10 ms·

The Anthropic Principle (2000)

51 points by lainon 10y ago

bo1024 10y ago
Not complete without mention of Terry Pratchett: > The UU Professor of Anthropics had developed the Special and Inevitable Anthropic Principle, which was that the entire reason for the existence of the universe was the eventual evolution of the UU Professor of Anthropics. > But this was only a fomal statement of the theory which absolutely everyone, with only some minor details of a `Fill in name here’ nature, secretly believes to be true.
- jzl 10y ago
  One of my favorite Terry Pratchett quotes is from a typical hilarious character of his pondering the nature of the universe: "Then there was the question of why the sun came out during the day instead of at night when it would be more useful."
posterboy 10y ago
> [is to observe and understand the universe] a lucky break for the intelligent beings that they exist at all? If we were so intelligent, we wouldn't have to ask, so the answer is 42.
edgarvaldes 10y ago
>The Final Anthropic Principle states that once the Universe has brought intelligence into being, it will never die out. How can you propose someting like that? I mean, in a scientific way.
- AnimalMuppet 10y ago
  You can't. You propose it in a philosophical or mystical way - as completely unfounded speculation, not as science.
- deleted 10y ago
  [deleted]
- vorg 10y ago
  The Final Anthropic Principle follows naturally from the Weak/Strong Anthropic Principle. Once intelligence has evolved and observed the Universe with a single first thought, why didn't it then die out? Of course the definition of Intelligence is arguable, anything from a vaguely self-aware rodent to a literature-reading human, and beyond. If we take some person called Ubuntu who discovered how to control fire 130,000 years ago at age 23 years and 7 months in southern Mozambique as having the very first aware thought, then straight afterwards there'd be no more anthropic principle at work causing intelligence to exist in the Universe. The fact we're still here, our small tribe of sole humans not eaten by hyenas or our planet not extinguished by nukes, suggests there could be a Final Anthropic Principle at work.
  - yequalsx 10y ago
    I don't understand how this question is relevant: "Once intelligence has evolved and observed the Universe with a single first thought, why didn't it then die out?" What proof, line of reasoning, logical principle, or evidence do you have to believe that a single first thought would lead to anything dying out? What makes you think there is some underlying Anthropic Principle at work in the universe? Saying something could be at work is more or less saying "God did it". It doesn't explain or illuminate anything.
    - vorg 10y ago
      It only takes a single first thought by an intelligence to observe the Universe. Everything occurring up to then (e.g. nucleii, carbon, brains) is highly unlikely and therefore many people suggest an Anthropic Principle to explain it. Once that single first thought by an intelligence has occurred, the Weak or Strong Anthropic Principle is no longer required to explain the existence of intelligence, and so its continuance has the same unlikeliness as other life forms, i.e. ultimate extinction. The fact humans became the opposite of extinct (e.g. fire, scrolls, nukes) suggests that if the Anthropic Principle applies to the emergence of intelligence, something even "stronger" such as the Final Anthropic Principle could apply to the continuance of intelligence. I'm not saying there's an underlying Anthropic Principle in the Universe. I'm answering the question to show that the Final Anthropic Principle is as scientific a proposal as anything else.
- DonaldFisk 10y ago
  Frank Tipler is the main person proposing this, and he wrote about FAP in The Physics of Immortality: https://www.amazon.com/Physics-Immortality-Modern-Cosmology-Resurrection/dp/0385467990 https://www.amazon.com/Physics-Immortality-Modern-Cosmology-... Here's a review: http://www.fourmilab.ch/documents/tipler.html http://www.fourmilab.ch/documents/tipler.html And here's a quote from it: "it would be possible for each male to be matched not merely with the most beautiful woman in the world . . . but to be matched with the most beautiful woman whose existence is logically possible." verifiable here: http://articles.chicagotribune.com/1994-11-30/features/9411300040_1_frank-j-tipler-omega-point-universe http://articles.chicagotribune.com/1994-11-30/features/94113... I have his previous book, co-written with John Barrow, The Anthropic Cosmological Principle. It's taken more seriously.
elorant 10y ago
That web site seems like it popped-out from 1997.
- kardos 10y ago
  Last-Modified: Fri, 19 May 2000 20:30:18 GMT Not a bad guess!
AnimalMuppet 10y ago
