ok, i was in bad mood then, but please read my new post that i posted this evening before this post

i came to a conclusion

And about the colonisation paradox, why should aliens colonise everything that comes to their path?Surely they are not invasive insects without reasoning about what planets should they colonise and what they shouldn't, because without mind you don't have spaceships.My speculation is that even if they decided to colonise most of the lifeless planets of pur galaxy, they are interested in living worlds so much that they don't want to disrupt them by any means, but probe them, maybe experiment a bit, and do not reveal themselves to their observation/test subjects.
And what meaned "colonise" for Fermi?, sending a probe to a world is one thing building entire civilizations on planets is another.

Btw really read my previous post [the long one], I explained my toughts more there.

Or there's even another possibility; that they've colonised Earth in the past and erased all traces to not reveal themselves when they observed that intelligent life is going to bud on Earth.
Civilization building rocket ships capable of 0.1 c or even more should surely conduct their colonisation and subsequent trace erasure quietly using maybe nanobots, picobots, plancktech or some another unknown technology.

I am not claiming any of these hypotheses as fact, they are just possibilities, just and much more probable that that there is noone other than us in a galaxy with around 400 billion stars.

And the notion that there is no civilisation that decided to colonise the whole galaxy is still much more probable than "we are alone"/
What if they developed superior intelligence that told them it's better to improve what you made than needlessly expand and devour?
Or maybe they ended up in a conclusion that fast space expansion would cost more resources than it will bring, be too dangerous and so it's needless to colonise when there's enough resource avilable?Utilitarianism, simple.

Or I have a wild idea that eventually all sapient/transapient beings would be contained in nano pico or plancktech dust dense substrate and so it would be uneeded to go far if you can have trillions of human equivalents in a moon or bigger size superbrain, like the archialect computronium structures in Orion's Arm SCI-FI?

I think that an advanced more than human equivalent intelligence would eventually go for the most efficient and design and resource saving alternative, energy and resorces are limited, remember?

And I also think that even if you had a powerful enough reciever and somehow magically managed to circumvent the laws of nature that forbid for a signal that is weaker than the background noise to be recognisablem, you couldn't make out anything from the Earth's signals because they would be all mixed up due to many channels being on the same frequency.

There are ways to say these things that leave it open. 'IMO' is one. 'I think' is another.

Putting things in statements that imply any kind of definitive conclusion is just asking for reaction. We are talking from a sample of ONE. We don't even know if this ONE sample is typical, strange or unique.

It might be that all those social intelligences out there tell scary stories to their hive-children about beings who have no contact outside their bodies, or it may be that each of the single-being planets tell fairy tales about a planet that supports more than one intelligent being at a time.

Fact is, and it's the ONLY fact we have, we don't know. Everything in this subject is personal opinion or speculation. We should try to avoid any statements that imply 'this is how it really is...' because the one surety is that the Universe will bite the makers of those statements where it hurts the most.

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* Never doubt there is Truth; just doubt that you have it!

Well, I cannot agree more.
My point was that no one can claim "there are no aliens" when we have no data and he's are using faulty logic, and that there are many other explanations that are just as probable, and that the paradox has many solutions, and that it seems to me that there is actually no paradox because it assumes that aliens will behave like humans.

Sorry, I did not mean my previous posts as undeniable facts, just my hypotheses and polemic.

I hope you realize (from the other posts) that there are numerious (not just two) reasons why many of us think ET is (or is not) visiting Earth. There is some doubt about most assumptions we can make. We may be ET, being visited by our cosins. The possibilities are many. That the mainstream science community is in denigal is possible. Neil

You can't assume what aliens may think. Their way of reasoning may be very, um, alien. Somebody may think colonizing the whole galaxy is a superb idea. If the aliens think like we do now, that would be exactly the case. Or, they can indeed just mindless machines or very single-minded. Think Von Neumann machines for example. Machines that can copy themselves.

For him, it meant seeing evidence of aliens here. A group of nuclear scientists at Los Alamos, including Fermi, were discussing about ETs which were a hot topic in 1950. Suddenly, he asked "where are they"? He had figured out the paradox.

