Seti@home pointless?

[JoeTheJuggler]

Primary a deliberate misrepresentation of a situation/subject, in such a way that they can attack it.

If there has been any misrepresentation of your position, it's your own doing. You said you don't want them to ask something of you. My paraphrase of your statement is that it doesn't bother you that people pursue SETI and take it seriously, it's that you wish they wouldn't ask you to take it seriously.

I don't think that's what you meant (now) because otherwise you would be able to cite an example of SETI personnel asking anything at all of you.

It like seeing someone being deliberately ignorant in front of your eyes and then they say that they are truly contributing to cause x.
Or like seeing a role play gamer taking his role too serious, mixing up reality and fantasy, and then yourself feeling embarrassed to be of the same species.

So it's not so much that you don't mind people pursuing SETI as long as they don't ask something of you. It's more that you do mind that SETI exists. You are bothered by the fact of the existence of people who take SETI seriously.

OK--you're entitled to that opinion. You should be upfront and own up to that opinion instead of pretending you're being magnanimous if they would only leave you alone.

 

[AWPrime]

If there has been any misrepresentation of your position, it's your own doing. You said you don't want them to ask something of you. My paraphrase of your statement is that it doesn't bother you that people pursue SETI and take it seriously, it's that you wish they wouldn't ask you to take it seriously.

I don't think that's what you meant (now) because otherwise you would be able to cite an example of SETI personnel asking anything at all of you.

Joe, I severely question your grasp of the English language. Are you really incapable of understanding that my statement doesn't require the literal asking?

 

[JoeTheJuggler]

Joe, I severely question your grasp of the English language. Are you really incapable of understanding that my statement doesn't require the literal asking?

I assure you, my grasp and use of English is superior to yours.

You're just backpedaling now. You clearly said you don't mind that SETI exists as long as they don't ask you to take it seriously. What you really meant was that the very existence of SETI and people who think it's important or serious really bugs you--the same way RPG enthusiasts bug you when they speak as if their fictional world were real.

It's not that SETI or the RPG enthusiasts are asking YOU to do anything. It's just their existence that you don't like.

Again, that's fine, but you should admit that that's your position. You're not being magnanimous about anything. Your statement suggested that you were being tolerant, but that these people just wouldn't leave you alone.

 

[AWPrime]

You're just backpedaling now. You clearly said you don't mind that SETI exists as long as they don't ask you to take it seriously.

I have, in context its a figure of speech. Here the word ask can also cover the meanings of demand or expect.

What you really meant was that the very existence of SETI and people who think it's important or serious really bugs you--the same way RPG enthusiasts bug you when they speak as if their fictional world were real.

It's not that SETI or the RPG enthusiasts are asking YOU to do anything. It's just their existence that you don't like.

No, its the self-delusion, not the existence that can annoy me.
Also the use of the word existence in this part is a failure at best, as it insinuates that my position would be counter their existence (murder), while its actually counter to their self-delusion. Now, I can't tell if those kinds of mistakes that you have shown are deliberate or just signs of a poor grasp of the language. But please can you review your posts before you submit them?


Self-delusion is annoying to other people. And the fanatical SETI (personnel, contributors, etc) are really deluded in that they think that they actually do something that really helps in the search for intelligent alien life. The only thing they really contributing to is their own self-worth (not that this is a bad thing).
My message is: Nice that you are enjoying that, but don't delude yourself and simply enjoy it as a hobby.


ps. Also the argument of non-zero-chance isn't an argument at all. A lot of things have probabilities that are non-zero.
For example a guy could try to make an Ark in a desert in case of flooding (can happen if an asteroid hits a nearby ocean). We wouldn't take the guy serious, but if it makes the guy happy and he doesn't break any laws, it is a nice hobby for him. Although his delusion would make him a target for discussion and mocking. But we wouldn't end his existence.

 

[Lonewulf]

Uhm, so you're saying that making an Ark to prevent a world flood based out of the bible is equivalent to listening for directed radio waves?

Radio waves that would work the same throughout the universe these aliens would probably inhabit?

