Grifman wrote:I don't believe anywhere I discussed probabilities. I merely said that there are many more factors required by life than mere liquid water. That said, the more factors something requires, the more rare it will be compared using only one of those factors.
See? You are
Grifman wrote:Actually we have no reason or evidence that there is anything more than this composition since life as we know it is all we have evidence for. I think the burden of proof is on you for this one.
Just once, would it be possible to just have a friggin' conversation around here without pretending that we are debating at the Royal Academy of Science using the Queen's Rules? Holy Underpants.
There is no burden of proof on me because I am not making a positive assertion. I'm not telling you that there are other compositions of life. I'm saying that you (or rather the side that you are representing here) hasn't met the burden of proof that this is the only possible composition of life. We don't know because we are far too ignorant as to what is going on out there in the universe. And if "all we have evidence for" is good enough, then clearly *all* solar systems have a rocky planet in the habitable zone that sustains an "advanced" civilization, since right now, 100% of solar systems that we have detailed information about have them. Right?
Grifman wrote:You're assuming your sample size (the universe) is large enough to outweigh the improbabilities. But the problem is you don't know that.
I know that in the context of the statement that I actually made (with the disclaimer that you removed). As long as the probability of hosting advanced life is greater than 1 in 10,000,000,000,000,000,000,000 then advanced civilizations are abundant in the universe.
Grifman wrote:Indeed, you're merely assuming what you need to prove.
No, as I provided the necessary qualifier to my probability calculations.
You can make anything appear likely if you stack the odds in your favor
Kraken used a 1 in 2 chance to stack the odds in his favor. Presuming a probability of 1 in 10,000,000,000,000,000,000,000 is not stacking the deck in my favor. A 1 in 10 sextilliion chance is several orders of magnitude more remote than other estimates I've seen (which are in the trillion scale).
Grifman wrote:Until you establish the likelihood of life developing more than once, you've only got one side of your analysis.
Again, all I said was "*IF* the chance of advanced civilization developing around a star is 1 in 10 sextillion, there are enough stars in the sample set such that there are a hella lot of advanced civilizations (according to the probabilities). And I even simplified it down for you. If you flipped a coin 200 times, you'd probably end up with a lot of heads. That's the kind of frequency we are talking about - *IF* the probability of an advanced civilization developing around a star is as remote as 1 in 10,000,000,000,000,000,000,000.
Grifman wrote:It is entirely possible that the likelihood of life developing more than once is so low as to outweigh the size of the universe. Maybe, maybe not. But nowhere have you attempted to quantify this probability based upon any scientific basis.
Actually, I did calculate exactly that in the other thread, in the context of my incredibly remote estimate of the probability of life. Given the number of iterations available, the probability that life would develop only once, was twice as remote as the possibility that it would develop at all (1 in 10,000,000,000,000,000,000,000,000,000,000,000,000,000,000). Or, to simplify it so that one could process it in a reasonable fashion, the probability that life would develop once and only once is equivalent to the probability that you would flip a coin 200 times and get only one head.
Assuming that the probability of life is as remote as 1 in 10,000,000,000,000,000,000,000 of course.
I'll give you a perfect example from the links I gave above. According to scientists, not only do solar systems have a habitable zone but so do galaxies. In our own Milky Way only 10% of the stars exist in this habitable zone. So in just one fell swoop, looking at one variable
, science has knocked out 90%
of your septillion stars (assuming for the moment that this also applies to other galaxies - we can go futher into galaxy types if you want to). The universe just got a lot smaller
Uh, no, it doesn't quite work that way. Your statistics really is rusty.
You are providing the data points that go into calculating the "1 in 10,000,000,000,000,000,000,000" probability of life, not directly reducing the number of iterations. You don't get to double down and do both. You can reduce the sample set of stars to 100 sextillion, but if you do that, you have to remove that factor from the probability of life side, which increases the probability of life to 1 in one sextillion.
And thus the equation ends up with the exact same results as before.