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have they found anything?

The logic that says, "I can prove by the lack of evidence that there are no intelligent civilizations that are millions of years in advance of our own in the galaxy" does not prove that there are no other intelligent civilizations besides ourselves in the galaxy. In fact, it doesn't rule out a galaxy full of intelligent civilizations at or near our own technological level.

I think the primary flaw in this argument (aside from assuming that any technology that is possible to attain will be attained, and that any technology that is attained will have been used millions of years ago) is that it moves the goalposts. We're not talking about arguments for or against the existence of super-advanced technological civilizations that have existed for millions of years. I would stick with what we know for sure is possible (ourselves) and ask what it would take to prove that civilizations just like our own do not exist in the galaxy.

We have nowhere near enough information to make any such conclusion.
 
JoeTheJuggler said:
The logic that says, "I can prove by the lack of evidence that there are no intelligent civilizations that are millions of years in advance of our own in the galaxy" does not prove that there are no other intelligent civilizations besides ourselves in the galaxy. In fact, it doesn't rule out a galaxy full of intelligent civilizations at or near our own technological level.

I think the primary flaw in this argument (aside from assuming that any technology that is possible to attain will be attained, and that any technology that is attained will have been used millions of years ago) is that it moves the goalposts. We're not talking about arguments for or against the existence of super-advanced technological civilizations that have existed for millions of years. I would stick with what we know for sure is possible (ourselves) and ask what it would take to prove that civilizations just like our own do not exist in the galaxy.

We have nowhere near enough information to make any such conclusion.
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In answer to Larian. We have had our present technology for a little over a hundred years, yet we have already sent probes that have left our solar system and are at present travelling into interstellar space. What will we do in say, a thousand years?
To Joe, I say this.
Have you actually sat down and looked at the dozens of coincidences that have made animal life possible on this planet?
Why do you think man finds it dificult to adapt to living in the Sahara Desert?
 
amb said:
In answer to Larian. We have had our present technology for a little over a hundred years, yet we have already sent probes that have left our solar system and are at present travelling into interstellar space. What will we do in say, a thousand years?
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But our probes are not ubiquitous in the galaxy. By your argument based on Fermi's Paradox, we don't exist right now.

I repeat: to make anything of the absence of ubiquitous probes from advanced intelligences wrt to the question of whether or not ET intelligences exist in the galaxy requires you to make a number of unreasonable assumptions. I've refuted them thoroughly already. Please drop this line of argument unless you are willing to respond to my numbered points that refute this approach.

To Joe, I say this.
Have you actually sat down and looked at the dozens of coincidences that have made animal life possible on this planet?
Why do you think man finds it dificult to adapt to living in the Sahara Desert?
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You're stilling using a backward approach to evolution that smacks of Creationist arguments. There were absolutely NO "coincidences" that made animal life possible. Life adapted to the conditions, not the other way around.

I suggest you read up on evolutionary biology before you continue this approach.
 
amb said:
In answer to Larian. We have had our present technology for a little over a hundred years, yet we have already sent probes that have left our solar system and are at present travelling into interstellar space. What will we do in say, a thousand years?
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Again, that's just humans. Stop being such a frikkin humanchauvenist. And those probes that have left our solar system, are any of them heading towards any particular star? How long will it take for those probes to reach said star? (HINT: Our species will most likely be extinct by then!) Do we have plans for any other probes that will leave the solar system? Again, we apparently don't exist still.


amb said:
To Joe, I say this.
Have you actually sat down and looked at the dozens of coincidences that have made animal life possible on this planet?
Why do you think man finds it dificult to adapt to living in the Sahara Desert?
Click to expand...

NAME a coincidence. Cite exactly what about it is a concidence. I contend that there is not a singe coincidence at all, and you are again being a fraking humanchauvinist.
 
I could give you any number of coincidences from the book ''Rare Earth, but it appears you guys reject it out of hand anyway, so why bother.

''The Earth is the only world known, so far, to harbor life. There is nowhere else, at least in the near future, [to which] our species could migrate.'' ---Carl Sagan, Pale Blue Dot.
 
amb said:
I could give you any number of coincidences from the book ''Rare Earth, but it appears you guys reject it out of hand anyway, so why bother.

''The Earth is the only world known, so far, to harbor life. There is nowhere else, at least in the near future, [to which] our species could migrate.'' ---Carl Sagan, Pale Blue Dot.
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The source doesn't matter. It's this backward way of looking at evolution that I reject.

Also, I should point out, we've gone over this before.

Do you remember the business about the Texas Sharpshooter fallacy? That's all you're doing.

Also, no one here is saying human life should be well adapted to other places in the galaxy. That makes no sense. Your Carl Sagan quote says nothing about your Rare Earth theory. You're just making a straw man argument. None of us said that homo sapiens is likely to have evolved in other places in the galaxy.