> The Participatory Anthropic Principle states not only that the Universe had to develop humanity (or some other intelligent, information-gathering life form) but that we are necessary to it’s existence, as it takes an intelligent observer to collapse the Universe’s waves and probabilities from superposition into relatively concrete reality. This is a misunderstanding of what quantum waveform collapse is. It requires an "observation", but not an intelligent observer. For example, in the Schrodinger's Cat thought experiment, the Geiger Counter is a perfectly valid observer.
- ewzimm 10y ago
  I think you hit on the critical point where this theory goes awry, which is the idea that there is something special about human or animal intelligence which puts it in an entirely different category of other types of information gathering and synthesis. Another option is that the way people gather and synthesize information is just an advanced form of the same processes common to other dynamic systems, localized in layers of biology to create extreme forms of self-referential analysis. It's been a long debate, but the development of artificial intelligence is likely to significantly change the dominant perspective. If we continue to create ever more complex systems that behave intelligently but don't have the same kind of self-awareness as people perceive, we might be able to untangle the concepts of perception, intelligence, creativity, and the sense of self.
- ggreer 10y ago
  What's the criteria for what counts as an observer? Geiger counters are, but some photon detectors in a delayed choice quantum eraser experiment[1] aren't? 1. https://en.wikipedia.org/wiki/Delayed_choice_quantum_eraser https://en.wikipedia.org/wiki/Delayed_choice_quantum_eraser
  - akvadrako 10y ago
    Basically there is no sharp division, but the more the observation spreads, the harder it is to reverse. For one isolated particle, it's easiest. Anything we can reliably read is basically permanent, like a bit flip in a computer. So once a photon is detected, like by making a mark on a screen or camera, it's permanent. In the delayed-choice experiment this happens twice, once for the "interference pattern" and again after the choice. If you accept that, which I think is intuitive, then it makes the DCQE much easier to grasp. If you want to understand the experiment better, I would recommend this thread: https://www.physicsforums.com/threads/who-is-puzzled-by-the-delayed-choice.402497/ https://www.physicsforums.com/threads/who-is-puzzled-by-the-...
AnimalMuppet 10y ago
To state the Weak Anthropic Principle in a form that feels (at least to me) less like philosophical woo: "Universes that cannot be inhabited by intelligent observers are never observed, because there cannot be anyone there to do the observing".
- SomeStupidPoint 10y ago
  You just stated it as the contrapositive: "NOT Universe can support intelligent life -> NOT Universe can be oberved" ... rather than ... "Universe can be observed -> Universe can support intelligent life (-> Universe has values which can support life)" I'm not sure either is more useful than the other.
  - AnimalMuppet 10y ago
    Right. But the way it was stated in the article makes it easy to think of it as the universe requiring rather than the observer requiring. The other versions explicitly get into that kind of nonsense; I wanted to state the weak version in a way that made it clear that it didn't go there. (I suspect that this page states the weak version in that way in order to make the other versions seem more similar.)
    - SomeStupidPoint 10y ago
      Fair point.
    - jwatte 10y ago
      An /observed/ universe requires conditions to cause observers to evolve. I don't but that an "intelligent" observer is needed to collapse the waveform, BTW. That uses a very non-physical interpretation of "observer." Any particle that can absorb information, can be said to be "observing." As simple as a reaction that depends on temperature would do it.
      - deleted 10y ago
        [deleted]
jzl 10y ago
Also relevant: Boltzmann Brains https://en.wikipedia.org/wiki/Boltzmann_brain https://en.wikipedia.org/wiki/Boltzmann_brain A Boltzmann Brain is (very roughly) a "brain", i.e. self-aware entity, that appears spontaneously in the middle of the universe due to random quantum fluctuations. In an infinitely old and infinitely large universe this should actually be a common occurrence. So why are we not Boltzmann Brains ourselves? Why are we all here observing the universe clustered together on this one planet a mere 15 billion years since it came into being? Why is there so much structure?
- zardo 10y ago
  >Why is there so much structure? Because complex structures (brains) are much more likely to form out of self-assembling sub-structures than from random noise. And Boltzmann brains wouldn't be on hackernews.
