have they found anything?

[Roboramma]

How could it be technically impossible when it happens naturally? Over the time frames involved the natural velocities of comets and the stars themselves are sufficient for a lot of migration.

This is what happens when I make other people's arguments: I tend to screw them up.

Personally, I think that interstellar travel is quite possible and something that we are likely to partake in at some point in the future.

I guess what I'm suggesting though is that it may be impossible for intelligent lifeforms to send themselves to other stars. But to be honest, when you put it like that I can't really agree with that. So, I will modify my statement:

Interstellar travel may be so difficult to engage in that no technological civilization has engaged in it, regardless of how many there have been to this point in the history of the galaxy.

It may be so difficult that while some civilizations do engage in it, they don't get very far: they travel to one or two other nearby stars, perhaps, and don't go further because they find the rewards aren't worth the effort.

Or it may be that civilizations, once they reach the stage that interstellar travel is possible, simply tend not to be interested in interstellar travel.

Personally the Fermi Paradox does modify my guess as to the probability of ETIs in our galaxy, in such a way that I think it's less likely than I did before I'd heard of the Fermi Paradox. But it certainly doesn't modify it all that much, because there are so many possibilities other than "life is rare" that explain it.

 

[JoeTheJuggler]

Joe, come out of your fantasy comfort world and answer these questions:

http://www.internationalskeptics.com/forums/showpost.php?p=5421767&postcount=1016

Asked and answered months ago on this thread. These are basically the Rare Earth arguments.

And your constant insults don't advance the conversation in any way.

ETA: I derive no comfort from acknowledging that we don't know whether or not there are ETIs throughout our galaxy. My position has consistently been just that: we don't know.

 

[JoeTheJuggler]

Interstellar travel may be so difficult to engage in that no technological civilization has engaged in it, regardless of how many there have been to this point in the history of the galaxy.

It may be so difficult that while some civilizations do engage in it, they don't get very far: they travel to one or two other nearby stars, perhaps, and don't go further because they find the rewards aren't worth the effort.

Or it may be that civilizations, once they reach the stage that interstellar travel is possible, simply tend not to be interested in interstellar travel.

Exactly. Or civilizations don't last long enough to discover everything that is technologically possible. Or they lose interest. Or technologically possible doesn't ever equate with feasible.

Personally the Fermi Paradox does modify my guess as to the probability of ETIs in our galaxy, in such a way that I think it's less likely than I did before I'd heard of the Fermi Paradox. But it certainly doesn't modify it all that much, because there are so many possibilities other than "life is rare" that explain it.

Given the size of the galaxy, and how spread apart things are, it doesn't alter my view (which is simply we don't know) any more than a glance into my backyard supports the idea that dogs that live beyond my house are rare or don't exist.

Even if there were relatively many ETIs in the galaxy, we wouldn't expect anything we've observed (receiving a radio message, for example) to be different than it is (no more than I have any reason to expect to see evidence of a dog when I glance out the back window).

Absence of evidence where you don't expect there to be evidence is not evidence of absence.

 

[Bill Thompson]

Jeezus H Christ. This thread is still alive? Has anything changed?

People will not let go of a faith. Ever.

Science and statistics say that intelligent life is uncommon in the universe and the places where they can exist is getting smaller and smaller the more we learn about the universe. So the SETI apologists are motivated by faith and wishful thinking alone.

Joe will be making posts here for years. He will do this as if doing so will change the facts.

 

[Bill Thompson]

Asked and answered months ago on this thread. These are basically the Rare Earth arguments.

And your constant insults don't advance the conversation in any way.

ETA: I derive no comfort from acknowledging that we don't know whether or not there are ETIs throughout our galaxy. My position has consistently been just that: we don't know.

What insults?!

And have you read Rare Earth? It is a title for a book. Or you just find the concept on its face value absurd and refuse to dig any deeper?

No, you have not answered the questions.

What I think is you take it at face value and, of course, by name "Rare Earth" is a silly idea. So you use the straw man argument to draw a simple character of the idea so you can dismiss it.