Here's the problem with the Rare Earth argument: you cite a number of things about the Earth and claim that absolutely every last one of them is a requirement for any type of complex or intelligent life. When queried, you point out that there might be a case for some of them being requirements for human life to have developed. Do you understand that "human life" is not the same thing as "any kind of complex or intelligent life"?

And that's leaving aside for a moment that you could as well argue that what led to the evolution of complex and intelligent life forms on Earth was not the fact that it is so stable, but rather instability in environments that kept shaking up ecology (punctuated equilibrium).
 
Example of a "coincidence": when a baby horse is born, his legs are exactly strong enough to stagger to his feet in order to nurse in 1 g of gravity. If the Earth were significantly larger or closer to the sun, or the sun was more massive, and our gravity was more than 1 g--even by a little bit, then the horse couldn't stand up and nurse and survive and pass on its genes.

Coincidence?
 
amb said:
I could give you any number of coincidences from the book ''Rare Earth, but it appears you guys reject it out of hand anyway, so why bother.
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We DON'T reject them out of hand. They are POOR arguments... Your quote only means that it's the only planet we know of, and the only datapoint we have. If you only had a tomato from Kansas, would that somehow represent every fruit on the planet? Would Kansas soil be the ONLY conditions that even that tomato could grow in, never mind the numerous different biospheres throughout earth that have fruit?

Really, the conditions set forth in rare earth are only applicable to ONE datapoint. I suppose it's an accurate title as far as describing the specific planet that homo sapiens evolved on, but it has zero bearing on any other possible planet with intyelligent life.
 
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Isn't the argument about ''Earth Like'' lifeforms? I won't argue that there's not some planet out there with twice the size and gravity of Earth. That the intelligent inhabitants of this world weigh around two tons. In the infinity of space, most things are possible.
Other Earths are even possible, but rare in my humble opinion.
 
amb said:
Isn't the argument about ''Earth Like'' lifeforms?
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What argument? The question of the existence of ETI is NOT about the question of finding a near duplicate of the Earth and a near duplicate of humans.

You're backpedalling now. That's fine, but you should admit it. You've been saying all along that you don't think any kind of complex life other than the Earth is likely possible in the galaxy.

(And yes, I recognize you've used the softer language of "may be" and "likely", but when I ask if you'll also admit that there "may be" dozens or hundreds of intelligent civilizations in the galaxy, you won't say it. That's why I still say you're arguing the stronger position. If you rule out that possibility, then you are actually arguing that something is the case, not that something may be the case.)
 
amb said:
I won't argue that there's not some planet out there with twice the size and gravity of Earth. That the intelligent inhabitants of this world weigh around two tons. In the infinity of space, most things are possible.
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You have been arguing against exactly that. You've repeatedly stated the Rare Earth Theory positions which is that simple life may be common, but complex life and intelligence is vanishingly rare, and that we are probably the only intelligence in the galaxy, and maybe only one of a dozen in the entire universe. The Rare Earth Theory claims that virtually every detail about the Earth is an absolute essential requirement for complex life, and that finding another near duplicate of the Earth is the only way to find complex life. Since that would be be very rare, it would reduce the number of candidates for intelligent life down to just a few, and almost certainly eliminate the possibility of intelligent life elsewhere.

I can cite many times you have said that you think microbial life is common, but complex life is very rare and requires almost every little feature that the Earth (by "coincidence") has.

I'm glad you have changed your position and admit that a planet not exactly like the Earth could have an intelligent species not at all like humans on it.
 
amb said:
some planet out there with twice the size and gravity of Earth. That the intelligent inhabitants of this world weigh around two tons.
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I for one welcome our two ton overlords!






Oh wait, those would be Americans from Mississippi, wouldn't they... :(


And no, the argument has been for ANY "intelligent" life out there. It could be a gian't crab looking thing, or some amorpheous group conciousness of geleatinous goop, or whatever the hell evolution comes up with on some distant panet. We don't know.
 
arthwollipot said:
We have been broadcasting radio signals for over fifty years. In theory, any civilisation within fifty light years could potentially have detected us.
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Potentially, but not reliably. That nasty inverse square law mucks it up. Even the Ariceibo can't detect us from Alpha Centauri.


As posted in #226:

davefoc said:
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
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Why is it that things have to be repeated so often? :p
 
Fermi's Paradox still holds true until otherwise proven.
 
amb said:
Fermi's Paradox still holds true until otherwise proven.
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Wrong.

If you refuse to reply to my numbered points:

http://www.internationalskeptics.com/forums/showthread.php?postid=4412527#post4412527

then you should at least address the Wiki article that also gives a number of explanations for why they're not here:

http://en.wikipedia.org/wiki/Fermi_paradox#Explaining_the_paradox_theoretically

But at the very least, quit pretending that the argument that there are no other intelligent civilizations in our galaxy based on Fermi's Paradox is in any way a valid argument.
 
Ignore this one.

I got confused thinking I was seeing a new post that rehashed an old argument when in fact I was looking at a very old post.
 
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