Glenn Reynolds muses:
Somebody has to be the first intelligent species. If you believe in randomness, why can’t it randomly be us? The odds may be low, but low-probability events happen all the time, and it’s consistent with the available evidence and doesn’t require the invocation of fudge-factors — “cosmic roadblocks” — for which there’s no actual evidence at all.
Glenn correctly argues that low-probability events do occur, all the time. On the other hand, there is low probability, and low probability.
One of my favorite examples in physics is the one about the Second Law of Thermodynamics only being true in the vast majority of cases. Consider a box, with a divider in the middle, hydrogen on one side, helium on the other. Remove the divider, and in a relatively short time the two gases will intermix — as the 2nd Law states, entropy increases. But, wait a really really long time, and you will see entropy reversed — every particle of helium and hydrogen will eventually be found back on its original side, as things stood before the divider was removed. But for even a million or so atoms in such a box, you can calculate the odds (assuming a given temperature and size of box) of such a configuration occurring randomly and get a number of years that is so large it has to be expressed as function of the trillions of zeros in the exponential notation — 1E+trillions, an amount so great the 13 billion years this universe has been around is too infinitesimal to even sensibly compare with such a span.
So, clearly, we should never expect to see such an event happen, right? Right… but. There is actually one situation in which we would expect to observe this phenomenon, and if you read the title of this post you probably know what it is: if your existence as an observer was predicated on such on event, then the odds of you observing the event in your recent past are 1 in 1. Of course, this is a truism, but an important one when we consider the uniqueness of intelligent life, because it helps illustrate the point that no matter how unlikely intelligent life is to arise in time and space, those circumstances had to be met here on Earth in the past few tens of thousands of years in order for us to be here asking why we don’t see more intelligent life out there.
We don’t know how with much precision how unlikely intelligent life is in this Universe as a function of time and space, though we’ve started to map out some of the parameters — only carbon chemistry seems to work, liquid water and an oxygenated atmosphere is probably required, obviously the planet has to be habitable in the sense of not being bombarded with lethal radiation or pummeled by planet-killer asteroids every millennia or two, etc. Some of the other possible requirements are more dubious — does intelligent life need a fast mammal-like metabolism, such as our periodic Ice Ages evolved for us? That seems likely, given the requirements of primate brains, and if a planet must straddle a knife-edge between an eternal Snowball Earth in which life barely exists outside the seas and the seesawing Ice Ages we experienced in order to evolve such a metabolism, that would certainly seem to make intelligent life considerably less likely. Are active plate tectonics necessary to drive such changes? Must the Faint Young Sun be balanced by a fortuitous mix of greenhouse gasses? Does our large satellite figure in somehow? Or are some or all of these irrelevant?
While even the more knowable portions of Drake’s equation (those applying to the gross physical conditions rather than the tendencies of other intelligent life to communicate, colonize, or die out) haven’t filled out much since its inception, over the next half-century we should learn quite a bit more, and I suspect we will be able to say by 2060 or so that the odds of finding intelligent life within the past or future of our light-sphere are vanishingly small, measured in something closer to 1 in 1E+billions than 1 in billions. Consider the box: there are immensely large numbers of configurations that do not meet the original: even the configurations that are off by one atom are millions of times more likely to occur, and one suspects something similar probably obtains for the conditions of intelligent life, given its extraordinary complexity — the antithesis of entropy.
UPDATE: A couple of notes — I think Glenn’s thesis of possible “human specialness” is correct, but mostly I’m trying to better define the question of what “special” means, and arguing the answers will be better known over time as we learn more about biochemistry and exoplanetary astronomy (particularly a greater sample size of the conditions of exoplanets). Abandoning geocentrism and denying anthropocentrism is all very well, but the weak anthropic principle applied in an infinite universe nevertheless argues there is no upper limit to how special we might actually be.
As for the lower limits of “intelligent life,” I would argue that only in the past few tens of thousands of years did humans meet that criteria. For instance, there was a period of time of about half a million years during which humans used hand-axes, but this appears to have been more by instinct than learning, as they did not make any other tools over that time period, and I don’t think that quite qualifies. Let us say “intelligent life” for this exercise will be life capable of understanding the question: are there other forms of intelligent life out there?
Comments
36 responses to “Weak Anthropic Principles”
It’s not the odds of mankind coming into existence that concern me, it is the odds of our continued existence. Heinlein’s “Crazy Years” and Dickson’s “Splintering” have arrived.