There are other stars. There are other planets. Too many to count (and yet not infinate). So on the face of it, it is silly to think we are alone. And those who do are arrogant. Right? Am I getting your thought pattern down pretty accurately here?

You have yet to write a simple proof that Santa does not exist.

You have yet to write a proof for a negative. Case statements are not logical proofs. Proove that something does not exist.

you have yet to answer the 10 questions. Taking a brush stroke and labeling them as rare earth nonsense is not answering the questions.

Answer the questions. They do not have the term "rare earth" in them at all. They have just as much to do with frozen yogurt as rare earth. It is simple science, math, and guess what else. STATISTICS!! Everything, as it turns out, really is a numbers game.

Accusing me of insulting you is a cheap trick to avoid answering my questions.

Also, you contradict yourself! You insist that Santa does not exist because there is a lack of evidence that he exists. And then you insist that there is ETI because "absence of evidence is not evidence of absence".

 

[shadron]

Almost nill.

Seems like a pretty unlikely balancing act to me.

A reoccurring inferno like Venus or a dead dirt ball like Mars I think would be more common. Earth has threaded a proverbial needle by astronomically absurd good luck.

It is not just plate tectonics. It is plate tectonics and them all making big enough volcanoes all at the same time to break the freeze. Otherwise, we would be a snowball planet today. That was winning the lottery in a big way. And I do not think such a thing has happened since. So it is perfect timing as well.

We owe our existance to the fact that there are so many stars. Otherwise, the odds would not be in favor for us to exist.

What can you show to back up your hunch? Perhaps all that was needed was a few very ashy, Plinian volcanoes that spread ash all over the place.

 

[JoeTheJuggler]

What insults?!

Your repeated questions of my credentials when I'm not holding myself out as an authority (my arguments stand on their own and don't rely on my credentials), and your questioning my motivation for participating in this thread.

These things are irrelevant to the discussion.

And have you read Rare Earth? It is a title for a book.

Yes, and read the thread. We have discussed the book at some length.

 

[JoeTheJuggler]

And then you insist that there is ETI because "absence of evidence is not evidence of absence".

This is a complete misrepresentation of my position which I have consistently and frequently stated. My position is that we don't know whether ETIs exist.

And I repeat that in this case, absence of evidence is not evidence of absence.

The assumption that if ETIs exist, then evidence of their existence must be ubiquitous in the galaxy is flawed.

The arguments that every detail about conditions here on Earth are prerequisite to the evolution of complex life is flawed (and typical of the backward thinking of the Fine Tuning argument promoted by Creationists).

 

[amb]

We have had radio/television/ astronomy signals for around 60 years now, that's a radius of 60 light years in which there are dozens of sun like stars to receive these signals, even in their weakened state a highly evolved civilization would be able to pick them up as would we with the giant radio radar discs that exist around the world that are capable of picking up a signal from a pulsar 100 light years away, yet all there is is silence both ways. Could it be that there's no one there to receive or send back any signals? Perhaps, and this is an old argument, there is only microbial life on most of these if any, life bearing rocky planets?

 

[Roboramma]

Amb, this is from page 6, and has been reposted at least once already.

Can you not see how it shows your last post to have very little significance to the thread topic? Did you not already see that before you posted it (given that you were involved in this discussion when it came up again on page 17 or 18?
If you really disagree and think that this post doesn't clear up this issue, can you please explain why?

It is very unlikely that alien civilizations are going to pick up television transmissions according to the table from this site:
http://www.faqs.org/faqs/astronomy/faq/part6/section-12.html

see copy of table in this post:
http://www.internationalskeptics.com/forums/showpost.php?p=3557598&postcount=82

Note the range for UHF television (2.5 AU) and the range for the UHF carrier (0.3 LY). Neither estimate is enough to make it out to the nearest star. They don't list a range for VHF television but FM radio is in the middle of the VHF television band and the estimated range for that is 5.4 AU. Again no where near enough to make it to the first star.

The optimistic ranges for detecting a nearby planet are based on either massively powerful transmitters or highly focused outputs from large transmitters.

