us that they couldn't be otherwise, the anthropic argument (as used by scientists and not creationists) will still apply.

Here's a thought experiment: Naturalistic cosmology explains everything -- the origin of the Big Bang, the origin of the parameters, etc. What happens to the Anthropic Principle? &gt;POOF!&lt;

Can we deduce from the existence of a universe that can support life that there are a large number of universes.

In the science that I was taught, you can't deduce anything from a population of 1. So far, all the universes we know support life. What can we deduce from that? Nothing that I know of.

Physics provides us with a reasonable account for how the Earth formed and how it has been capable of continuously sustaining life. This process is sufficiently convoluted that, if there were only 10 planets, the chances of there being one that could support life over billions of years would be minute.

Yes, and if your mother hadn't met your father, you wouldn't be here.

You keep saying "life" as if ours were the only kind possible. What are you going to do if we discover life on another planet in our solar system.

Were there not a whole universe of other solar systems out there, the design argument would be looking pretty good. Or do you have some other explanation in that thought experiment?

If ours were the only solar system, Design would be a lock. If my mother hadn't met my father....

Vorkosigan

luvluv

eh:

I think we are dealing more with the limitations of language than the limitations of science. We are essentially playing a semantic game. We have no language to describe "a time when" time did not exist. But, Hawkings established in his work that there was such a "time". Since time itself was an effect, we don't have the language to describe, in temporal terms, what was "before" time. But nevertheless, there was a "time" when time did not exist.

I was simply asking how the notion of the universe's emergence through a quantum fluctuation is possible given that a quantum fluctuation requires time which did not exist until the universe came into existence.

What you are engaging in is an interesting exercise in linguistics but it is probably not anything a physicist would accept as an explanation.

eh

Because by defintion, there is no such thing. It's only a matter of semantics for those who wish to impose a deity who is somehow outside time yet able to do actions.

Oh really? Did he? Where? I think you are just confused with something you've read. But please do reference a link or book where he says what you claim.


Here, you are confused with something else. Many have said that the universe may have emerged as a quantum fluctuation from the vacuum, and inflation is included. But this is just a case of being sloppy with the english language. What they mean is the 'visible universe' emered from such a state. With inflation theories, our visible universe emerged from an area far smaller than a proton, but the rest of the universe is much larger.

Interesting. Let's see what Hawking wrote on the matter. From the Universe in a Nutshell:

In general relativity, on the other hand, time and space do not exist independently of the universe or of each other. They are defined by measurements within the universe, such as the number of vibrations of a quartz crystal in a clock or the length of a ruler. It is quite conceivable that time defined in this way, within the universe, should have a minimum or maximum value—in other words, a beginning or an end. It would make no sense to ask what happened before the beginning or after the end, because such times would not be defined.

Perhaps you are thinking about his theory where he views the universe like a globe. In such a model, the universe does not have a beginning or end, but just IS. The beginning of time, is just a point of reference. Much like we have a north and south pole on the globe, we have a beginning and end point. To ask what came 'before' or 'after' is the same as asking what is north of the north pole. So Hawking does not support the idea that there is some cause 'north' or before the big bang. Is it sinking in yet?

beausoleil

Sorry, been travelling for a couple of days. A few answers at random.

But first, you seem to think that in defending anthropic arguments I'm defending something supernatural. This is what makes me think you don't really know what anthropic arguments are. As if all you know about evolution were gained from YECs - so obviously you'd think it was rubbish.

If ours were the only solar system, Design would be a lock. If my mother hadn't met my father....

Hardly analogous. Here's the way it works.

Once a suitable planet exists, natural selection can explain humans.

That a suitable planet exists was thought to be a result of design (as you pointed out).

That a suitable planet exists is actually explained by there being a large number of planets with a variety of properties.

This latter is part of an anthropic argument of the bass-ackwards variety. What exactly is wrong with it?
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Here's a thought experiment: Naturalistic cosmology explains everything -- the origin of the Big Bang, the origin of the parameters, etc. What happens to the Anthropic Principle?