We can’t have the only commercials in the entire universe, is the way I look at it.
On this “well, we haven’t seen evidence of other life so we must be it” theory, I’ve always been intrigued by pulsars. How can something with a mass greater than our sun spin so precisely at sometimes hundreds of revolutions per second without flying apart?
Maybe they’re traffic signs, warning signals, and/or locator beacons, GPS on a galactic scale.
🙂
The complexity of life isn’t really the antithesis of entropy as much as it is a system in which entropy is relatively low and is maintained in that state for a period of time. This maintenance of low entropy comes at the “expense” of the surroundings (the rest of the universe), which sees a compensatory increase in entropy as a result (though “compensatory” may not be accurate; the entropy of the unviverse was going to increase in any case).
I like the argument (can’t recall where I heard it) that we don’t detect all sorts of other life out there because the time frame over which a civilization would “emit” signals that we would detect would probably be only a very brief span.
Well, yeah. However, the evolutionists, those who take on the origin of life as opposed to those who only think about speciation and selection and such, have a problem.
To avoid a Creator, they must insist that it had to happen. Given time and certain conditions, it could not not happen.
We do not have a million atoms on this planet. We have an uncountable number, barely within the bounds of estimation, bouncing around with at least Brownian movement for at least a billion years under every imaginable physical condition with a number of encounters impossible to calculate, unless one uses the E factor. Even then, possibly it would be E to the E or something. In addition, in the experiment, helium is an inert gas and would not be snatching on to the next hydrogen atom passing by. While a good example of probability, low probability, it does not picture the situation in which it appears life arose.
Unless evolutionists who think life HAD to happen think there’s a mysterious force keeping it from happening elsewhere, it has to happen elsewhere.
Dave — So are you agreeing or disagreeing with Glenn’s thesis?
It sounds initially like you are going to disagree when you say ‘on the other hand…”:
“Glenn correctly argues that low-probability events do occur, all the time. On the other hand…”
But the rest of your article seems to agree with him that we’re ‘it’. You calculate that there is an almost vanishing probability of anyone else being out there.
I figure, since the Universe is infinitely large, there are an infinite number of planets and therefore, an infinite number of planets with life.
I just finished reading a 3-trilogy series where they explore Fermi’s Paradox, which is that any technological race with space faring capability would colonize the galaxy within a million or two years. This should have happened a billion years or more ago and yet, it hasn’t. We should be seeing alien races all over place.
He has aliens that wipe out any race that gets space travel.
So we have that to look forward to.
The universe can’t be infinitely large, the Big Bang theory precludes it. It is constantly expanding, the idea of expanding infinity is nonsensical.
Anyway, if Dave ends up being correct, perhaps we humans ought to consider broadcasting our cumulative knowledge and wisdom (such as it is) so that future far away civilization might find it. Moreover we ought to be looking for such information from past civilizations. It seems increasingly likely that communication with another civilization will prove impossible, I suppose this is the next best thing.
The term “intelligent life” is an anthropocentric redundancy.
Something has to happen. On Earth it was us. The probability of encountering humans around other stars is indeed vanishingly small. But other life? That’s one to hold in abeyance until we have more data. What about those ?bacteria? in the Martian meteorites? The arguments are probably between those who want desperately to see alien life, and those who want desperately not to see it. Some evidence, no proof.
The odds of no life, I suspect, are small. Given evolution, the odds of complex life on a given planet are reasonable, and of intelligent life small but non-zero.
The Fermi question then becomes: is it suicide, murder, or the vastness of space-time? Or merely the short time we’ve been looking?
The Fermi paradox is best solved by noting that the Universe is an exceedingly hostile place over a long time span. Intelligent races (if extra-terrestrial ones exist) simply don’t live long enough to realize how hostile it is before they are wiped out.
There is strong evidence that twin large scale impact events in the Gulf of Carpentaria in northern Australia were the actual cause of the fall of the Roman Empire and the start of the Dark Ages in 535AD. Even today most scientists deny that there have been any such large impact events in recorded history. Of course they concede that there have been 22 large impacts on Jupiter (any one of which would have been an extinction level event on earth)observed since 1994 – simply because they are forced into doing so.