The calculations that I made in a previous post suggested that one would need an Arecibo sized antennae with a 250,000 watt transmitter to be able to send a detectable signal to a planet as far away as 150 light years.

This is easily with the capability of earth's technology. The Arecibo antennae has only limited steering capability. I think it is mostly constrained by the direction it is pointing as it rotates with the earth so there are lots of potential targets it couldn't be aimed at. The 250,000 watts could be pulsed so that no where near 250,000 watt of continuous power would be required. But will the powers that be that control enough of earth's resources ever feel like funding a major effort to transmit to unknown alien civilizations?

Post where the calculation was discussed:
http://www.internationalskeptics.com/forums/showpost.php?p=3565450&postcount=94

I think the most likely intentionally produced electro magnetic radiation produced on the earth today that could be detected by an alien civilization would be from radars. These are focused and some of them are very powerful. I notice that the table lists the range of a particular weather radar as .01 light years. That doesn't validate my guess because it lists the range of a UHF carrier as .3 light years but I suspect that other radars would do better. Military radars might do much better.

But even if the ranges of military radars are much greater than what is listed for the weather radar in the table, the ranges are still probably much too small to get much beyond the nearest stars.

In another post I linked to an article discussing the feasibility of a laser transmitter to reach stars. If the powers that be wanted to dedicate some resources to this idea the authors suggest that we might hit a 1000 light years with a currently feasible optical laser. I think that bumps the stars for which a signal might be detected from about a 1000 that lie within 100 light years to about a 100,000 that lie within a 1000 light years.

The article on the possibility of optical SETI:
http://seti.harvard.edu/oseti/tech.pdf

 

[JoeTheJuggler]

We have had radio/television/ astronomy signals for around 60 years now, that's a radius of 60 light years in which there are dozens of sun like stars to receive these signals, even in their weakened state a highly evolved civilization would be able to pick them up

No they couldn't, and this was covered long ago.

ETA: I also recall that I asked if you're going to assume that magic technology MUST exist if any ETIs exist (and since it doesn't, they don't), why not extend your argument and claim that there are no other ETIs in the entire universe? After all, if you presume magic technology MUST happen, then why not some serious magic technology, like instantaneous teleportation or a panopticon (capable of seeing and playing back all events throughout all of space and time)?

There's also no technology that would let an intelligent civilization thousands of light years away detect the first time humans used fire.

 

[JoeTheJuggler]

By the way, another explanation for the lack of evidence of ETIs is the possibility that they don't want us to see evidence of their existence. Again, if you're going to assume every technology that is possible must have been developed and used millions of years ago, then why not allow for something like the ability to keep a relatively primitive civilization in the dark?

 

[amb]

Read the update of this especially.

http://en.wikipedia.org/wiki/Wikipedia:Reference_desk/Archives/Miscellaneous/2009_March_1

 

[amb]

No they couldn't, and this was covered long ago.

ETA: I also recall that I asked if you're going to assume that magic technology MUST exist if any ETIs exist (and since it doesn't, they don't), why not extend your argument and claim that there are no other ETIs in the entire universe? After all, if you presume magic technology MUST happen, then why not some serious magic technology, like instantaneous teleportation or a panopticon (capable of seeing and playing back all events throughout all of space and time)?

There's also no technology that would let an intelligent civilization thousands of light years away detect the first time humans used fire.

That's nonsense. A civilization only one thousand years ahead of us would seem as magic to us. Who knows what future discoveries will bring, what new form of power using the sun itself, what powerful transmitters and receivers, like you keep saying, we at this stage do not know.

That article in Wiki says we may have to revise our estimates of alien lifeforms in the cosmos because of the negative results which are not likely to improve in the foreseeable future.

 

[Roboramma]

That's nonsense. A civilization only one thousand years ahead of us would seem as magic to us. Who knows what future discoveries will bring, what new form of power using the sun itself, what powerful transmitters and receivers, like you keep saying, we at this stage do not know.

That article in Wiki says we may have to revise our estimates of alien lifeforms in the cosmos because of the negative results which are not likely to improve in the foreseeable future.