That's your stance? Really?

 

[Typicallucas]

I assure you, my grasp and use of English is superior to yours.

Haha what are you going to compare ****s next?

 

[JoeTheJuggler]

I have, in context its a figure of speech. Here the word ask can also cover the meanings of demand or expect.

The only figurative language in this statement is your use of the word "hobby" to describe SETI. Here's what you said:

I don't care what other people hobbies are, as long as they don't ask of me to take them too serious.

When I pressed you about what or how they ask anything at all of you, it turns out that you do care what they believe. It bugs you that, according to you, they are self-deluded, not that they're asking anything of you or doing anything to you at all.

So you've backpedalled on that first part--the "I don't care" part. You really do care what they do and what they think, right? It's not that they're spending any public money or proselytizing or anything like that.

 

[Lonewulf]

Yes yes, but they think there's a chance that an alien civilization might actually exist, and possibly figured out how to use radio waves! THEY MUST BE STOPPED!

 

[JoeTheJuggler]

Yes yes, but they think there's a chance that an alien civilization might actually exist, and possibly figured out how to use radio waves! THEY MUST BE STOPPED!

And it's entirely unreasonable and delusional to look for evidence.

Actually, AWPrime, I think most of us here agree with you more than we disagree. I think most of us agree that we're not likely to come into contact with ETI in any way in the history of our civilization ever. Most of us think this is so just because everything in the galaxy (and the universe at large) is so spread apart in space and time, not because there's anything unique about the Earth.

Still, there are valid arguments for continuing SETI:

It's not publicly funded, so it takes away from no other facet of space exploration. It doesn't even use dedicated time on the Arecibo radio telescope, but just piggybacks on it at whatever part of the sky it's pointing to for other radio astronomy projects.

There could be side benefits (maybe the discovery of a new type of pulsar or other patterned signal, maybe just improved mathematical algorithms for distinguishing a signal from noise).

We don't know. Even though you and I believe it will never score a hit, we could be wrong. The arrogance of claiming we know something even though we really don't know could be a huge loss to science.

As Shadron pointed out, you can't win if you don't play. This is equivalent to getting a bunch of lottery tickets for almost no cost. I scoff at people who play the lottery, but if someone gave me 10 tickets, I would definitely check to see if any of them was a winner. I would be foolish to throw them away without looking simply because the odds of one being a winner are so vanishingly small.

There's really no other program to look for ETI. With our current technology and economic constraints, there isn't much else we can do to look for intelligent life at any distance.

By the way, we talk about SETI as if the only thing it could detect is a signal from another planet. But what if these self-replicating probes by some ancient intelligent civilization were zipping around our galaxy--maybe not ubiquitous, but relatively common? What if they were sending out generic First Contact radio signals? Then all talk about the limitations of a radio signal with regard to the vast distances to other stars really wouldn't matter.

One of my points of criticism about the argument that we are alone based on the Fermi Paradox is that we may have had a near miss--like a probe passed through here a mere 500 years ago. Surely if the probes were broadcasting radio signals, a program like SETI would make our ability to detect such a thing much greater than waiting for one to find us.

 

[AWPrime]

Uhm, so you're saying that making an Ark to prevent a world flood based out of the bible is equivalent to listening for directed radio waves?

Radio waves that would work the same throughout the universe these aliens would probably inhabit?

That's your stance? Really?

Well in the guy in my example might survive a flood (an inland going tsunami). But in both cases, the odds approach zero, but will keep the person occupied and happy.

First there is no reason to assume that aliens would ever send out a directed radio wave. This even becomes worse if you think about this, they would have to target every star system in range for maybe millions of years.
Then we have the range problem, normal signals have a maximum range of a couple a LYs. Now if you want to reach all over this galaxy (not even this universe). You would need an entire star worth of power. This makes it unrealistic and in some ways decadent from the alien side.

One of my points of criticism about the argument that we are alone based on the Fermi Paradox is that we may have had a near miss--like a probe passed through here a mere 500 years ago. Surely if the probes were broadcasting radio signals, a program like SETI would make our ability to detect such a thing much greater than waiting for one to find us.