- acqq 10y ago
  > In an infinitely old and infinitely large universe this should actually be a common occurrence. So why are we not Boltzmann Brains ourselves? Our Universe of 13.8 Billion years (think: just 13.8 G years -- my fingernail-sized camera card has more bytes than that number) is infinitely younger than an infinitely old Universe.
  - akvadrako 10y ago
    A year is a lot larger than one byte.
  - jzl 10y ago
    I didn't word my post very well (I posted the "infinitely old" comment), but what I meant was that it should be more likely to be a Boltzmann Brain in an infinitely old universe than a human standing on Earth in a ~14 Billion year old universe. So why are we the latter rather than the former? That's basically what the anthropic principle is all about. The fact that we are the latter tells us a lot about how the universe, or universes as the case may be, work.
- Analog24 10y ago
putzdown 10y ago
Every time I read about the Anthropic principle I get the feeling I'm missing something. Enthusiasts of the principle seem to be committing a fallacy; perhaps someone can explain why they're not, or why they are. I compare the principle to this. A group of friends get together and decide they'll roll a d20 to decide how to spend the evening. There are various options afoot, but they decide that only if they roll a 20 will they play board games that night. Lo and behold, they roll a 20 and spend the evening playing board games. Later someone says, "How lucky we are to be playing board games!" A skeptic says, "Whatever do you mean by 'lucky'?" Reply: "Well, there was a 1 in 20 chance, and we hit it! That's pretty lucky." The Anthropicist snorts and says, "Hardly! We're not lucky at all. There was a 100% chance. After all, we're playing them." Is that a good analogy? Or does it miss something crucial on one side of the argument or the other?
- colordrops 10y ago
  I get a sense that the idea behind the anthropic principle is that the subjective experience is antecedent to objective reality, perhaps similar to solipsism or panpsychism.
- whack 10y ago
  Here's a better analogy. Joe has OCD. Every morning, he rolls a d100, and if it comes up 1, he hosts a board-game party that night. On day XX/YY/ZZZZ, Joe hosts a board-game party and a bunch of people show up. During the course of the party, Joe reveals to everyone his d100 policy. Tim asks him what his die-roll this morning was. Joe tells Tim that he rolled a 1. Tim exclaims "The only reason we're here is because you rolled a 1! How did this incredible piece of luck come to pass?" Adam responds "There's nothing incredible about what happened. If Joe hadn't rolled a 1 today, we wouldn't be here. We would never have this discussion, or have it on some other day when he does roll a 1."
  - putzdown 10y ago
    Ah, thanks. That's helpful. So would you say that the appeal of the Anthropic principle depends on the multiverse theory (or something similar): the idea that there are an infinite number—or a great many, anyway—of "die rolls", an infinite number of attempts?
RivieraKid 10y ago
Something vaguely related I've been thinking about: When looking at the timeline of life (link below), humans are a completely negligable slice of history. Dinosaurs survived for about 170M years, modern humans have existed for just 200K, civilization for about 10K, and the technological boom has been here for roughly 100 years. Can this be seen as evidence that the timeline of humanity will be relatively short in the big picture? Because it would seem like a strange coincidence to be born at the beginning of it. This is even more true for the survival time of humans with modern technology. Assuming the era of technologically advanced humans will last for, say 200M years, it's extremely unlikely to be born at the first 100 years (0.00005 %). It's interesting to think about how civilization would develop over hundreds, thousands or thousands of thousands years. There have been some pretty significant changes in just the last 100 years, what could happen in millions of years? Civilisation is not a stable system, it seems to be quite volatile. And unlike before, changes and disruptions are not as locally constrained. Perhaps after many thousands of years, there will come a low-probability event that civilization won't recover from. https://en.wikipedia.org/wiki/Template:Life_timeline https://en.wikipedia.org/wiki/Template:Life_timeline
- pavel_lishin 10y ago
  Apparently this is called the Doomsday Argument: https://en.wikipedia.org/wiki/Doomsday_argument https://en.wikipedia.org/wiki/Doomsday_argument
- dwaltrip 10y ago