There is a big difference between their technology seeming like magic and their technology being capable of any magical thing you can imagine.

If, for instance, you encountered some technologically primitive people and found that one of them was suffering from a disease treatable through modern medicine, and treated them, they might then expect that you could bring their dead friends back to life, but regardless of your technology seeming like magic, it still has limits, and you wouldn't be able to help them there.

Similarly, whatever technological advances are possible, and I'm sure there are many that we haven't even conceived of yet, there are also some which simply are not. You seem to be suggesting that you know which is which when you say that they will necessarily be able to detect our (very faint) signals.

As to your previous post, I haven't finished reading the link, but I'll try to get to it.

 

[JoeTheJuggler]

That's nonsense. A civilization only one thousand years ahead of us would seem as magic to us.

How do you know that?

I don't believe that for a minute.

like you keep saying, we at this stage do not know.

Yes, and you keep making assertions as if you do know.

 

[JoeTheJuggler]

There is a big difference between their technology seeming like magic and their technology being capable of any magical thing you can imagine.

Well said.

And on top of that, amb's argument not only depends on any magical thing one can imagine being technologically possible, it depends on the assumption that whatever is possible absolutely will happen.

The argument depends on the assumption that such things as interstellar travel, colonization/exploration of the galaxy are so inevitable that the lack of ubiquitous evidence of this sort of thing leads to the conclusion that ETIs don't exist.

 

[Bill Thompson]

This is a complete misrepresentation of my position which I have consistently and frequently stated. My position is that we don't know whether ETIs exist.

And how is that any different from saying we do not know if Santa exists?

And, besides, aren't you saying YOU don't know if ETI exists? Shouldn't you speak for yourself here?

 

[Roboramma]

And how is that any different from saying we do not know if Santa exists?

And, besides, aren't you saying YOU don't know if ETI exists? Shouldn't you speak for yourself here?

Well, in the general sense of it's saying we don't know something exists, it's the same.

In the specific sense of why he's saying it, it's very different.

Why is it different? Because there is a great deal of evidence that there is no Santa, whereas there is very little evidence that there are no ETIs.

To put that slightly differently: of the two possibilities:
a) there is no santa
b) there is a santa
"a" is the far more parsimonious conclusion.

Of the two possibilities:
a) there are no ETIs
b) there are ETIs
there is some evidence that leads us toward "a", and some that leads toward "b", but neither has any particularly compelling evidence, so the best we can do is to say, "we don't know".

Now, personally, when I examine the evidence, I think that there being some ETIs in the universe, even in our galaxy, is more likely than not, but I don't find that conclusion to be all that solid, and would not be all that surprised if there were none. That is, I think the evidence leans toward "b", but not particularly strongly.
Joe may be more in the middle than me, which I think is an entirely reasonable position. Others look at the evidence and think it leans more toward "a", which I again consider to be quite reasonable. Those, however, who say that "a" is assured are, in my opinion, fooling themselves, and so far have failed to make a strong case.

As to amb, I'm still not sure where he sits, as sometimes he seems to say that "a" is almost certain, whereas other times he says that "b" is true, but the number of ETIs is certainly very small. I have none of that certainty, I wouldn't be surprised if there were a great many ETIs, nor if there were very very few of them.

 

[LarianLeQuella]

We have had radio/television/ astronomy signals for around 60 years now, that's a radius of 60 light years in which there are dozens of sun like stars to receive these signals, even in their weakened state a highly evolved civilization would be able to pick them up as would we with the giant radio radar discs that exist around the world that are capable of picking up a signal from a pulsar 100 light years away, yet all there is is silence both ways.

OH FOR ****'S SAKE, are you deliberately being daft? This has been addressed NUMEROUS times, and Robo just quoted the specific post. Even with an Aericibo array on A. Centaruri, our civilization is UNDETECTABLE. That's only a measly 4 light years away! Pulsars and stars are totally different... *sigh* It's like arguing wiht a creationist, same old tired canards repeated over and over again. I can see why Joe would accuse you of that mentality.