Nice idea, but is has a flaw. How fast is such a probe going? In 500 years it may already be beyond the detection range. Also such probes would have limited amount of fuel to use to power any high power radio signals.

So you've backpedalled on that first part--the "I don't care" part. You really do care what they do and what they think, right? It's not that they're spending any public money or proselytizing or anything like that.

I don't care what to do. I care what they think and how they promote themselves, there is a distinct difference here.

If it harms nobody then I can't object to what they do. In their mind it might be serious business, however if I find enough flaws then I don't have to give in to their spoken or unspoken request to take them serious.

 

[JoeTheJuggler]

First there is no reason to assume that aliens would ever send out a directed radio wave.

Except for the fact that we have done it. So using our only sample of what an intelligent civilization does, we can indeed assume that a relatively nearby ETI might send out a directed radio signal.

This even becomes worse if you think about this, they would have to target every star system in range for maybe millions of years.
Then we have the range problem, normal signals have a maximum range of a couple a LYs. Now if you want to reach all over this galaxy (not even this universe). You would need an entire star worth of power. This makes it unrealistic and in some ways decadent from the alien side.

You're making an all or nothing argument. It is possible to send out a directed signal without "an entire star worth of power". I know this for sure because we have sent out such signals, and yet we have not used up a "star worth of power".

Nice idea, but is has a flaw. How fast is such a probe going? In 500 years it may already be beyond the detection range. Also such probes would have limited amount of fuel to use to power any high power radio signals.

How do you know? You can't possibly know these things. In Fermi's Paradox, it was assumed that the probes would be ubiquitous. My problem with making a conclusion that there are no ETIs because we haven't run across a probe means that the probes must truly be ubiquitous (like at least one for every planet around every star in the galaxy), and that for a long time to guarantee that one would be here while we were capable of knowing what it was.

On the other hand, I'm not trying to draw the conclusion that no probe means no ETIs, but scanning the sky with a radio telescope could spot a signal from something other than a star.

ETA: BTW, the "500 years" figure is just a number I pulled out of thin air to suggest a near miss. Radio telescopy would nevertheless greatly increase our chances of detecting a near miss. The arguments that show the limited range of SETI's ability to detect a signal don't apply to its ability to detect a signal from a probe or spacecraft.

I care what they think and how they promote themselves, there is a distinct difference here.

Well the thinking part is just a problem for you, I suspect. Because they will continue to think in ways you disapprove of, I'm sure. But what about the way they promote themselves bothers you?

How exactly do they promote themselves? I remember getting a forwarded e-mail about 10 years ago about the SETI@home project that said you could "help find ET". Is that what you mean? If so, do you know that SETI won't ever find evidence of an ETI?

If it harms nobody then I can't object to what they do. In their mind it might be serious business, however if I find enough flaws then I don't have to give in to their spoken or unspoken request to take them serious.

Frankly, I don't think anyone at SETI cares whether or not you take their work seriously. I don't think there is a spoken or unspoken request. (Or is this again your idea of "figurative" language, and you don't really mean to say that they're making an implied request of anything from you?)

 

[AWPrime]

Except for the fact that we have done it. So using our only sample of what an intelligent civilization does, we can indeed assume that a relatively nearby ETI might send out a directed radio signal.

You're making an all or nothing argument. It is possible to send out a directed signal without "an entire star worth of power". I know this for sure because we have sent out such signals, and yet we have not used up a "star worth of power".

There are things that must be done by an Alien if it really wants to advertise its location.
The signals we have sent out so far, don't have the strength. The signal that would to be sent would need to cover a large part of our galaxy and last for a long time to account for evolution and discovery of science.

How do you know? You can't possibly know these things.

No machine is limitless.

In Fermi's Paradox, it was assumed that the probes would be ubiquitous. My problem with making a conclusion that there are no ETIs because we haven't run across a probe means that the probes must truly be ubiquitous (like at least one for every planet around every star in the galaxy), and that for a long time to guarantee that one would be here while we were capable of knowing what it was.