  I'm having trouble writing out a detailed refutation, but it seems highly speculative to deduce much solely from the notion that "it is very unlikely one would be born in in the first few years of a long technological age". I do think that analyzing the stability and trajectory of civilization is very interesting.
- jodrellblank 10y ago
  It's a nonsensical idea. Imagine you are a soul, in limbo, somewhere outside the universe and elsewhere in another part of reality the universe is progressing through its motions as time goes on. You are an other-reality-style being, yet somehow still allocated as "going to be a homosapiens on Milky Way\Sol\Earth", and your birth will be random during the era of homo sapiens. Now you can argue about the likliehood of where this random birth happens. On the other hand, take away the other place, and the souls, and the spooky assignment of types, and just look at the universe as a thing of matter and energy. Some configuration of matter was born to your parents, from their DNA. It is intimately connected to its surroundings by a continual stream of light, heat, air pressure, physical pressure; over millions of seconds it learns. It learns the patterns of air pressure that correspond to other people talking to it, and it learns what things it can and can't push by trying, and what other people talk about. And it says "isn't it unlikely that I was born here and now, instead of some other time?" And the question makes no sense. _What_ could have been born somewhere else? or somewhen else? Without its parents DNA, without its particular twenty continuous years of sensory input that it learned from, it would not be itself. Some other matter, born to other parents, with other DNA, and other childhood experiences, and other knowledge patterns. It would be someone else. Entirely someone else. And ... that happens, we call it "other people". If you don't believe in a soul, or something like it, what does it mean for you to possibly "be born somewhen else"?
DonaldFisk 10y ago
Why are planetary orbits roughly circular? Is it because (a) if they were any other shape (e.g. very long isosceles triangles) conditions wouldn't be suitable for intelligent life to evolve, and we wouldn't be around to observe it, or (b) Newton's law of gravity constrains them to conic sections. Stable orbit of single planets must be circular or elliptical. Any planets with highly eccentric orbits would have been ejected from the early solar system, leaving only those which are roughly circular? Of course, the answer is (b), i.e. instead of the emergence of intelligent life determining the laws of physics, the laws of physics allow the evolution of intelligent life. But we only agree on that because we already know Newton's law of gravity. If we didn't know it, some people would believe (a) while others would think that one day a law of gravity would be found which determines planetary motion.
- inimino 10y ago
  Why would they be triangular? There is nothing apparently unparsimonious about elliptical orbits, thus there is nothing that requires explaining. The anthropic principle is not about intelligent life determining the laws of physics. There is no magic there. You have the causality backwards.
  - DonaldFisk 10y ago
    No reason. You can decide on any shape you want. I don't have the causality backwards. We don't have a complete knowledge of the laws of physics, and we have something which is unexplained. Whenever this was the case in the past, better laws were found which closed the explanatory gap. Why should it be any different this time?
    - inimino 10y ago
      The point of the anthropic principle isn't to explain it, it's to point out that an explanation is not required. We could find that the laws of our universe are the only possible set of physical laws. This would be the expectation of the Newtonian era. In that case there is nothing to explain. Or it may be, and currently seems likely, that there are many possible sets of physical laws. Then the question of why we happen to have one of the perhaps very few possible sets of physical laws that allows intelligent life to develop seems to require an explanation. The anthropic principle explains why it really doesn't, because in the (possible or actual) universes where intelligent life is impossible, the question simply doesn't come up. The point of the anthropic principle is precisely that we shouldn't expect to close the explanatory gap, because there isn't one. We shouldn't be surprised if physical laws seem to be "tuned" to allow intelligent life to emerge. Imagine that planets orbited in randomly selected geometric shapes, and we happened to be on the only known elliptical one, giving us the conditions required for life. Would this lucky fact require explanation?
hota_mazi 10y ago
Here's another way to look at the Anthropic Principle: https://goo.gl/O6c0Zi https://goo.gl/O6c0Zi