By the way, I used to think that anyone wihtin 60 light years could detect us, but then that nasty inverse square law showed me the folly of that train of thought and I had to re-evaluate it. Why have you not done so in the faceof physics?

 

[LarianLeQuella]

Of the two possibilities:
a) there are no ETIs
b) there are ETIs
there is some evidence that leads us toward "a", and some that leads toward "b", but neither has any particularly compelling evidence, so the best we can do is to say, "we don't know".

Thank you! Exactly what I've been driving at. The thing that is particlarly frustrating is that in order to support position a, a myriad of unfounded assertions are made ("Rare Earth", "evolution only works as observed on earth with earthlike results", and a "60 light year buble" in particular). By making those tyeps of assertions, proposition a is weakened. The don't necessarially strengthen proposition b, but are just plain unfounded.

 

[JoeTheJuggler]

Well, in the general sense of it's saying we don't know something exists, it's the same.

In the specific sense of why he's saying it, it's very different.

Why is it different? Because there is a great deal of evidence that there is no Santa, whereas there is very little evidence that there are no ETIs.

To put that slightly differently: of the two possibilities:
a) there is no santa
b) there is a santa
"a" is the far more parsimonious conclusion.

Of the two possibilities:
a) there are no ETIs
b) there are ETIs
there is some evidence that leads us toward "a", and some that leads toward "b", but neither has any particularly compelling evidence, so the best we can do is to say, "we don't know".

Yup. We know Santa doesn't exist the same way we know phlogiston doesn't exist--through science.
ETA: Actually we can go farther with the Santa hypothesis. If you include the definition of Santa Claus to be the stuff about him visiting all the homes of children who receive Christmas presents and delivering said presents, we can show that that's impossible.

There is no scientific evidence to support the proposition that we know ETIs do not exist. Again, the best analogy is the one I've been making about the existence of dogs outside my house when a quick glance out the window reveals a complete absence of evidence of such dogs.

ETA: It's not that the absence of evidence is never evidence of absence. It's that the absence of evidence where there's no reason to assume it must exist is not absence of evidence, and that is the case here.

 

[Bill Thompson]

Well, in the general sense of it's saying we don't know something exists, it's the same.

In the specific sense of why he's saying it, it's very different.

Why is it different? Because there is a great deal of evidence that there is no Santa, whereas there is very little evidence that there are no ETIs.

To put that slightly differently: of the two possibilities:
a) there is no santa
b) there is a santa
"a" is the far more parsimonious conclusion.

Of the two possibilities:
a) there are no ETIs
b) there are ETIs
there is some evidence that leads us toward "a", and some that leads toward "b", but neither has any particularly compelling evidence, so the best we can do is to say, "we don't know".

Internet forums are where the uninformed get a chance to preach. You have ignored lots of fundamentals. For example, one fundamental you ignore is that no one cares if there is another planet with ETI with life all over it in another galaxy. In fact, Star Wars could be 100% factual. No one cares. No one cares because the distances between galaxies are too far to care.

No one cares if a creature called Santa exists in some place where we have no hope of every seeing or knowing of.

And ALL of the evidence talken completely leads us to think we are alone in the galaxy and the more we learn the more alone we seem and the fewer places for ETL AND ETI to hide get smaller and smaller.

I am discussing on another web forum the fact that the Book of Abraham has been debunked with a Mormon. I show him the facts and he simply cannot see it. It is as if his brain simply cannot see simple logic. His faith blinds him. It is also our faith in ETI that is the reason why Fermi's Observation is called Fermi's Paradox. We simply cannot see it eventhough it is very simple to understand.

Then again, maybe for some people it is not simple to understand. Maybe most people cannot fathom billions of years. I9 billion years is a hell of a long time. If ETI came about commonly in nature, the Milky Way would be 100% colonized. That is all. We came about late in the game. Our sun and planets came from an older exploded stars. There were lots and lots of star systems before then. I have explained this lots of times. Why is it, in person, I can get people to see this but on the interent I am just wasting my time?

Science works like this. If you belive something exists, you have to prove it. It does not work the other way. You do not prove that something does NOT exist. That is impossible.

