They're Here...

[Borachio]

I don't see how you can state that "life probably arose in a lot more places than that".

On what are you basing this statement?

edit: Gah! Beaten to it.

 

[Manfred Belheim]

But even assuming life is ubiquitous (for which there's no evidence), there are further unknowns such as the probability of our level of intelligence evolving from that life. There seems to be this general assumption that higher intelligence will always happen and that it's some sort of "end goal" of evolution. But most life has got along just fine by just eating stuff and screwing stuff for hundreds of millions of years. You could even argue that high intelligence is a really bad development in terms of long-term survival because it leads to completely messing up the ecosystem and creating a mass extinction event in a very short timescale. So life could be everywhere and there could still be no other lifeforms anywhere in the universe remotely on our mental level.

 

[warpus]

What are you basing this probability on?

Let's say that the probability that life arises on any random planet in the universe is 1/x. In order for this to only happen once, anywhere in the universe, and nowhere else, x is going to pretty much have to precisely equal the number of planets in the universe. You're going to have to get really really really really lucky for it to only happen once. It's incredibly unlikely that these two values are going to randomly equal each other. They could, but the probability of this is very very low. Therefore, it is far more likely that life arises in the universe 0 times or a multiple amount of times. If you pick any specific value (i.e. it arose only once or it arose only twice or it arose only 58158 times), you are picking a tiny point of probability that is unlikely to actually occur. But if you pick a range of possibilities (i.e. 2 times or 3 times or 4 times or anywhere up to infinity), that contains most of the possible values, and since we don't know the initial probability of life occurring anywhere, we have no choice but conclude that the range of 2 - infinity is more likely to be more likely than just one randomly selected value such as 1.

If you've never studied statistics, this will probably not make much sense to you. Let's put it this way. Say you have a die with 1 trillion sides. What are the chances that you roll exactly 575,876,223? And what are the chances that you roll any other number? Obviously a range of values is much more probable than any specific value you select and predict as the next value to come up when you roll the die.

 

[Manfred Belheim]

Let's say that the probability that life arises on any random planet in the universe is 1/x. In order for this to only happen once, anywhere in the universe, and nowhere else, x is going to pretty much have to precisely equal the number of planets in the universe. You're going to have to get really really really really lucky for it to only happen once. It's incredibly unlikely that these two values are going to randomly equal each other. They could, but the probability of this is very very low. Therefore, it is far more likely that life arises in the universe 0 times or a multiple amount of times. If you pick any specific value (i.e. it arose only once or it arose only twice or it arose only 58158 times), you are picking a tiny point of probability that is unlikely to actually occur. But if you pick a range of possibilities (i.e. 2 times or 3 times or 4 times or anywhere up to infinity), that contains most of the possible values, and since we don't know the initial probability of life occurring anywhere, we have no choice but conclude that the range of 2 - infinity is more likely to be more likely than just one randomly selected value such as 1.

If you've never studied statistics, this will probably not make much sense to you. Let's put it this way. Say you have a die with 1 trillion sides. What are the chances that you roll exactly 575,876,223? And what are the chances that you roll any other number? Obviously a range of values is much more probable than any specific value you select and predict as the next value to come up when you roll the die.

Actually the probability could be much, much less than "one over however many planets there are in the universe". We already know that we exist, so we're not trying to calculate the odds that we might exist. The question is "given that we exist, what are the chances that other life exists" and we have no way of deducing it.

Your reasoning would be like playing the lottery one time, winning it on your first attempt, and having no access to any other information about how the lottery works or what anyone else who ever played it won (or even if anyone else ever played it at all). Yes it's incredibly unlikely that that would happen, but it could happen, and you'd only be asking the question after the fact that it already has happened. Following your reasoning you would then deduce that the odds of winning the lottery are really high, at least 50/50 or something, rather than 1 in several million.

So if we could somehow know that we are the only place in the universe where life has evolved, this wouldn't tell you that the odds are in region of 1/x, just that they were not likely to be much bigger than 1/x, but could be a lot, lot, lot less.