That is because only that would be a serious attempt by any ETI.

On the other hand, I'm not trying to draw the conclusion that no probe means no ETIs, but scanning the sky with a radio telescope could spot a signal from something other than a star.

ETA: BTW, the "500 years" figure is just a number I pulled out of thin air to suggest a near miss. Radio telescopy would nevertheless greatly increase our chances of detecting a near miss. The arguments that show the limited range of SETI's ability to detect a signal don't apply to its ability to detect a signal from a probe or spacecraft.

So? The non-zero argument you seem to love is so extremely weak, that it should be thrown in the trash.

You need to focus on this first step: The aliens are going to make either a real attempt or we will discover them through their casual signals.
The former would mean a massively powerful signal and/or probes everywhere. In the latter they would need to be our next door neighbors.

Then is also the factor is time, the odds of discovering anything increase greatly the more range one has. However the more distance between them, the more difficult communication becomes. As soon as any reply takes more then one lifetime, then people will simply file away the fact of their existence and stop caring. Like going to the moon, in the beginning it was an world event, then reality hit and it was clear that continuing to go to the moon wasn't worth the money.


ps. The most plausible scenario of communication with alien intelligent life is this:
Civilization 'A' looks with its telescopes for systems that might support life. This civilization then sends seed ships to such planets. If successful a branch civilization will form and it will repeat this. Now after 'n' amount of years and branches, a seed ship arrives at a planet with that has native civilization 'B'. A has an oops moment, and what happens afterward is unknown, but likely war in some form.

 

[JoeTheJuggler]

No machine is limitless.

And do you know that a self-replicating machine is impossible?

ETA: Do you know that a space-going vessel or probe must carry its fuel with it?

So? The non-zero argument you seem to love is so extremely weak, that it should be thrown in the trash.

I refuse to throw an argument in the trash that has not been refuted. Now--can you do that?

You need to focus on this first step: The aliens are going to make either a real attempt or we will discover them through their casual signals.
The former would mean a massively powerful signal and/or probes everywhere. In the latter they would need to be our next door neighbors.

You're making the same mistake that the Rare Earthers make when they invoke Fermi's Paradox.

We on Earth are an intelligent civilization that has sent out directed signals. We haven't sent out massively powerful signals or sent out probes that are ubiquitous in the galaxy. Yet we exist.

So your dichotomy is false--an ETI need not either make a "real attempt" by sending out a massively powerful signal (using "a star worth of power") or probes that are ubiquitous in the galaxy or be detectable only by our casual signals (by that I guess you mean the fact that our TV broadcasts are only detectable within our solar system even with a radio telescope much more sensitive than Arecibo).

 

[AWPrime]

And do you know that a self-replicating machine is impossible?
ETA: Do you know that a space-going vessel or probe must carry its fuel with it?

Space is quite empty, there rarely is any place to refuel or replicate. So don't expect any probe to waste energy transmitting while its between systems.
Also I never said anything against self-replicating machines, and you know such feature would make continuously traveling probes, just stupid. A probe can just go to a system, make copies of itself and send some of those copies to other systems to repeat the process. Self-replication makes remaining in a system easy.

I refuse to throw an argument in the trash that has not been refuted. Now--can you do that?

I have refuted it several times, you just chose to be willfully ignorant. There are many things that have a non-zero probability, and just because its above zero doesn't make isn't reason enough to do anything. To be useful one would need a practical approach to have any impact.
Heck the chance that you die in a nuclear explosion is larger then zero, but its not very helpful to stay the rest of your life in a bomb shelter. And building one out of sand stone because you couldn't afford reinforced concrete doesn't help make it a serious solution.

You're making the same mistake that the Rare Earthers make when they invoke Fermi's Paradox.

We on Earth are an intelligent civilization that has sent out directed signals. We haven't sent out massively powerful signals or sent out probes that are ubiquitous in the galaxy. Yet we exist.