Let me put it this way. It is highly improbable that there is anyone in the Milky Way like us. In fact, it is a huge waste of money.

A multi-millionare friend of mine, Paul Allen, has build a huge telescope array in California to find a signal form ETI. Paul is not a scientist. He is basically a rich guy with a lot of faith and dreams. I think that he should have thrown that money towards cancer research. Ironically enough, he has gotten cancer.

Before Seti@Home was launched people would spend their retirement money and kids college funds on radio equipment listening for signals. It seems to me that they did this because our culture raises us to believe that is it impossible for us to be alone.

The irony of ironies is that if they was ETI, they would not be interested in us at all because we are so stupid.

 

[Roboramma]

Internet forums are where the uninformed get a chance to preach.

No argument here...

You have ignored lots of fundamentals. For example, one fundamental you ignore is that no one cares if there is another planet with ETI with life all over it in another galaxy. In fact, Star Wars could be 100% factual. No one cares. No one cares because the distances between galaxies are too far to care.

I care. So clearly your assertion that no one cares is false.

There are even ways to look for such civilizations. If you are right and ETI tends to colonize its galaxy we can look for the evidence of their technology in those galaxies. Dyson spheres, etc.

And ALL of the evidence talken completely leads us to think we are alone in the galaxy and the more we learn the more alone we seem and the fewer places for ETL AND ETI to hide get smaller and smaller.

So make this case. So far all you've said is, "you can't talk about ETI because you haven't proven that it exists, and it's not my job to show that it doesn't." If you have evidence that there are no ETIs, present it.

It is also our faith in ETI that is the reason why Fermi's Observation is called Fermi's Paradox. We simply cannot see it eventhough it is very simple to understand.

Wrong. As I said before, it's called Fermi's Paradox because it is the observations of two apparently contradictory things.

Then again, maybe for some people it is not simple to understand. Maybe most people cannot fathom billions of years. I9 billion years is a hell of a long time.

I would go so far as to say that no one understands billions of years.

If ETI came about commonly in nature, the Milky Way would be 100% colonized. That is all.

That is not all, and you have completely ignored all the arguments to the contrary. Rather than simply continue to make this assertion, why don't you address those arguments?

We came about late in the game. Our sun and planets came from an older exploded stars. There were lots and lots of star systems before then. I have explained this lots of times. Why is it, in person, I can get people to see this but on the interent I am just wasting my time?

Because while that's all well and good, none of it shows that ETIs tend to colonize their entire galaxy.

Nor does it show that, for instance, we're not one of three technological civilizations. The choice isn't between "very very many" and, "only one." There could be thousands, but if you think that an argument that shows there aren't thousands shows that there are no others, I think you've failed to examine your own argument.

Science works like this. If you belive something exists, you have to prove it. It does not work the other way. You do not prove that something does NOT exist. That is impossible.

So, if I say that there is at least one animal species that is not yet known to science, I am necessarily wrong, correct?

Let me put it this way. It is highly improbable that there is anyone in the Milky Way like us.

How do you calculate that particular probability?

 

[amb]

How do you calculate that particular probabilty

Because of the many almost miraculous events that lead to the first life forms on Earth.

 

[Roboramma]

Because of the many almost miraculous events that lead to the first life forms on Earth.

Can you show me that math?

 

[JoeTheJuggler]

For example, one fundamental you ignore is that no one cares if there is another planet with ETI with life all over it in another galaxy. In fact, Star Wars could be 100% factual. No one cares. No one cares because the distances between galaxies are too far to care.

I care. I'm very curious about this universe we live in. I want to know more about it.

At any rate, if you're going to redefine ETIs to mean only ETIs we can interact with, I probably agree with your position. (Rhetorically, though, I don't think that redefinition is honest.) See my first post in this thread (from about a year ago) where I said,

It could be that everything is just so freakin' spread out in space and time, and life forms with whom we'd be able to communicate are so (relatively) rare that it's extremely unlikely that two will ever be in near enough proximity in time and space.

And from my second:

And again, "extremely rare" is a relative idea.