It is only during the lifetimes of current humans that there has been even the vaguest glimmering of the possibility of realizing how dangerous a place the Universe is for life. Gamma Ray bursts and their cause has only been recently discovered. A nearby – within a few thousand light years – Gamma Ray burst aimed at the earth would finish us. Fifty years ago we didn’t even know that danger existed. Fifty years ago comet and asteroid strikes on the earth were considered impossible and laughed at by the scientific establishment. Fifty years ago we didn’t understand the danger of super volcanoes. The window we have to develop technologies to handle those threats are small – our survival as a species depends on making those developments.
>>Somebody has to be the first intelligent species. If you believe in randomness, why can’t it randomly be us?
First of all, if you accept an evolutionary origin of species, its fair to believe that humans are the current end line of a number of successive prior species that might also fairly be considered “intelligent”.
So depending on your definition of intelligence, not only are humans most likely NOT the first intelligent species in the Universe, we’re probably not even the first intelligent species on THIS planet!
As a relevant side-issues, its pretty “anthrocentric” to define “intelligence” at exactly the level of modern human intelligence. Being devil’s advocate, who is to say that there aren’t other species out there so superior in intelligence to humans that they would consider humans to be non-intelligent? (Look around. . .maybe considering humans “non-intelligent” isn’t a stretch!).
Are tool-using chimpanzees “intelligent”? How about dogs or dolphins? The question matters because if you define down intelligence, the likelihood of it existing outside this planet goes up proportionately.
Taking the original question at full face value, sure its certainly possible that humans are the first (or only) species in the universe with human-level intelligence. But given the presumably infinite nature of space is that really the most likely possibility?
Who can say for sure that a million (or a million – million) other intelligent life forms either currently exist or have existed in the past and are now extinct? Note that whether or not such other life forms exist physically close enough to our planet to “matter” is a whole other issue too. (I’d argue that its highly improbable).
How long does it take for intelligent life to develop? Couple billion years, maybe, give or take a few hundred million, even with good odds? So why should we expect other intelligent civilizations to be so significantly out of step with normal processes of evolution?
We are not in any position to provide detectable evidence of our own intelligent existence to other civilizations. We’ve sent out, what, two capsules with engraved tablets, that have not yet even left our solar system. This stuff takes time.
If it takes about this long for intelligent life to develop, we are too far away from each other for any kind of detection. The nearest possibly habitable candidate is Gleise 581g, at 20+ light years away. Those capsules that we sent are traveling at around 25,000 mph, and will take 550,000 years to get there. How do we know that Gliese 581g hasn’t launched a similar expedition 200,000 years ago?
This is the same approach, about, used by Lecompte Du Nouy in his “Human Destiny” where he writes about the time required by mere chance of the emergence of a simple protein: “the time needed to form, on an average, one such molecule [that is, a highly structured molecule of 2000 atoms, like a simple protein] . . . in a material volume equal to that of our terrestrial globe is about 10^243 . . . years”. My personal conclusion is that life doesn’t emerge per se since the whole thing (cosmos) is alive. I like Aristotle’s thinking on energia, potentiality, entelechy. Pick up a pebble on the beach. The end within that is liberty, truth, beauty, wisdom via life. Like the rose is in the bud. These concomitants of consciousness, their emergence, is the meaning and purpose we seek and are really aspects, facets, of the Divine Creative Spirit who wants nothing but to sleep in existential mass in order to experience waking up to “his” real nature. God descends into matter in order to reemerge a self realized being. See the Star of David. See the story of Christ.
We know that mathematics are consistent throughout the Universe, and that physics is based on math and is also consistent throughout the Universe. We also know that the chemistry, which is based on physics and math is also consistent throughout the Universe. Since the math and the physics and the chemistry are consistent, it seems logical to assume that the biology of the Universe – which is based on the math, physics and chemistry – is also consistent. For example, consistent optics, derived from the physical principles of light interacting with gases and liquids, would lead to similar eyes. Consistent atmospheres with the same gases would lead to similar lungs and gills. The symmetry (left/right) of most physiques optimizes balance and control within a gravitational field, so physical laws point to similar physiological constructs. I think when we do finally encounter other life we (well, not me, you) will be startled at how similar to our own it is. Mother nature is consistent and her laws lead to the same outcome everywhere when applied locally, so it seems logically consistent that biological life will follow suit globally. Except, of course, that the people on all those other planets will all have strange foreheads.
To the ‘but it happened’ arguement, I reply with Ymir. The Earth was formed by Odin after he killed Ymir the Frost Giant, and then wadded up the dead body to make the Earth.