An origin producing many universes + selection of this one by the need for our existence is one candidate explanation. Your position, as I understand it, is that you already know it's not right.
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In the science that I was taught, you can't deduce anything from a population of 1.

Then I'm afraid your science education was incomplete. Perhaps what they meant was that you can't deduce a general principle from one example, which is true. In fact, anthropic arguments try to show us cases where you can't infer a general principle even from lots of consistent results.
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I NEVER claimed EVER that we needed an account requiring one. Only that when we had an account, the Anthropic Principle no longer applies. I do not know why you keep repeating this point as if you are correcting me. I NEVER made this claim.

I keep repeating it precisely because you seem to think that 'the Anthropic Principle' no longer applies. This is not correct. 'The' (more properly 'an') anthropic principle is part of the argument in this case.

When you say the anthropic princple no longer applies, you are in fact saying that the planet we observe is randomly selected from all planets. That Earth is typical, not of planets sustaining multicellular life or life or intelligent life or life with wings, but of all planets erverywhere. You might not intend this, but that's what the words mean. That's why I keep repeating this point.

In fact, the anthropic principle is a fancy way of reminding us that inferences we make from our observing position are not random samples of the universe (or universes).

1) Irrelevant, because we have an account of how earth formed, and there is nothing in the slightest supernatural about it. As I said.


There's nothing supernatural about an anthropic argument - why do you think there is?

In fact we know that the probability of a universe having life is 1. For all we know, every universe is like ours. We have no data, so can make no claims.

(I assume you mean 'the universe having life' - since 'a universe...is 1' makes no sense.)

Before moving on to the the substantive point, I'd like to point out that you're confusing probabilities before and after the fact. Before I toss a coin the probability of heads is 0.5, after it has fallen heads it is 1. At some early time by which the parameters were set, we think the probability that our universe would develop life was high, whereas we now know that the probability of life in the universe is 1.

Back to the issue, your problem here is that you think the anthropic principle applied to the universe makes a claim. All it does is describe our knowledge at present of how the universe formed and note that it need not be representative of the universe formation process, just as the events in the origin of the Earth are not all representative of the planet formation process.

(2 is not relevant)

3) For crying out loud, why is "life" the problem you've placed at the center of this principle? What is the a priori reason you've picked it out? The Anthropic Principle is entirely subjective.


'supporting intelligent life' (to the best of our knowledge) selects a subset of universes with certain properties. We can only exist in one of these.

It is a selection principle - the anthropic principle reminds us that our planet is not typical of planets. It makes us wonder if our unvierse is typical of universes. Musings from there onwards try to account for the exitence of a universe that can sustain life. In these musings, the parameters don't rely on life/observers per se.

Of course, this presumes that you actually know that the range of parameters that can produce observers is small. Which you do not. You only know the range of parameters that can produce observers like us appears to be small (but may not be).

To the best of our current knowledge it's small. Best we can do. That's science, I'm afraid.

That's where you're misreading me. How surprising. I have clearly said that it applies to any object in the universe. I haven't said that I've sorted the universe into two things, observers and everything else. That's what you've been doing....and in fact will do below.

'Misreading' - pot - kettle. I'll use the argument about planets since it's clearer. Anthropic principle arguments tell us that our planet is not typical of planets since it supports us - this doesn't endow us with mystical status. Clearly the features that allow it to support us allow it to support other things - tigers, steel mills, headlice. When we specify what those parameters are, we are specifying them for all these things - we then seek an account for the existence of a planet with these parameters.

In the case of the universe, I don't choose something that requires an even tighter range of parameters because the requirement for it to exist doesn't restrict (statistical sense, not causation) the possible results of observations I make.

Lots of planets support ice - so the parameters that support us are a subset of those that support ice. I was pointing out that you don't allow any continuum. It is not true that exactly the same range of parameters allow us to exist as allow stars to exist.

Observers are the interesting thing about anthropic principles in general because the principles deal with the generalisability of observations and hence of theories deduced from them.