Stuff is really spread out. Higher life forms could occur pretty regularly but still be rare enough that no two such planets would be in proximity in space and the life forms at the appropriate levels to communicate close enough in time for there ever to be communication.

I've been arguing against amb's idea that complex life other than our own probably doesn't exist in the galaxy (and at one point he said there are probably no more than a dozen in the entire universe). As I've been saying all along, the evidence we have doesn't warrant such a conclusion. About all we can say is that we don't know.

Further, we have no reason to suspect there's something actually unique about us. The laws of physics, the availability of various elements, the duration of time--all are the same in many other points in the galaxy.

The Carl Sagan quote I provided several times best expresses my position. Here it is again:

I'm often asked the question, "Do you think there is extraterrestrial intelligence?" I give the standard arguments--there are a lot of places out there, and use the word billions, and so on. And then I say it would be astonishing to me if there weren't extraterrestrial intelligence, but of course as yet there is no compelling evidence for it. And then I'm asked, "Yeah, but what do you really think?" I say, "I just told you what I really think." "Yeah, but what's your gut feeling?" But I try not to think with my gut. Really, it's okay to reserve judgement until the evidence is in.

I got this quote from Sagan's introduction to The Outer Edge: Classic Investigations of the Paranormal edited by Joe Nickell.

 

[JoeTheJuggler]

Because of the many almost miraculous events that lead to the first life forms on Earth.

Can you show me that math?

It doesn't matter anyway, because that's a backward way of looking at things. Life evolved to fit conditions, not the other way around. Calculating the odds of everything that had to happen for humans to evolve and then asking (even as a rhetorical question) "Whoa! What are the odds against that?!" is a form of the Texas Sharpshooter fallacy.

And I think it's no accident that when he tries to argue this way, amb ends up using religious words like "miraculous". This backward approach is the same one the Fine Tuning argument uses. (ETA: And I think Fine Tuner is the next in the series of repackaging a theist idea as something sciency: Creationism, Creation Science, Intelligent Design, and now Fine Tuner. Whatever the label, they're talking about a supernatural/religious non-explanation for natural phenomena.)

 

[Bill Thompson]

It is a faith.
Science looks for things before deciding if they are there.
Faith assumes something is there and ignores all science that says it is not there.

 

[Roboramma]

It is a faith.
Science looks for things before deciding if they are there.
Faith assumes something is there and ignores all science that says it is not there.

Your view of science is somewhat naive, but anyway, no one here has "decided they are there". You have decided they are not, the rest of us are uncertain.

 

[amb]

Can you show me that math?

Not to specification but around billions to one. Remembering that science has yet to solve the riddle of life's beginnings.

 

[Roboramma]

Not to specification but around billions to one. Remembering that science has yet to solve the riddle of life's beginnings.

What I'm getting at is that you are giving a rather specific result, but not giving us the details of how you get that result.

Saying, "Well, it's hard for life to come about, because X, Y, Z" doesn't do it: that could lead to billions to one or tens to one, and you haven't distinguished between those two, so how do you expect to convince us to do so?

Basically, so far all the arguments here have been very vague, which isn't surprising given that, once again, the real conclusion is we don't know.

 

[Bill Thompson]

Joe, in this issue, your only barrier to knowledge is the perception that you already have it.

 

[Bill Thompson]

Your view of science is somewhat naive, but anyway, no one here has "decided they are there". You have decided they are not, the rest of us are uncertain.

But to go with what we know so far, it is unlikely and as time goes on it become less likely as we learn more. Experience shows that once something points one way it does not reverse itself.

It is not just a game or a matter of opinion. It is a gamble. Do we gamble our time and resources towards looking or do we spend our money on more immediate and pressing issues -- issues that can save lives?

 

[JoeTheJuggler]

Joe, in this issue, your only barrier to knowledge is the perception that you already have it.

Gee that's quite an insightful and well-reasoned response to the content of the arguments I've made.

Oh wait--no it's not.

ETA: And to repeat for about the umpteenth time: my position is that we don't know. So how is that the perception that I already have knowledge? In fact, your ad hominem remark seems to apply to your position better than it does the one most of us hold--i.e. that we don't know whether or not ETIs exist or if they do how rare or common they are.