51 points by lainon 10y ago

Not complete without mention of Terry Pratchett: > The UU Professor of Anthropics had developed the Special and Inevitable Anthropic Principle, which was that the entire reason for the existence of the universe was the eventual evolution of the UU Professor of Anthropics. > But this was only a fomal statement of the theory which absolutely everyone, with only some minor details of a `Fill in name here’ nature, secretly believes to be true.

jzl 10y ago
One of my favorite Terry Pratchett quotes is from a typical hilarious character of his pondering the nature of the universe: "Then there was the question of why the sun came out during the day instead of at night when it would be more useful."

posterboy 10y ago

> [is to observe and understand the universe] a lucky break for the intelligent beings that they exist at all? If we were so intelligent, we wouldn't have to ask, so the answer is 42.

edgarvaldes 10y ago

>The Final Anthropic Principle states that once the Universe has brought intelligence into being, it will never die out. How can you propose someting like that? I mean, in a scientific way.

AnimalMuppet 10y ago
You can't. You propose it in a philosophical or mystical way - as completely unfounded speculation, not as science.
deleted 10y ago
[deleted]
vorg 10y ago
The Final Anthropic Principle follows naturally from the Weak/Strong Anthropic Principle. Once intelligence has evolved and observed the Universe with a single first thought, why didn't it then die out? Of course the definition of Intelligence is arguable, anything from a vaguely self-aware rodent to a literature-reading human, and beyond. If we take some person called Ubuntu who discovered how to control fire 130,000 years ago at age 23 years and 7 months in southern Mozambique as having the very first aware thought, then straight afterwards there'd be no more anthropic principle at work causing intelligence to exist in the Universe. The fact we're still here, our small tribe of sole humans not eaten by hyenas or our planet not extinguished by nukes, suggests there could be a Final Anthropic Principle at work.
- yequalsx 10y ago
  I don't understand how this question is relevant: "Once intelligence has evolved and observed the Universe with a single first thought, why didn't it then die out?" What proof, line of reasoning, logical principle, or evidence do you have to believe that a single first thought would lead to anything dying out? What makes you think there is some underlying Anthropic Principle at work in the universe? Saying something could be at work is more or less saying "God did it". It doesn't explain or illuminate anything.
  - vorg 10y ago
    It only takes a single first thought by an intelligence to observe the Universe. Everything occurring up to then (e.g. nucleii, carbon, brains) is highly unlikely and therefore many people suggest an Anthropic Principle to explain it. Once that single first thought by an intelligence has occurred, the Weak or Strong Anthropic Principle is no longer required to explain the existence of intelligence, and so its continuance has the same unlikeliness as other life forms, i.e. ultimate extinction. The fact humans became the opposite of extinct (e.g. fire, scrolls, nukes) suggests that if the Anthropic Principle applies to the emergence of intelligence, something even "stronger" such as the Final Anthropic Principle could apply to the continuance of intelligence. I'm not saying there's an underlying Anthropic Principle in the Universe. I'm answering the question to show that the Final Anthropic Principle is as scientific a proposal as anything else.
DonaldFisk 10y ago
Frank Tipler is the main person proposing this, and he wrote about FAP in The Physics of Immortality: https://www.amazon.com/Physics-Immortality-Modern-Cosmology-Resurrection/dp/0385467990 https://www.amazon.com/Physics-Immortality-Modern-Cosmology-... Here's a review: http://www.fourmilab.ch/documents/tipler.html http://www.fourmilab.ch/documents/tipler.html And here's a quote from it: "it would be possible for each male to be matched not merely with the most beautiful woman in the world . . . but to be matched with the most beautiful woman whose existence is logically possible." verifiable here: http://articles.chicagotribune.com/1994-11-30/features/9411300040_1_frank-j-tipler-omega-point-universe http://articles.chicagotribune.com/1994-11-30/features/94113... I have his previous book, co-written with John Barrow, The Anthropic Cosmological Principle. It's taken more seriously.

elorant 10y ago

That web site seems like it popped-out from 1997.

kardos 10y ago
Last-Modified: Fri, 19 May 2000 20:30:18 GMT Not a bad guess!