And you are blind to the problems. We are intelligent, but we haven't done anything to be really detectable. So you can't assume that an ETI will do what we haven't. And even we know what it takes to make ourselves detectable with the present technology.

So your dichotomy is false--an ETI need not either make a "real attempt" by sending out a massively powerful signal (using "a star worth of power") or probes that are ubiquitous in the galaxy or be detectable only by our casual signals (by that I guess you mean the fact that our TV broadcasts are only detectable within our solar system even with a radio telescope much more sensitive than Arecibo).

Which other scenario is there then? Its a simple yes or no decision.

 

[JoeTheJuggler]

Space is quite empty, there rarely is any place to refuel or replicate. So don't expect any probe to waste energy transmitting while its [sic] between systems.

But you don't know this, do you?

and you know such feature would make continuously traveling probes, just stupid. A probe can just go to a system, make copies of itself and send some of those copies to other systems to repeat the process. Self-replication makes remaining in a system easy.

You sure are quick to say what would be "stupid" wrt to an alien technology.

I have refuted it several times, you just chose to be willfully ignorant. There are many things that have a non-zero probability, and just because its above zero doesn't make isn't reason enough to do anything. To be useful one would need a practical approach to have any impact.
Heck the chance that you die in a nuclear explosion is larger then zero, but its not very helpful to stay the rest of your life in a bomb shelter. And building one out of sand stone because you couldn't afford reinforced concrete doesn't help make it a serious solution.

From a cost/benefit analysis, if the thing costs basically nothing, then any non-zero chance of success is worth the effort. That's why I made the analogy of free lottery tickets. Your reply was that you would throw my argument into the trash. That is not a refutation. It's more akin to replying to your opponent's move in a chess game by upsetting the board scattering all the pieces.

Which other scenario is there then? Its [sic] a simple yes or no decision.

Huhn? I'm supposed to answer "yes" or "no" to the question,"Which other scenario is there then?" (And I already answered that question, but I will do so again.)

You made a false dichotomy. You said an intelligent civilization will either send out a powerful broadcast using basically a "star worth of power" or will do nothing and only be detectable by its own activity. I pointed out that we are an intelligent civilization that has sent out directed signals far short of "a star worth of power". I also linked at least once to the Wiki entry on Active SETI which gives the details of the 5 signals we have sent out directed to 17 stars.

I agree with you that the chances of SETI finding a signal from an ETI are vanishingly small. I just don't know why it bothers you so much that this very low cost program that uses no public funding at all exists. You're upset that people are wasting their time on a fruitless endeavor? So should they instead spend time arguing about it in an on-line forum? Is that more productive somehow?

 

[AWPrime]

But you don't know this, do you?

You sure are quick to say what would be "stupid" wrt to an alien technology.

I do make the assumption that they live in the same universe as we do and that the probes won't be perpetual motion machines. So don't ignore reality whenever it suits you. Traveling probes will miss developing intelligent civilizations (and will eventually break down) and replicating probes would be common within their sphere of influence. So we are not yet within the expanding sphere of probes/aliens just don't care/we are the first ones at this level of development.

From a cost/benefit analysis, if the thing costs basically nothing, then any non-zero chance of success is worth the effort. That's why I made the analogy of free lottery tickets.

But that isn't a real effort. Like building a bunker out of 1meter sandstone. Anyone who takes it too serious should expect a discussion at best and most likely a good mocking.
Just doing anything just because the costs are low and the odds are non-zero isn't an argument to take it serious.

You made a false dichotomy. You said an intelligent civilization will either send out a powerful broadcast using basically a "star worth of power" or will do nothing and only be detectable by its own activity.

They either going to make an effort or they won't. It as simple as that. And any serious attempt will try to stack the odds.

I pointed out that we are an intelligent civilization that has sent out directed signals far short of "a star worth of power". I also linked at least once to the Wiki entry on Active SETI which gives the details of the 5 signals we have sent out directed to 17 stars.