By the way, another nuke scientist Leo Szilard provided the first solution: "They are among us, they call themselves Hungarians."

Or they see it as an threat and decide to sterilize the planet before it before the intelligence flowers. Again, one rogue civilization...

Or they give a frak about us. You see, what is intelligence is a very subjective term. They may hardly even really notice us ants. You may have seen an anthill nearby, but that doesn't mean you're then going to be extra-careful not to stomp the insects. You probably have already forgotten the anthill. Yet they're organisms on their own right and unlike any extraterrestrial, our relatives.

How you know that? What you said may as well be just wishful thinking. The problem with my counterclaims is not that they assume a naive civilization, but that these scenarios are possible. If there's been a large number of civilizations before us, the probability of being overrun by another civilization is high if interstellar travel is as easy as it seems (don't say it's hard because we hardly handle orbital spaceflight; for a vastly superior civilization, even interstellar travel may not be a huge problem).

But I personally do hope that you are right.

Energy is basically limitless, and resources are vast if you have the technology advanced enough. How much iron a Mercury-sized planet holds?

__________________
Science is a way of trying not to fool yourself. The first principle is that you must not fool yourself, and you are the easiest person to fool.
-- Richard Feynman

The rarity and the eventual self-imposed and/or ecologically imposed frugality of advanced civilizations may help resolve the Fermi paradox.

Imagine that our civilization manages to work out its current predicaments and enters a new era of rising living standards and shrinking population. It is conceivable that within a couple of hundred years Earth's population may actually be less than its current number. What then? Exploration of space and colonization might be more feasible; however, modest incremental exploration of neighboring planetary systems rather than all out rampant colonization of every Earthlike planet is likely for a civilization that realized that downsizing consumption and taking care of ecosystems is the key to survival. Remember, the Fermi paradox has to be seen in its socioeconomic context-- it was concocted during a period of rapid economic growth and accelerating endless growth seemed like the natural path for our civilization. Now many thinkers are challenging the wisdom of the endless growth and consumption doctrine (for example, in the book "The Upside of Down" and "The Long Emergency") now seems more like a path to disaster. So, it seems likely that a civilization that comes to terms with the limits of growth may do so too late, or, if they realize the limits before catastrophe occurs and downsize as a result, then they are likely to apply this same frugal philosophy to the exploration of the cosmos (it did not work here, why do it out there?). This plus a small number of intelligent beings would help explain away the paradox. But, again, even here Fermi haunts us: all it takes is one galactic civilization that decided to engage in exponential explansion and we should be familiar with those folks by now.

Here are some hypothetical numbers:

Drake equation gives us a total of 10 intelligent planets in the Milky Way galaxy, for the sake of discussion. So, 4e11/10= 4e10 stars don't have an intelaligent planet for a every one that does. Question: How close (I know it must be more than a kilolight year) approximately would the nearest intelligent planet be?

5 of them fail to realize that they must live in harmony with themselves and their ecology and thus fail to achieve interstellar flight or do anything else grand as a result?

Out of the remaining 5, 3 achieve harmony but only explore their solar system and engage in modest colonization (akin to us putting a self-sustaining colony on Mars).

The last two achieve interstellar flight, but are satisfied with colonization of one or two other systems.

Thus, no civilizations engage in rampant exploration, period.

Firstly, there is no way to know the likelihood or otherwise of any correspondence between what we go through on Earth & what others may experience.

And the numbers aren't hypothetical, they're imaginary.
Hypothetically all we currently have to go on is a possible rate for star formation & that the more we look, the more systems with planets we are finding.

Other than that, everything else is just guesswork at best.

It's OK to indulge in possibilities as an act of imagination, but arguing a PoV like this is futile until we know more.

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* Never doubt there is Truth; just doubt that you have it!

What result of the Drake's equation?It can be million or two civilizations, for all what we know.

And for what evidence are you looking?I think that our current or even near future technology is absolutely unable to find any evidence of alien civilizations unless they build some more ineffective Dyson type constructions.Simply,I think as an average human cannot see quasars in the nightsky without big telescopes as we haven't got as good vision as these telescopes but it doesn't mean that they (quasars [aliens]) don't exist.