AnimalMuppet 10y ago

> The Participatory Anthropic Principle states not only that the Universe had to develop humanity (or some other intelligent, information-gathering life form) but that we are necessary to it’s existence, as it takes an intelligent observer to collapse the Universe’s waves and probabilities from superposition into relatively concrete reality. This is a misunderstanding of what quantum waveform collapse is. It requires an "observation", but not an intelligent observer. For example, in the Schrodinger's Cat thought experiment, the Geiger Counter is a perfectly valid observer.

ewzimm 10y ago
I think you hit on the critical point where this theory goes awry, which is the idea that there is something special about human or animal intelligence which puts it in an entirely different category of other types of information gathering and synthesis. Another option is that the way people gather and synthesize information is just an advanced form of the same processes common to other dynamic systems, localized in layers of biology to create extreme forms of self-referential analysis. It's been a long debate, but the development of artificial intelligence is likely to significantly change the dominant perspective. If we continue to create ever more complex systems that behave intelligently but don't have the same kind of self-awareness as people perceive, we might be able to untangle the concepts of perception, intelligence, creativity, and the sense of self.
ggreer 10y ago
What's the criteria for what counts as an observer? Geiger counters are, but some photon detectors in a delayed choice quantum eraser experiment[1] aren't? 1. https://en.wikipedia.org/wiki/Delayed_choice_quantum_eraser https://en.wikipedia.org/wiki/Delayed_choice_quantum_eraser
- akvadrako 10y ago
  Basically there is no sharp division, but the more the observation spreads, the harder it is to reverse. For one isolated particle, it's easiest. Anything we can reliably read is basically permanent, like a bit flip in a computer. So once a photon is detected, like by making a mark on a screen or camera, it's permanent. In the delayed-choice experiment this happens twice, once for the "interference pattern" and again after the choice. If you accept that, which I think is intuitive, then it makes the DCQE much easier to grasp. If you want to understand the experiment better, I would recommend this thread: https://www.physicsforums.com/threads/who-is-puzzled-by-the-delayed-choice.402497/ https://www.physicsforums.com/threads/who-is-puzzled-by-the-...

AnimalMuppet 10y ago

To state the Weak Anthropic Principle in a form that feels (at least to me) less like philosophical woo: "Universes that cannot be inhabited by intelligent observers are never observed, because there cannot be anyone there to do the observing".

SomeStupidPoint 10y ago
You just stated it as the contrapositive: "NOT Universe can support intelligent life -> NOT Universe can be oberved" ... rather than ... "Universe can be observed -> Universe can support intelligent life (-> Universe has values which can support life)" I'm not sure either is more useful than the other.
- AnimalMuppet 10y ago
  Right. But the way it was stated in the article makes it easy to think of it as the universe requiring rather than the observer requiring. The other versions explicitly get into that kind of nonsense; I wanted to state the weak version in a way that made it clear that it didn't go there. (I suspect that this page states the weak version in that way in order to make the other versions seem more similar.)
  - SomeStupidPoint 10y ago
    Fair point.
  - jwatte 10y ago
    An /observed/ universe requires conditions to cause observers to evolve. I don't but that an "intelligent" observer is needed to collapse the waveform, BTW. That uses a very non-physical interpretation of "observer." Any particle that can absorb information, can be said to be "observing." As simple as a reaction that depends on temperature would do it.
    - deleted 10y ago
      [deleted]

jzl 10y ago

Also relevant: Boltzmann Brains https://en.wikipedia.org/wiki/Boltzmann_brain https://en.wikipedia.org/wiki/Boltzmann_brain A Boltzmann Brain is (very roughly) a "brain", i.e. self-aware entity, that appears spontaneously in the middle of the universe due to random quantum fluctuations. In an infinitely old and infinitely large universe this should actually be a common occurrence. So why are we not Boltzmann Brains ourselves? Why are we all here observing the universe clustered together on this one planet a mere 15 billion years since it came into being? Why is there so much structure?