A couple of pings to a handful of stars. That isn't a real attempt, its child's play. It will take a permanent signal to all star systems within practical communication range before I can take active SETI even slightly serious. And that is of course ignoring all the other problems.

 

[Bill Thompson]

What is called Fermi's Paradox is elegant and simple and revealing like many great ideas. The very reason why it is called a Paradox and not an Observation is because people refuse to believe it. They refuse to believe what it says and what it means.

When reality shows us something we do not want to believe, it is human nature to come up with any far-fetched absurdity to make ourselves think the way we want.

We are, in a very real sense, frail beings.

==============================================

And the SETI pings are what would be expected to happen when sampling any huge set of ramdomness. SETI only proves that ramdom things occur randomly.

And so, since microbial life is the ultimate random of unlikely ramdonness, SETI shows, indirectly, that we are probably very lonely beings.

 

[JoeTheJuggler]

I do make the assumption that they live in the same universe as we do and that the probes won't be perpetual motion machines.

Yes, and neither of those assumptions rule out scenarios where SETI could get a hit. The point is, we don't know, so we should look.

But that isn't a real effort. Like building a bunker out of 1meter sandstone. Anyone who takes it too serious should expect a discussion at best and most likely a good mocking.
Just doing anything just because the costs are low and the odds are non-zero isn't an argument to take it serious.

No True Scotsman fallacy.

You clearly said that an intelligent civilization either sends out a signal with "a star worth of power" or does nothing. I pointed out that it's a false dichotomy since we are an intelligent civilization that has done something in between those two extremes.

They either going to make an effort or they won't. It as simple as that.

Unless any effort they make falls short of "a star worth of power" in which case you don't count it as a "true effort".

A couple of pings to a handful of stars. That isn't a real attempt, its child's play.

Is there any reason you assume that another intelligent civilization can't possible do exactly what we have done?

Again, I agree with you that SETI is not likely to get a successful hit. (I think we are unlikely ever in our history to encounter another ETI just because everything is so far apart in space and time.) I disagree with you that it's a pointless project, though.

I've listed my arguments before, and you have not addressed them all (any one of which is sufficient to make SETI worthwhile). I'll number them this time.

1. Even though you and I believe it highly unlikely that SETI would ever detect a signal, we could simply be wrong. The thing about the unknown technology of a unknown intelligent civilization is that it's unknown.

2. SETI is extremely low cost and uses no public funding at all. Therefore any non-zero chance of success is worthwhile. It costs us nothing at all (not even telescope time at Arecibo). It's like a free lottery ticket given to the human race.

3. There could be spin-off benefits. Finding a new type of pulsar, for example. Or developing better algorithms for sorting out a signal from the noise.

4. Even though SETI could only detect a narrowband signal directed at us at stellar distances, we don't know that other scenarios (like probes or spacecraft that send out radio signals) might not result in hits.

5. Similar to the way you do risk assessment (where you multiply the chances of the bad thing happening by a factor reflecting the gravity of the event--which is why even though airplane accidents are many many times rarer than auto accidents, they tend to result in more fatalities per incident, so we spend a lot more time and money keeping the incidence of airplane crashes low), we should multiply that very low odds times a very high factor reflecting how huge a success would be. Than you compare THAT to the cost (for the public, nothing at all).

 

[JoeTheJuggler]

What is called Fermi's Paradox is elegant and simple and revealing like many great ideas. The very reason why it is called a Paradox and not an Observation is because people refuse to believe it. They refuse to believe what it says and what it means.

Since you're repeating these notions without responding to me, I'll repeat my earlier post:


These arguments depend on several assumptions.
--That the technology is attainable
--That whatever technology is possible will necessarily be realized (there are economic and social reasons why it might not)
--That if other ETIs exist they already existed at least ten million years ago.

Earlier, I pointed you to my previous refutation of the argument based on Fermi's Paradox. Apparently, you didn't bother reading it, since you're making the same bad arguments without responding to my refutations.