Obviously something happened, but Odin and Ymir is considerably less unlikely than random chance. and yes, that may mean that Odin had to hide his handiwork, but even thats less unlikely (considering how dishonest the Nordic pantheon is in tales.)
I am glad to see that Dave Price has a grasp, unlike many people, of just how mega-huge teh odds are.
“There is strong evidence that twin large scale impact events in the Gulf of Carpentaria in northern Australia were the actual cause of the fall of the Roman Empire and the start of the Dark Ages in 535AD”
Only someone with absolutely zero knowledge of Roman history and its increasing societal dysfunction for the preceding 300 years could make such a claim with a straight face.
Only someone with absolutely zero knowledge of European history for the following 1000 years could claim “the Roman empire” fell, as in point of fact it endured quite nicely based in Constantinople, although suffering progressive degradation from the same causes that collapsed the West much faster.
Who is to say that we aren’t the evidence we’ve been looking for? There is plenty of Sci-fi out there dealing with the idea that we’re the aliens on this planet.
Is it not equally possible that humans evolved somewhere else, developed a highly advanced society, and then seeded the universe with slow moving colony ships? If that were the case, the intervals between periods of contact between our colony ship and the distant home world would be long periods of time. Certainly long enough for us to have forgotten who we are and where we came from, and to attribute those breif, sporadic moments of contact to supernatural, god-like beings rather than our homeworld…
Maybe we’re part of the first expansionary wave, the first step towards creating the highly visible galactic society we’re currently looking for? Maybe we are the evidence of the spread of an intelligent “alien” species in its infant stages?
We know that mathematics are consistent throughout the Universe, and that physics is based on math and is also consistent throughout the Universe. We also know that the chemistry, which is based on physics and math is also consistent throughout the Universe. Since the math and the physics and the chemistry are consistent, it seems logical to assume that the biology of the Universe – which is based on the math, physics and chemistry – is also consistent. For example, consistent optics, derived from the physical principles of light interacting with gases and liquids, would lead to similar eyes. Consistent atmospheres with the same gases would lead to similar lungs and gills. The symmetry (left/right) of most physiques optimizes balance and control within a gravitational field, so physical laws point to similar physiological constructs. I think when we do finally encounter other life we (well, not me, you) will be startled at how similar to our own it is. Mother nature is consistent and her laws lead to the same outcome everywhere when applied locally, so it seems logically consistent that biological life will follow suit globally. Except, of course, that the people on all those other planets will all have strange foreheads.
“Rare Earth” by Peter Ward for reasoned criticism of the Drake equation.
GIGO.
Citing the Second Law as an argument as to the possibility of something being “the antithesis of entropy” is plain wrong: the Second Law only applies to closed systems. A planet around a star is *not* a closed system. Life is by definition *not* a closed system. The only truly closed system in the Universe is… the Universe. We think.
Any of the Anthropic Principle gobbledygook based on this misunderstanding of Entropy is gobbledygook.
Astro — good point, see update.
Crimso — yes, I spent some time thinking about that point as well. Since life uses entropy to build order, it is not of course, strictly speaking, anti-entropic. But the vast majority of entropic processes do not build order. Consider what happens when an asteroid strikes a life-bearing planet — all that life vanishes and order is reduced more than it would have been had life continued. Also, life requires some very static conditions to thrive, atronomically speaking. So I would say life is anti-entropic at some level. Consider again the box. There are some random processes which increase order (increase the tendency of atoms of hydrogen and helium to be separated into the two sides). But the number of random processes which would increase disorder are always vastly greater in number, which is why we don’t see entropy decrease very often.
Mark — a common point of confusion. An infinitely large expanse actually can expand, or shrink for that matter. It just remains infinite while doing either. This is apparently well-established in number theory.
looking — a fair point, see the update for how I dodge that one.
John — you might enjoy Tipler’s Physics of Immortality. I started it recently, fascinating thoughts about how God and Heaven may exist more or less as described in JudeoChristian for reasons that fall out of the physics of the Universe.
Richard — they’re extremely dense. OTOH, one of my favorite notions (probably ruled out already) is that the “dark matter halo” we see around galaxies is actually a large number of Dyson spheres hiding advanced civilizations.
Jim — good points. And we’ve already ruled out so many possibilities, so I suspect we will find over the years that intelligent life has to look and function very much like us.
MST — The distinction doesn’t matter much, as the open systems would still require work to be done outside the system to satsisfy the 2nd Law. One can view the solar system as essentially closed for purposes of considering life anti-entropic.
