Kurzgesagt - Why Alien Life Would be our Doom - The Great Filter

[Silly Sil]

[QUOTE=_Axel;53104008]The point is it's irrelevant to make up explanations for the absence of visible alien lifeforms when us being blind is the limiting factor anyway.[/QUOTE]
Yeah sure, you are right here. Just because we don't see them doesn't mean they aren't there.
[QUOTE=_Axel;53104008]No. It won't happen by 'pure chance' unless the probability is high enough.[/QUOTE]
But wouldn't something being possible mean it's almost inevitable on the cosmic scale, given the size and timeframe?
Wouldn't it be like having a change to win a lottery of 1/million but you can "play" it a thousand times a second for 10000 years? So even if the probability of life occurring is very low the number of planets that can sustain life is high enough that it almost definitely happened somewhere else as well, no?

[AxeI]

[QUOTE=Silly Sil;53106897]But wouldn't something being possible mean it's almost inevitable on the cosmic scale, given the size and timeframe?
Wouldn't it be like having a change to win a lottery of 1/million but you can "play" it a thousand times a second for 10000 years? So even if the probability of life occurring is very low the number of planets that can sustain life is high enough that it almost definitely happened somewhere else as well, no?[/QUOTE]
What makes you think the probability of life appearing isn't as astronomically low as there are astronomically high amounts of stars in the universe?

It's possible for a single man to be struck by lightning, win the lottery, become president of the US, go to space, win the Olympics, and live to be 120 years old, all in a lifetime. That doesn't mean such a man exists, even though there are 7 billion people on this planet. Individually, each of these events are improbable, but probable enough for a few people on this planet to occasionally experience. The thing is, the probability for two of such events to occur on the same person is the product of the probabilities of one such event, so one in a million becomes one in a trillion, one in a quintillion, and so on...
If life is the result of such a succession of highly improbable events, then it isn't inevitable for it to form in an universe, as big as it may be, let alone form on several planets.

[Silly Sil]

[QUOTE=_Axel;53107164]What makes you think the probability of life appearing isn't as astronomically low as there are astronomically high amounts of stars in the universe?

It's possible for a single man to be struck by lightning, win the lottery, become president of the US, go to space, win the Olympics, and live to be 120 years old, all in a lifetime. That doesn't mean such a man exists, even though there are 7 billion people on this planet. Individually, each of these events are improbable, but probable enough for a few people on this planet to occasionally experience. The thing is, the probability for two of such events to occur on the same person is the product of the probabilities of one such event, so one in a million becomes one in a trillion, one in a quintillion, and so on...
If life is the result of such a succession of highly improbable events, then it isn't inevitable for it to form in an universe, as big as it may be, let alone form on several planets.[/QUOTE]
Your entire post is just a long winded "but the chance could be extremely low", you didn't really add anything new to the discussion.
And your analogy is a bit manipulative since you've given examples of limited events (there haven't been millions of US presidents and Olympics) and some that pretty much exclude each other.

If we were to assume that we are the only ones because the probability of life appearing is as astronomically low as there are astronomically high amounts of stars able to sustain life in the universe that would be one cosmic coincidence, a frigging God's intervention. It's a giant leap of faith. I think it's far more reasonable to assume that whatever we observed in the universe (like saturn's rings for example) it probably happened somewhere else as well.

[AxeI]

[QUOTE=Silly Sil;53107226]Your entire post is just a long winded "but the chance could be extremely low", you didn't really add anything new to the discussion.[/QUOTE]
What? No? Your point was 'even if the probability is low the universe being big means it's inevitable' which completely ignore the fact there's no hard limit for how low a probability can get and how easily a probability can be reduced to nothingness if the event it represents is comprised of several improbable ones, which is what I pointed out.
[QUOTE]And your analogy is a bit manipulative since you've given examples of limited events (there haven't been millions of US presidents and Olympics) and some that pretty much exclude each other.[/QUOTE]
The point of the analogy is to illustrate how probabilities multiply and an event can quickly become virtually impossible even if technically possible due to the fact the resulting probability is astoundingly low.
[QUOTE]If we were to assume that we are the only ones because the probability of life appearing is as astronomically low as there are astronomically high amounts of stars able to sustain life in the universe that would be one cosmic coincidence, a frigging God's intervention.[/QUOTE]
It may very well be even more astronomically low, it may be less astronomically low. The point is [I]we don't know.[/I] A single civilization is not nearly enough to make a statistical study, and to infer that just because we exist means there are other civilizations running around the galaxy is baseless.

[Silly Sil]

[QUOTE=_Axel;53107257]The point of the analogy is to illustrate how probabilities multiply and an event can quickly become virtually impossible even if technically possible due to the fact the resulting probability is astoundingly low.[/QUOTE]
Yes I understood the point of the analogy, I don't know why you are explaining it again. I'm saying it's manipulative because there's a limited number of Olympics and US presidents while there is no arbitrary limit of how many times and at which times life could occur. And the point of the analogy is no more than to say "the probability of life occurring could be really, really low", something that you've stated in the first sentence of the post that analogy was in.
[QUOTE=_Axel;53107257]What? No? Your point was 'even if the probability is low the universe being big means it's inevitable' which completely ignore the fact there's no hard limit for how low a probability can get and how easily a probability can be reduced to nothingness if the event it represents is comprised of several improbable ones, which is what I pointed out.