I'll copy it here. You can reply to them by number if you wish:

I've already explained what's wrong with using Fermi's Paradox (or the absence of probes from advanced ET civilizations) as evidence for the absence of ET intelligence. I'll review it:

1.) The galaxy could be full of civilizations exactly like ours, and we are undetectable to even our own technology not so far from here. At best you're only proving that much more advanced civilizations haven't existed for a long enough time to fill the galaxy with probes.
2.) The argument assumes a technology that is impossible by today's science. I'm not saying I know for sure FTL or near lightspeed transportation will never be achieved, but it's a weak argument that assumes that such a thing is certain.
3.) Even if this tech is possible, the argument assumes that all intelligent civilizations will necessarily achieve everything that is possible. It could be that civilizations don't last long enough to, or it could be that it's economically unfeasible even if they do.
4.) Why do you use the absence of probes as evidence that no other intelligence in the galaxy exists and not that no other intelligence in the entire universe exists? If we're assuming magic technology, then why not assume quick and easy intergalactic transportation?
5.) The probes would have to be absolutely ubiquitous for it to be impossible to have missed one. What if one passed through, checked out the Earth, and went on its way a mere 1 million years ago?

In this case, the absence of evidence is not evidence of absence.

If you raise Fermi's Paradox again, please answer all of these points. Any one of them is sufficient to debunk it as an argument that we no other ETIs exist in the galaxy (much less in the universe).

 

[AWPrime]

Yes, and neither of those assumptions rule out scenarios where SETI could get a hit. The point is, we don't know, so we should look.

Actually it almost completely rules out the radio detection of the probe approach. There are here, or they will come here or even there will never be here.

No True Scotsman fallacy.

You clearly said that an intelligent civilization either sends out a signal with "a star worth of power" or does nothing. I pointed out that it's a false dichotomy since we are an intelligent civilization that has done something in between those two extremes.

What we have done so far just may as well be nothing. Any civilization that really makes an effort will be obvious in its local area.

Unless any effort they make falls short of "a star worth of power" in which case you don't count it as a "true effort".

Any real effort will stack the odds in its favor, it won't fully rely on luck. One just can't assume that a ETI will be listening at that exact time, frequency, direction and with the proper equipment to hear a single ping.

Is there any reason you assume that another intelligent civilization can't possible do exactly what we have done?

Easy, its quite likely that most intelligent civilizations are pre-science as we have been for most of our existence. The signal duration and strength should be long and powerful enough to compensate for this.

1. Even though you and I believe it highly unlikely that SETI would ever detect a signal, we could simply be wrong. The thing about the unknown technology of a unknown intelligent civilization is that it's unknown.

A poor excuse. They don't have radio yet, they have radio or they have something better (unknown). SETI just assumes the second case, a very poor plan. A better SETI plan would assume the first two cases.
A good plan will take all cases into account.

2. SETI is extremely low cost and uses no public funding at all. Therefore any non-zero chance of success is worthwhile. It costs us nothing at all (not even telescope time at Arecibo). It's like a free lottery ticket given to the human race.

So is stargazing using just your eyeballs. But it doesn't make it a real effort.

3. There could be spin-off benefits. Finding a new type of pulsar, for example. Or developing better algorithms for sorting out a signal from the noise.

More likely to come from leading astronomers and other professions.

4. Even though SETI could only detect a narrowband signal directed at us at stellar distances, we don't know that other scenarios (like probes or spacecraft that send out radio signals) might not result in hits.

Won't help. Physics dictate those will have limited amount of power, and if they are in the neighborhood then they will likely make a stop at earth anyway. And if you assume that they aren't limited by power then you can just as well assume that use warp drive.

5. Similar to the way you do risk assessment (where you multiply the chances of the bad thing happening by a factor reflecting the gravity of the event--which is why even though airplane accidents are many many times rarer than auto accidents, they tend to result in more fatalities per incident, so we spend a lot more time and money keeping the incidence of airplane crashes low), we should multiply that very low odds times a very high factor reflecting how huge a success would be. Than you compare THAT to the cost (for the public, nothing at all).

Nope. Now your just being overenthusiastic about any result.