 

[warpus]

You're saying that the universe balanced itself on a needle which has balanced itself on a razor which has balanced itself on a chicken, and has resulted in life arising exactly once and not once more.

I simply ask.. why not two times? why not three? why not four? why not five? why not six? why not seven? why not eight? ... why not 858,658? ... why not 581,681,681? ... why not 568,687,688,221?

Picking one specific value here is going to be far less probable than the combination of all the other possibilities. It's a question of a probability of probabilities.

You're saying "why not once?" should be as probable as "why not twice?" since we have no idea how probable it is. I agree! 100%. We have no idea how probable it is, so a range of values is of course going to be more probable than one incredibly specific prediction.

You might as well say "Life occurred exactly 581,658 times, prove to me that it is less probable than all the other values possible". It's exactly the same statement as "Life occurred exactly 1 time, prove to me that it is less probable than all the other values possible"

 

[Manfred Belheim]

So if we could somehow know that we are the only place in the universe where life has evolved, this wouldn't tell you that the odds are in region of 1/x, just that they were not likely to be much bigger than 1/x, but could be a lot, lot, lot less.

I'm going to walk that back a bit as the odds could also be a lot, lot, lot more than 1/x as well.

You're saying that the universe balanced itself on a needle which has balanced itself on a razor which has balanced itself on a chicken, and has resulted in life arising exactly once and not once more.

No I'm not. I'm not saying it is anything. I'm not the one making any sort of positive claim as to how much life is out there. I'm saying it could be "life exists in literally every single planetary system in the universe", "life exists here an literally nowhere else in the universe", or anything inbetween, and we currently have no knowledge that allows us to say anything more than that.

I simply ask.. why not two times? why not three? why not four? why not five? why not six? why not seven? why not eight? ... why not 858,658? ... why not 581,681,681? ... why not 568,687,688,221?

No reason why not. See above.

Picking one specific value here is going to be far less probable than the combination of all the other possibilities. It's a question of a probability of probabilities.

You're saying "why not once?" should be as probable as "why not twice?" since we have no idea how probable it is. I agree! 100%. We have no idea how probable it is, so a range of values is of course going to be more probable than one incredibly specific prediction.

You might as well say "Life occurred exactly 581,658 times, prove to me that it is less probable than all the other values possible". It's exactly the same statement as "Life occurred exactly 1 time, prove to me that it is less probable than all the other values possible"

Yes. I agree with all of that 100%. The only thing I don't agree with is following up all that with "therefore there's probably loads of life out there".

 

[warpus]

I didn't say there's loads of life out there, I just said that chances are there is more life out there than just our own planet here. And given the size of the universe, there's likely plenty of life out there such that yelling "Hey we're here, come visit" out into the universe is a blatantly stupid idea.

We have no idea what's out there, so we should shut the hell up and keep quiet.

 

[Manfred Belheim]

I didn't say there's loads of life out there, I just said that chances are there is more life out there than just our own planet here. And given the size of the universe, there's likely plenty of life out there such that yelling "Hey we're here, come visit" out into the universe is a blatantly stupid idea.

Yeah but these conclusions don't follow from any of that reasoning.

Also... what's the difference between "loads" and "plenty"?

 

[Ryika]

I didn't say there's loads of life out there, I just said that chances are there is more life out there than just our own planet here. And given the size of the universe, there's likely plenty of life out there such that yelling "Hey we're here, come visit" out into the universe is a blatantly stupid idea.

It's stupid in any case. Either we're yelling into a big nothing with nobody to hear us, or we're yelling into a space that might have predators who want to eat us.

 

[Manfred Belheim]

Is it not kind of moot anyway, since we're not actually doing any yelling? SETI is entirely passive and as far as I know there's no other attempts to send out signals going on, other than a couple of records strapped to probes slowly making their way out there.