Thanks all for your interesting comments!
If you simply assume that intelligent races arise less often than the average time required for them to spread across an entire galaxy, (Between 100,000 and 1M years, depending on how fast you can push your starships.) coopting all the niches in which other intelligent races might have arisen, then each galaxy only gets one intelligent race, and that race finds itself alone in the galaxy for it’s entire existence.
So, why is it all that surprising that we’re alone? Our being alone is a precondition for our existing AT ALL. Only by the most wild coincidence would we meet with another race.
– a common point of confusion. An infinitely large expanse actually can expand, or shrink for that matter. It just remains infinite while doing either. This is apparently well-established in number theory.
Yes, but I also think about what’s happening waaaaay over that way (Points).
Maybe a couple googol light centuries that way another “universe” was Big Banged into being yesterday or the same time as ours and is expanding or contracting or just going “boom” righhhhhhhht….. now!
Until we leave our solar system or at least can look at others really, really, really closely, we can’t really put odds on anything.
The only thing we know for sure is that there is life on Earth.
Why would there be only the Big Bang that we have identified?
The discussion here seems about two decades out of date.
Origin of life researchers know full well from their work over that time that life does not arise from the laws of physics or chemistry – in fact, these laws work against “natural” formation of life. Atheist Fred Hoyle estimated the chance formation of a living cell at 10^40000 for a reason – chirality, deterioration by UV, need for peptide bonds, etc.
The claims that “organic” molecules have been formed thus are somewhat misleading – only a couple of amino acids, and sometimes pretty toxic compounds. Most experiments end in tar.
Life and its working against entropy is not “just add water” – it requires highly specified information in a coded language, of the order that Bill Gates admits is more complex than any computer program ever written. It is the origin of this information which cannot be explained by regular chemical processes. This is what Anthony Flew realized, part of his journey to acknowledge the existence of a Designer.
Regarding the lucky coincidences that permit our universe to exist as it does, even atheists such as Martin Rees marvel at the improbability of it all (“Just Six Numbers”, etc.). The fact that he takes refuge in multiverses to explain the one we do have only underscores the desperation to find alternate, non-intelligent-design answers, considering the evidence for such is, well, zero. It also introduces the problem of what this random universe-generating mechanism is.
The response that we are “just lucky” and “so what” is answered by John Leslie’s illustration of a trained firing squad missing their stationary target multiple times. It is not reasonable (or, at least, not intellectually curious) to dismiss it as lucky chance; it is more reasonable to start asking why.
Lastly, while probabilities exist for most any event, one must consider its plausibility. The original phase-space volume for the creation of the universe must have been “selected” to a precision of one part in 10^10^123. As Penrose writes,
“This is an extraordinary figure. One could not possibly even write the number down in full” because there are not enough atoms in our entire universe! Regardless of questions about God’s existence or origin, one who accepts these odds as plausible cannot be said to be functioning reasonably.
One does not have to be a theist to see this. See Anthony Flew’s “There Is A God” or Berlinski’s “The Devil’s Delusion” to see why.
Yes Eric, what happened 500 trillion years ago?
An infinite number of Big Bangs have already happened.
CS — I prefer Tipler’s book, at least what I’ve read of it. What you’re claiming is known as the the strong anthropic principle, which is generally not considered a good logical argument.
Veeshir — that’s certainly true, but if we want to know the odds of us running into any of them in our light-sphere we’ll need to know the relationship of those two infinities — i.e., should we expect to find, on average, 10 civilizations per 13 billion light year sphere at this time, or is the average close to something like 1E-1,000,000 per such expanse?
Brett — an excellent point I haven’t seen before. If the time to intelligent civilization is large compared to the time for such a civ to colonize, then the number of civs that see other civs arise would indeed be proportionately small.
“We know that mathematics are consistent throughout the Universe, and that physics is based on math and is also consistent throughout the Universe.”
BTW, I need to point out that this is simply a faith-based statement. Which I happen to believe is true, but faith nevertheless.
“Something has to happen. On Earth it was us.”
This is not the case – at least, according to our best knowledge from research on abiogenesis. Without intelligent input, not much happens that is interesting as far as life is concerned. The belief that something has to happen is essentially a religious one, based on the belief that life arose naturalistically – against all scientific evidence to the contrary. Not to say it’s untrue, just (still) unproven and undemonstrated.
Nothing wrong with holding benign religious views, of course.
