Where is Everybody? Fifty solutions to the Fermi Paradox, by Stephen Webb

[ManTimeForgot]

Why didn't ET colonize is an excellent question (sure it poses no moral dilemma), but it begs all sorts of questions that we can't possibly know the answers to.

It presumes ET's goals include expansion/colonization.
It presumes ET is interested in planets (ET might be beyond caring about mere planets).
It presumes the solar system and earth have the right type of gravity and size to be considered by ET (perhaps ET likes Gas Giants larger than Jupiter).
It presumes Earth has resources/atmosphere of the type ET is interested in.
It presumes oxygen based life is what ET is interested in cohabitating with.

And I am sure there are other questions that an ET or scientist would come up with that I have just failed to consider.


Dimensions are more complicated than mere direction, but less complicated than alternate universes (though alternate universes is a valid construct to involve). Dimensions as we are talking about is more like a plane of existence. It is a "different level" of reality. The 5th dimension and above are "spacetime overlap." What this means is precisely bupkiss to us "normal" beings. But to a being with multispatial perception or some other sensory faculties way beyond ours it may not.

And it would be hubris on our part (yet again) to assume that all the dimensions or planes or universes we know about or theorize is all there is to reality. The universe of discourse (all that is; reality) for our purposes of discussion has become so large as to be logically indeterminate (we can know nothing about what we talk about, and so all assumptions become equally true and false).


Perhaps you all are correct and ET is rare. Perhaps ET never wants to leave his solar system. Perhaps similar habitable planets to your own is hard to find. Perhaps most cultures completely self-destruct, die by cosmic accident, or clash in inter-solar warfare before they can achieve high-level expansion.

Or perhaps just as likely (I say this because statistically we have no idea how rare anything is since we know nothing about the subject) ET doesn't interact with us for one or all of the various reasons I have postulated before.



The point I am trying to make is that speculating about the indeterminate is foolishness at best. We know nothing about what we speak and so coming to any conclusions is logically incorrect.

MTF

 

[Urlik]

The point I am trying to make is that speculating about the indeterminate is foolishness at best. We know nothing about what we speak and so coming to any conclusions is logically incorrect.

MTF

we know roughly what conditions were required for life to start on Earth but we don't need to know exactly what they are for them to work (as they worked just fine without our help in the first place)
there is a statistical probability that those conditions have been met elsewhere in the Galaxy (even with a probability of 99 in a hundred for, there is still the chance that the single role of the dice comes up as the 1 time in a hundred against)
these 2 factors let us hypothesise that there is a probability that somewhere out there an intelligent life form evolved (although they may have evolved from their equivalent of the reptile instead of their mammal or even insect or they may still live in the oceans and never need to develope tools)

it isn't hubris to think this because we know it can happen as it already has and we are the proof.
it isn't hubris to think that life as we know it would have similar goals to us. all life as we know it has the same basic goal from the humble amaoba right up to us and that is reproduction. this leads to expansion until limited by resources. if they have developed a technology that allows them to increase their resources then they will if they want to be able to continue reproducing and planets happen to be a pretty good source of all the resources for life as we know it to continue to reporduce
it isn't hubris to think that the Earth is the type of planet they'd be looking for as in our initial hypothesis we were working with life that has evolved on a planet similar to Earth and would find the Earth a pretty attractive prospect. life in gas giants, if it is even possible, wouldn't be life as we know it because it would have had to originate from a completely different set of circumstances to those on Earth nearly 4 billion years ago and would have followed a very different evolutionary route.

if we limit the possibilities to what we know are possible, the statistical probabality that there is another intelligent life form out there that followed a similar route to us is worth considering

 

[skeptical]

I tend to agree with most of what Urlik just posted. Life is likely to have formed elsewhere in our galaxy. I have never had a problem with that idea. My problem is the concept that intelligent and civilised life is common. I do not believe that. I think that it must be rare, for reasons I have already mentioned.

MTF lists a number of reasons that ET might not have come our way on a colonising mission. Sure, for any single species of ET, such a reason might be valid. However, no such reason will be valid for a large number of ET species. Maybe ET is not, for example, interested in expansion. Sure. And out of 100 different species of ET, perhaps 10 to 20 fit that category.

However, one of the characteristics of life is the drive to disperse. Evolution creates mechanisms for effective dispersal. Seeds and pollen blow in the wind. Coral and barnacles make larvae that drift on ocean currents before settling far from home. Birds and insects fly. Fish swim. Land animals run.

It is utterly realistic to conclude that alien life must also have some kind of dispersal mechanism, to survive and evolve. Intelligent life is likely to have such a mechanism built into its behaviour. For example : human curiosity and restlessness.

For this reason, I think most ET species will, eventually, travel between the stars, and establish colonies elsewhere. Some would be aggressively expansionist.

If intelligent civilised life is common, some will also be oxygen breathers and extremely interested in Earth as it was any time over the last eon.

 

[Parson]

And so Skeptical has brought us full circle. Where are they anyway?

 

[mosaix]

if we limit the possibilities to what we know are possible, the statistical probabality that there is another intelligent life form out there that followed a similar route to us is worth considering

This is sensible. We know it's happened once. We know (approximately) the conditions under which it happened. Because of the number of stars that exist we know that there is a good chance that that the same conditions have existed many times before and may again.