I totally agree with you.
I just wanna prove to the OP that the paradox is not as paradoxical because we basically don't know anything.
And if intelligent life is so impossible, why do we exist?I don't belive in miracles considering that they shouldn't happen because of the age of the universe.

And about ants and humans argument, it's fallacious because it is assuming that aliens would be as agressive and not caring as us, I think objectively humans are still very primitive and full of animal instinct and the lowest stage of sentience, we have existed just for around 100000 years so we haven't got the time to evolve more.If not for conscience we would be killing each other routinely every day, but whenh I think about developed civilisation, I think of one that is not only developed technically but also morally and intelligently, just imagine that just before 500 years we killed each other just because of religion, imagine how pure being can be if it evolves for billions of years....

Extrapolating our civilisation is bad science because if we had planet destroying weapons and the same degree of agression as we have now it would be the worst nightmare ever and we would last for maybe a year, let alone Dark age civilization with these weapons...

And killing us off as a threat?What can endanger a civilization that can travel all over the galaxy?

Ofc all is just my opinion.

Of course, the search for life in the Universe is still in its infancy. What is hypothetical often times turns out to be imaginary--that is, it is unlikely that reality will comform exactly to our expectations. The numbers I came up with describe one possible scenario. Until we have more data, assigning specific likelihoods to various numbers would be premature. However, I think it is highly unlikely at this point that the original 1960s estimates for the number of galactic civilizations (millions) are correct. Reason: we should have seen some sign that they exist, they would be closely spaced, etc.

I was assuming, again, just for fun, that other civilizations will be roughly like ours in that they will dominate their biosphere in a haphazard before settling into a pattern of sustainable living. Those that don't make this transition, including our current civilization, will face decline and eventual extinction. If the number of civilizations is low to begin with and a good fraction of them succumb to HWM (home-world mismanagement), an even smaller number achieve interstellar flight.

The people above who said that it is bad science to extrapolate from our civilization are the same people who say that the laws of physics and chemistry universality makes the chances of life more likely in the Universe based on extrapolation. This type of position is not contradictory, but a legitimate question is: where is the line in exobiology that separates reasonable extrapolation from unreasonable extrapolation given the universality of natural laws?

We just dont know much.

As for millions of intelligent spieces, depends on what you define as "intelligent" and "civilization", as I have said before, maybe every spiece is so unique that no universally definable definition of civilization exists, for example, would you consider a hive mind that uses technology and order but that is not sapient in level of individual components but sapient as a whole to be intelligent and civilised?

I wasn't saying they're necessarily aggressive. Indeed, as you said aggressiveness is probably a bottleneck for civilizations. Too aggressive, and you self-destruct.

My point was that the aliens don't necessary even realize we're here or don't see us important enough. We think we know what intelligent life or life is and take it granted others think in the same way. A truly alien alien species don't even have to be aggressive, they would simply not notice us. We think a human being is immensely more important than an ant, they may not. That's the ant analogy.

Imagine some sort of silicon-based rock-eaters on Mars that are driven to extinction when earthlings terraform the planet before we even notice they're there, if you will. Another example is Arkady and Boris Strugasky's Roadside Picnic.

We can modify our instincts only by changing ourselves. But first, the most rational way to proceed is to modify our societies. Despite all our technological advances, our culture is not much different from bronze age one despite what we may think.

The greatest threat to our survival is ourselves... A starfaring civilization would be practically immortal. Which leads to the Fermi paradox, and that worries me.

__________________
Science is a way of trying not to fool yourself. The first principle is that you must not fool yourself, and you are the easiest person to fool.
-- Richard Feynman

Well, I have to agree but, anyways, we dont know anything.

I have to respectfully disagree with one thing you have said here. I do not consider SETI to be a "great silence". We've got a galaxy about 13 billion years old, our system is about 4.5 billion years old, and we've been examining the skies (without much consistency, no less) for roughly 40 of those years. That a drop of water in an ocean of time.