 

[JoeTheJuggler]

But to go with what we know so far, it is unlikely and as time goes on it become less likely as we learn more. Experience shows that once something points one way it does not reverse itself.

What?! That's not in the least bit true. It was once thought that the Earth was the center of the universe. It was once thought that humans were separate from the rest of the animal kingdom. The trend, if any, has been the repeated lesson that there is nothing special or unique about humans or that the Earth has any special central location in the cosmos.

It is not just a game or a matter of opinion. It is a gamble. Do we gamble our time and resources towards looking or do we spend our money on more immediate and pressing issues -- issues that can save lives?

We discussed this aspect very early in the thread. SETI is privately funded. It doesn't take money away from anything else.

Also, pretty much any scientific endeavor produces side effects that might benefit us in unrelated areas. (One example I gave is that the SETI@home project probably taught us a lot about distributed information processing. Also, I'm sure the algorithms used to analyze the data from Arecibo have probably improved.)

However, these considerations only apply if you are certain that no ETIs exist, and as has been shown, we have no such certainty. (Again, we've only just barely glanced out the window to get a peek at our own backyard, to use my dog analogy again.)

The Kepler mission, for example, is not a waste of money. There is great value in learning about our universe. If for no other reason but that we humans have curious minds. We ask questions, and remain curious while those questions remain unanswered. And when our questions are answered (provisionally at least), those answers lead us to new questions.

 

[amb]

University of California physicist and astronomer Ben Zuckerman is on record as having said that if the Milky Way were home to technologically advanced civilisations, we would know.

Prof. Zuckerman is no idiot.

 

[JoeTheJuggler]

University of California physicist and astronomer Ben Zuckerman is on record as having said that if the Milky Way were home to technologically advanced civilisations, we would know.

Prof. Zuckerman is no idiot.

You've presented a false dichotomy here. You're suggesting that either Zuckerman is an idiot or his statement is correct. It could be that he is not an idiot and his statement is false.

Also, you're arguing by improper use of authority. The position Zuckerman expressed is by no means the consensus view in the field (see point 4 in the Exposition section here), and it's not based on sound reasoning. (I've argued all the assumptions you'd need to make to think that evidence of ETIs would necessarily be ubiquitous in the galaxy.)

Or maybe you're lifting something out of context and he's talking about a super-advanced technology in a super-long-lived civilization that has motive to spread throughout the galaxy. (And in that case, why not postulate super-advanced technology capable of hiding evidence of their existence from us?)

Zuckerman is involved in the search for extra-solar rocky planets. He's also concerned about environmental issues such as wildlife conservation, deforestation, sprawl, wilderness preservation, overpopulation, energy alternatives, and climate change. (He's also very involved with the Sierra Club.)

He certainly doesn't share the opinion that looking for potential extra solar Earth-like planets that might sustain life is a waste of money.

Did you get that quote from this book?

 

[amb]

No but thanks for that title. I have ordered it. I read that reference from a local newspaper article on SETI. Paul Davies also does not think it's a waste of money, but thinks the odds of finding anything are astronomical. The man who did more for SETI than almost anyone Carl Sagan if he was alive today would be surprised at the results so far, but I'm certain he would lobby the US government to increase the effort.
My only hope is that I'm still alive if ever we get any results. For me, nothing else is as important as finding intelligent life on another world. Alas, I have been born in the wrong era. In around fifty or so years I feel we will know one way or the other whether we are alone in the galaxy or not.

 

[Roboramma]

In around fifty or so years I feel we will know one way or the other whether we are alone in the galaxy or not.

What particular data do you think we'll have in fifty years that will tell us one way or the other?

Personally I think it's possible but extremely unlikely that we'll find out that, yes, there are other civilizations out there in the next fifty years.

We will have some evidence that impacts on the question and can alter our predictions slightly one way or the other: the search for earth like planets will have some interesting data by then, for instance.

But I'm curious what particular data you think we'll find that can give us a definite conclusion.