Re: the Drake equations, we now know that at least two dozen parameters are needed for life. Our sun, far from being unremarkable, is one of the 10% that are the right size, so that we are not trapped in a tidal lock or so close that we are exposed to solar flares, for example. Our orbit is unexpectedly circular, affording us mild temperature swings. The moon is now understood as crucial to our existence, as a stabilizing force and giving us essential tides. It is also unusually large for our planet, and coincidentally 400 times closer and 400 times smaller than the sun, affords us almost perfect solar eclipses, and our ability to understand the composition of the sun via the flash spectrum, not to mention confirming Einstein’s prediction that starlight bends around the sun.
Even our location in the right type of galaxy is … ah, really lucky, avoiding the busy and dangerous regions of the Milky Way.
Conservative estimates of the odds of meeting all the parameters are … well, less than the number of expected planets in the universe. Drake’s equations using Sagan’s original estimates were OK-ish for that era of knowledge, but are now known to be seriously wrong.
Just saying.
Looks like most of you are saying something I have believed for a long time. All the probability arguments that have been discovered to date point to the only rational conclusion being Intelligent Design. It seems new arguments are just confirming this. ( Irrational conclusions can still be made which do not include ID ).
Yet ID is rejected. I can only conclude the decision to reject ID is one of emotion and not of intellect.
The fool hath said in his heart, There is no God.
Hi, TallDave,
“Generally not considered a good logical argument” is not a good logical argument. This is pretty much the same argument that was given against h. pylorii, plate tectonics, and surgical handwashing.
Without reference to what it is labeled, the points remain – you don’t have to be a theist to realize that something fishy is going on. As Fred Hoyle said, “A common sense interpretation of the facts suggests that a super intellect has monkeyed with physics, as well as with chemistry and biology, and that there are no blind forces worth speaking about in nature.”
Hoyle and his colleague Chandra Wickramasinghe realized “”The enormous information content of even the simplest living systems… cannot in our view be generated by what are often called ‘natural’ processes… There is no way in which we can expect to avoid the need for information, no way in which we can simply get by with a bigger and better organic soup, as we ourselves hoped might be possible… The correct position we think is… an intelligence, which designed the biochemicals and gave rise to the origin of carbonaceous life…”
They did try to leave an escape hatch of sorts: “the intelligence which assembled the enzymes did not itself contain them … which by no means need be God, however,” but you will see the immediate flaw in this. Hoyle turned to directed panspermia, but this does not answer the problems he raised.
The statistical likelihood of something happening usually says it takes X throws of the die to come up with a particular number. What that means is it takes X throws to be sure of coming up with that particular number.
In reality, there is a possibility that the particular number comes up first time. And that presumes we have a particular number we wish to see. What if, say, one percent of the bazillion numbers will do, instead of one of the bazillion numbers?
As regards intelligence, the types of intelligence–dolphins, for example–are irrelevant. For purposes of this discussion, only one type of intelligence matters; the tool-using, technologically capable intelligence that can build an interstellar craft fast enough that the crew remembers the object of the exercise when it arrives at its destination.
Einstein, telling us that time shrinks–or expands, depending on how you look at it–and that mass increases as C is approached, yielding eventually infinite mass requiring nearly infinite force to close in on C, has required generations of SF writers to posit hyperspace.
However, presume travel approaching C is managed and the crews don’t mind getting a year older while their school chums turn senile over the decades, you might get an expansion of a sphere of influence of…you pick it. Ten light years’ increase in radius every thousand years?
In a hundred thousand years….
When seen in terms of infinity, all statistical possibilities become inevitable.
And there has always been infinity.
CS,
Actually, “generally not considered a strong logical argument” is generally considered a strong logical argument. You may call that circular, but it’s a big circle and nearly all of science sits inside it.
The weak anthropic principle is all that is needed to explain any amount of uncertainty — postulating a Creator, as in the strong anthropic principle, does not follow. If God’s out there, He is not dropping any hints.
Eric — True, but see my note to Veeshir above. The problem with positing infinity is that very little of it has any bearing on us — the only things that can affect us are what’s inside our light cone. So when we speak of probabilities, we might as well ignore infinity, except in the special case of defining the likelihood of our own existence (which is special only because it’s necessary for us to be asking the question).
Good point, Dave. There is no way to know what we cannot know. Which is why infinity is generally irrelevant, but it is also why arguments over the unknown (including religious disagreements) are generally a waste of time.