 

[warpus]

It's not really a "predators who might want to eat us" problem, but more of a "we know what sort of creatures evolution tends to push to the top of a food chain, and we have no idea what sort of priorities or moral codes these beings might have". If we do run into a spacefaring civilization, chances are that they are a lot more advanced than us. They might just steamroll right over us without even viewing us worthy of consideration, much like we build our cities no matter that insect life has already made its home there. So even any aliens who intercept our stupid messages are "nice", it might not even matter.

So I mean, yeah, I don't think that "Alien or Predator" like aliens exist out there and are looking to hunt or exterminate us... that's probably not the problem. And it's also unlikely anyone will ever get our messages.. but why send them? Playing Russian roulette is a stupid idea.

We ought to be a lot more careful and take some steps to mask our presence here instead.

 

[Borachio]

It's stupid in any case. Either we're yelling into a big nothing with nobody to hear us, or we're yelling into a space that might have predators who want to eat us.

There's another possibility of course. That a benign civilization hears us and comes to our aid.

 

[Manfred Belheim]

Or the sock monsters.

 

[Ryika]

There's another possibility of course. That a benign civilization hears us and comes to our aid.

It's very questionable if we'd even "want" that help. Anything they could offer to us would likely either dramatically change the power balance between our Civilizations which might cause utter chaos, or be completely incompitable with out moral code, or might require us to change completely who we are to "ascent", etc. etc.

It's unlikely that there's a non-intrusive way to "help" us in any meaningful way that would not significantly alter the way we are, and thus create a situation that is also very scary for us.

 

[Borachio]

You can use words like "very questionable" and "unlikely".

But again we just don't know, do we?

 

[Ryika]

No, we don't know, but we can make informed guesses, can we not? We do know human nature, we do know our political systems. The variables we don't know are all based on what the aliens have, and how well they are at reading us and at preventing human nature from doing its thing. Do we want to take that risk, if that's the "positive" outcome?

 

[Valka D'Ur]

I am pretty sure most historians would agree with me that if the native americans had a way to signal to the Europeans in the early 1400s that it would have just lead to their destruction a little bit earlier.

The Vikings were here 400 years earlier than that.

could life precede the big bang?

Imagine if the cyclical nature of the universe (big bang-big crunch) is for real, and material (including life) leftover from a prior universe is not destroyed by the big bang, could it 'fertilize' our universe? Maybe even some life form that develops the technology to avoid being 'crunched'.

Not this again.

The alien debate continues to divide people into the same three camps as the religious debate - Theists, Atheists and Agnosticists. Interestingly, it seems that the same kind of people who deny the existence of an all powerful deity in one place, acknowledge the existence of extraterrestrials in the other place, and vice-versa. Of course not all "I want to believers" are atheist and not all theists are "I don't want to believers", but there is a correlation.

In both cases, extraordinary claims require extraordinary evidence.

And I say that as someone who has been a science fiction fan for over 40 years, and the protagonist in my major NaNoWriMo project is a devoted follower of his patron god(s).

Blind believing is fine for fiction, but the real world requires evidence.

 

[Yeekim]

Relevant:

 

[Ryika]

In both cases, extraordinary claims require extraordinary evidence.

And I say that as someone who has been a science fiction fan for over 40 years, and the protagonist in my major NaNoWriMo project is a devoted follower of his patron god(s).

Blind believing is fine for fiction, but the real world requires evidence.

When it comes to aliens, we simply don't know which is the "extraordinary claim", that we are unique in the universe, or that there are other planets that host societies. The universe supports both claims - we exist, so clearly, life is possible and has some likelihood to exist in the right circumstances, but at the same time, we have not yet found any other planet that hosts life (and certainly not Civilizations). So for the moment, both claims cannot be substantiated in any way, and the only proper position is, in my opinion at least, agnosticism. Aliens are a very real possibility, but we don't know whether or not they actually exist.

 

[warpus]

There's another possibility of course. That a benign civilization hears us and comes to our aid.

Yeah it's possible that an advanced alien civilization will hook us all up with playstations and prostitutes and magical high tech ears that work a lot better than our current ears... but...