DemoCoder said:
Druga you are handwaving probability figures around. Neither time nor space are infinite, we have pretty good bounds on the size and age of the universe. You don't know the probabilities involved in life, so it makes no sense to pronounce that small probability * age/size of universe => implies high probability of more than one life event. You could be talking about numbers whos exponents differ by dozens of orders of magnitude.
true, this is why such a statement is not really scientifically acceptable, but just looking at the abuncance of life that has permeated this planet in this solar system of ~4.5 bn years age, it is not such a large stretch to imagine billions earth like systems (one estimate was 30 billions in Milky Way) even in our own galaxy which is estimated at about ~14bn years old, giving us more than double the time for the same process to repeat in similar conditions on another place.
Well of course that numbers are too complex to be even approximated, but given that this planet is teaming with life, even at such places with no sunlight at the bottom of the ocean with an energy source helps me
keep an open mind with regards to the idea of intelligent life elsewhere, even within the galaxy. Or something like
this.
Even infinite time or space doesn't save you.
Why not? Moreso it gives it infinite occurances. Same conditions no matter how unlikely the odds might be, given enough time they will produce same result again and again I think this is a logical argument.
The idea that there is something near, but doesn't want to show itself appears to be based purely on belief. Why is it the most plausible? But what basis do you claim life is more likely to be nearer but hidden, than far outside our light cone? On what basis should it be so clustered together?
Basis? Well on the basis that there is life, that it seems to be abundant on this planet, that some scientists even hoped for other primitive lifeforms even in the rest of the really hostile solar system, let alone on billions of earth like planets in our galaxy or possibliy infinite number in the whole universe.
This is where I think the frustration comes in, because alot of implicit and non-supported (faith-based) arguments get thrown around.
Either you have a rational argument for why it is true, or you have evidence, but you "gut feeling" is not sufficient.
Implicit arguments? Well abundance of life here is followed by the ?implausible? conclusion that there might be likely abundance of life under similar conditions elsewhere, even given 30 billion attempts and twice the time in our own galaxy.
The conclusion being implausible only because the other presumably more advance life forms did not either settle here already in friendly environment, or did not come to greet us and tell us "hello, let us teach you how you need to live your life better"?
Chalnoth said:
No, that's not what I mean. I mean that if we take planet X, upon which some intelligent species could someday evolve if left alone, the colonization of planet X by some other intelligent species Y will alter the evolution on planet X so that a new intelligent species cannot evolve.
With all of our advancement, we have not yet stopped wanting to spread ourselves and our culture. My claim is that this desire is a fundamental aspect of life, and something that isn't going to go away. Therefore, any sufficiently-advanced society is going to eventually colonize, if it doesn't kill itself off first.
well with this one we go into more sociological argument, of what the "advanced society" is like, is it more like ours today or "different".
Well my argument for "different" is twofold. Firstly comparing our todays society with the one 8 thousand years ago, it is undoubtebly more refined, more caring overall (like the tsunami response, beginnings of environmental awareness etc). While for prehistory 8k years ago one could argue that it was very evolutionary, ie fittests survives, kills the weaker, etc... Going forward you have more social awarenes together with progress... for example we today do not enjoy gladiatiors in arena killing each other like in relatively developed Roman times, instead we watch football. I think a good argument could be constructed that more developed society is more "integrated" it becomes into the environment and less predatory it is. Thus it is fair to assume that with ups and downs it will go towards integration and not colonization as it was in the past.
The second argument is that a "predatory" society will periodically produce individuals such as Hitler who will not have the moral responsibility towards anyone and will use all the power in their hands to do as they see fit resulting in destruction. More technologically advances such society is more likely is that such a person is fatal for the whole civilization. Thus after a few cycles the civilization either self destructs or becomes integrated with one another and the environment, at the core. Think about it like the "fittests survives" but in this case the fittest civilization is the one who does not spawn "self-destruction ready" individual, as techologically all advanced civilizations will be capable of self desctruction quite easily. Even today we have multiple choices to execute it, either nuclear or biological. Assuming that such a catastrophe happens - imagine a Hitler in 100 years executing viral warfare, and the civilization is decimated but survives it is bound to profoundly affect the remaining individuals and push it into a different direction. IF one cycle is not enough I am pretty certain that it will be either one or another. Even looking around our earths cultures the more peacefull ones to this point were not served by their unwilligness to be good warriors as it was necessary to succed, but in the future this different trait will be essential for survival, as the battle for resources might not be the most important one in our future. - for example - harvesting fusion, with enough efficiency together with nanoengineering might eliminate this problem.
Sure, but as I've said previously, it's much easier to make use of an already-habitable biosphere than worry about artificially creating one (except for the possible exception of planets within the same solar system). It will take a lot of time and natural resources to terraform a planet, and much more in the way of resources to generate a biosphere from scratch.
Well, I claim only ones in our galaxy. That doesn't mean there aren't others in other galaxies, so far that they could never have reached us.
But option #3 makes no sense except in the obscenely-unlikely scenario where the intelligent species is within about 50-100 light years. Only in being that close could they have possibly detected our existence as an intelligent species. And they would also have had to evolve intelligence at almost the exact same time as us for them to not already be here.
Sure. Just bear in mind that the observable universe is finite. The universe with which we have a chance of ever interacting is actually smaller (due to the accelerated expansion), and the universe with which we ever have a practical chance of physically meeting extraterrestrials is even smaller.
following on the arguments above...
on #1 in this last quote - I assume that the technologically advanced civilization, and we speak here about millions of years past us, such problems will be trivial, like forexample flying is trivial for us today while it was impossible even for relatively advanced (comparing with their predecessors) ancient Greeks.
on #2... if universe physics allow FTL, or even some more exotic eventualities like space bending, dimensional travel etc... than whole universe comes into the equation
on #3 ... I think this one follows your "if they could be here they already would be" logic, with which I disagree
on #4 ... I agree that the observable universe is finite, but if the conditions permitting life development are infinite, and FTL, other more exotic ideas are permittable in this universe than even that will not be a problem.
--- I will come back to the others later as I am going to the cinema now