zardo 10y ago
>Why is there so much structure? Because complex structures (brains) are much more likely to form out of self-assembling sub-structures than from random noise. And Boltzmann brains wouldn't be on hackernews.
acqq 10y ago
> In an infinitely old and infinitely large universe this should actually be a common occurrence. So why are we not Boltzmann Brains ourselves? Our Universe of 13.8 Billion years (think: just 13.8 G years -- my fingernail-sized camera card has more bytes than that number) is infinitely younger than an infinitely old Universe.
- akvadrako 10y ago
  A year is a lot larger than one byte.
- jzl 10y ago
  I didn't word my post very well (I posted the "infinitely old" comment), but what I meant was that it should be more likely to be a Boltzmann Brain in an infinitely old universe than a human standing on Earth in a ~14 Billion year old universe. So why are we the latter rather than the former? That's basically what the anthropic principle is all about. The fact that we are the latter tells us a lot about how the universe, or universes as the case may be, work.
Analog24 10y ago

putzdown 10y ago

Every time I read about the Anthropic principle I get the feeling I'm missing something. Enthusiasts of the principle seem to be committing a fallacy; perhaps someone can explain why they're not, or why they are. I compare the principle to this. A group of friends get together and decide they'll roll a d20 to decide how to spend the evening. There are various options afoot, but they decide that only if they roll a 20 will they play board games that night. Lo and behold, they roll a 20 and spend the evening playing board games. Later someone says, "How lucky we are to be playing board games!" A skeptic says, "Whatever do you mean by 'lucky'?" Reply: "Well, there was a 1 in 20 chance, and we hit it! That's pretty lucky." The Anthropicist snorts and says, "Hardly! We're not lucky at all. There was a 100% chance. After all, we're playing them." Is that a good analogy? Or does it miss something crucial on one side of the argument or the other?

colordrops 10y ago
I get a sense that the idea behind the anthropic principle is that the subjective experience is antecedent to objective reality, perhaps similar to solipsism or panpsychism.
whack 10y ago
Here's a better analogy. Joe has OCD. Every morning, he rolls a d100, and if it comes up 1, he hosts a board-game party that night. On day XX/YY/ZZZZ, Joe hosts a board-game party and a bunch of people show up. During the course of the party, Joe reveals to everyone his d100 policy. Tim asks him what his die-roll this morning was. Joe tells Tim that he rolled a 1. Tim exclaims "The only reason we're here is because you rolled a 1! How did this incredible piece of luck come to pass?" Adam responds "There's nothing incredible about what happened. If Joe hadn't rolled a 1 today, we wouldn't be here. We would never have this discussion, or have it on some other day when he does roll a 1."
- putzdown 10y ago
  Ah, thanks. That's helpful. So would you say that the appeal of the Anthropic principle depends on the multiverse theory (or something similar): the idea that there are an infinite number—or a great many, anyway—of "die rolls", an infinite number of attempts?

RivieraKid 10y ago

Something vaguely related I've been thinking about: When looking at the timeline of life (link below), humans are a completely negligable slice of history. Dinosaurs survived for about 170M years, modern humans have existed for just 200K, civilization for about 10K, and the technological boom has been here for roughly 100 years. Can this be seen as evidence that the timeline of humanity will be relatively short in the big picture? Because it would seem like a strange coincidence to be born at the beginning of it. This is even more true for the survival time of humans with modern technology. Assuming the era of technologically advanced humans will last for, say 200M years, it's extremely unlikely to be born at the first 100 years (0.00005 %). It's interesting to think about how civilization would develop over hundreds, thousands or thousands of thousands years. There have been some pretty significant changes in just the last 100 years, what could happen in millions of years? Civilisation is not a stable system, it seems to be quite volatile. And unlike before, changes and disruptions are not as locally constrained. Perhaps after many thousands of years, there will come a low-probability event that civilization won't recover from. https://en.wikipedia.org/wiki/Template:Life_timeline https://en.wikipedia.org/wiki/Template:Life_timeline

pavel_lishin 10y ago
Apparently this is called the Doomsday Argument: https://en.wikipedia.org/wiki/Doomsday_argument https://en.wikipedia.org/wiki/Doomsday_argument
dwaltrip 10y ago
I'm having trouble writing out a detailed refutation, but it seems highly speculative to deduce much solely from the notion that "it is very unlikely one would be born in in the first few years of a long technological age". I do think that analyzing the stability and trajectory of civilization is very interesting.
jodrellblank 10y ago
It's a nonsensical idea. Imagine you are a soul, in limbo, somewhere outside the universe and elsewhere in another part of reality the universe is progressing through its motions as time goes on. You are an other-reality-style being, yet somehow still allocated as "going to be a homosapiens on Milky Way\Sol\Earth", and your birth will be random during the era of homo sapiens. Now you can argue about the likliehood of where this random birth happens. On the other hand, take away the other place, and the souls, and the spooky assignment of types, and just look at the universe as a thing of matter and energy. Some configuration of matter was born to your parents, from their DNA. It is intimately connected to its surroundings by a continual stream of light, heat, air pressure, physical pressure; over millions of seconds it learns. It learns the patterns of air pressure that correspond to other people talking to it, and it learns what things it can and can't push by trying, and what other people talk about. And it says "isn't it unlikely that I was born here and now, instead of some other time?" And the question makes no sense. _What_ could have been born somewhere else? or somewhen else? Without its parents DNA, without its particular twenty continuous years of sensory input that it learned from, it would not be itself. Some other matter, born to other parents, with other DNA, and other childhood experiences, and other knowledge patterns. It would be someone else. Entirely someone else. And ... that happens, we call it "other people". If you don't believe in a soul, or something like it, what does it mean for you to possibly "be born somewhen else"?

DonaldFisk 10y ago

Why are planetary orbits roughly circular? Is it because (a) if they were any other shape (e.g. very long isosceles triangles) conditions wouldn't be suitable for intelligent life to evolve, and we wouldn't be around to observe it, or (b) Newton's law of gravity constrains them to conic sections. Stable orbit of single planets must be circular or elliptical. Any planets with highly eccentric orbits would have been ejected from the early solar system, leaving only those which are roughly circular? Of course, the answer is (b), i.e. instead of the emergence of intelligent life determining the laws of physics, the laws of physics allow the evolution of intelligent life. But we only agree on that because we already know Newton's law of gravity. If we didn't know it, some people would believe (a) while others would think that one day a law of gravity would be found which determines planetary motion.

inimino 10y ago
Why would they be triangular? There is nothing apparently unparsimonious about elliptical orbits, thus there is nothing that requires explaining. The anthropic principle is not about intelligent life determining the laws of physics. There is no magic there. You have the causality backwards.
- DonaldFisk 10y ago
  No reason. You can decide on any shape you want. I don't have the causality backwards. We don't have a complete knowledge of the laws of physics, and we have something which is unexplained. Whenever this was the case in the past, better laws were found which closed the explanatory gap. Why should it be any different this time?
  - inimino 10y ago
    The point of the anthropic principle isn't to explain it, it's to point out that an explanation is not required. We could find that the laws of our universe are the only possible set of physical laws. This would be the expectation of the Newtonian era. In that case there is nothing to explain. Or it may be, and currently seems likely, that there are many possible sets of physical laws. Then the question of why we happen to have one of the perhaps very few possible sets of physical laws that allows intelligent life to develop seems to require an explanation. The anthropic principle explains why it really doesn't, because in the (possible or actual) universes where intelligent life is impossible, the question simply doesn't come up. The point of the anthropic principle is precisely that we shouldn't expect to close the explanatory gap, because there isn't one. We shouldn't be surprised if physical laws seem to be "tuned" to allow intelligent life to emerge. Imagine that planets orbited in randomly selected geometric shapes, and we happened to be on the only known elliptical one, giving us the conditions required for life. Would this lucky fact require explanation?

hota_mazi 10y ago

Here's another way to look at the Anthropic Principle: https://goo.gl/O6c0Zi https://goo.gl/O6c0Zi