It may very well be even more astronomically low, it may be less astronomically low. The point is [I]we don't know.[/I] A single civilization is not nearly enough to make a statistical study, and to infer that just because we exist means there are other civilizations running around the galaxy is baseless.[/QUOTE]
You are presenting this as the option that the probability of life occurring is just as astronomically low as there's astronomically high number of planets (and therefore we're the only ones) and the option that the probability of life occurring is any higher (and therefore life exists somewhere else as well) are equally possible so you will withhold any judgement on because to assume either is "baseless assumption".
Don't you think it would be a leap of faith to assume the former? It's like saying "Earth being the only planet with water in the entire universe is equally likely as there being more planets with water". Sure we don't know which one is the truth but one is more likely than the other, no?
I mean if you know that something can happen by natural means, like say a lightning hitting the ground, it's more reasonable to assume it can happen again than it would be to assume that one time was the only time it happened and will never happen again, don't you think?

[AxeI]

[QUOTE=Silly Sil;53107516]Yes I understood the point of the analogy, I don't know why you are explaining it again. I'm saying it's manipulative because there's a limited number of Olympics and US presidents while there is no arbitrary limit of how many times and at which times life could occur. And the point of the analogy is no more than to say "the probability of life occurring could be really, really low", something that you've stated in the first sentence of the post that analogy was in.[/QUOTE]
I was explaining it again because you kept getting hanged up on irrelevant aspects of the examples. Replace US presidency and Olympics with other improbable events related to non-singular occurrences, that doesn't change anything about the argument.
[QUOTE]You are presenting this as the option that the probability of life occurring is just as astronomically low as there's astronomically high number of planets (and therefore we're the only ones) and the option that the probability of life occurring is any higher (and therefore life exists somewhere else as well) are equally possible so you will withhold any judgement on because to assume either is "baseless assumption".
Don't you think it would be a leap of faith to assume the former? It's like saying "Earth being the only planet with water in the entire universe is equally likely as there being more planets with water". Sure we don't know which one is the truth but one is more likely than the other, no?[/QUOTE]
One is more likely than the other because water is a simple molecule formed with relatively basic atoms that are abundantly present in the universe, which we already know is present in other celestial bodies (Comets are basically made of ice). But does the sole fact Earth has water makes it more likely that there are other planets with water on them? Not really. It just means it's possible.
[QUOTE]I mean if you know that something can happen by natural means, like say a lightning hitting the ground, it's more reasonable to assume it can happen again than it would be to assume that one time was the only time it happened and will never happen again, don't you think?[/QUOTE]
I don't think so, no. It just means it's possible, it doesn't say anything about how likely it is to happen again.

[Silly Sil]

[QUOTE=_Axel;53107993]I was explaining it again because you kept getting hanged up on irrelevant aspects of the examples. Replace US presidency and Olympics with other improbable events related to non-singular occurrences, that doesn't change anything about the argument.[/QUOTE]
Sure I got the argument I just thought it was a bit manipulative in the way you presented it.
[QUOTE=_Axel;53107993]One is more likely than the other because water is a simple molecule formed with relatively basic atoms that are abundantly present in the universe, which we already know is present in other celestial bodies (Comets are basically made of ice). But does the sole fact Earth has water makes it more likely that there are other planets with water on them? Not really. It just means it's possible.

I don't think so, no. It just means it's possible, it doesn't say anything about how likely it is to happen again.[/QUOTE]
Look at it this way. You know that I rolled a dice 10 times and you know that it gave me a 1 at least once, but you don't know how many sides the dice has and your goal is to guess that number of sides. Your safest bet is that the dice has 1 side (or as few as possible). The more sides you pick the less chance of you being right, no? It's safest to bet my dice has 1 side and I rolled one ten times and then I chose one those rolled ones to present to you than it is to bet that my dice has 100 sides and I rolled 1 with 1% chance and showed it to you. Similarly it's safer to bet we are one of many many civilizations than to bet we are the only ones. Am I wrong on this? I can be totally wrong on this.

[AxeI]

[QUOTE=Silly Sil;53109168]Sure I got the argument I just thought it was a bit manipulative in the way you presented it.[/quote]
It can't be since the outcome of the argument doesn't depend on those specific examples. I think you're being too paranoid.
[Quote]Look at it this way. You know that I rolled a dice 10 times and you know that it gave me a 1 at least once, but you don't know how many sides the dice has and your goal is to guess that number of sides. Your safest bet is that the dice has 1 side (or as few as possible). The more sides you pick the less chance of you being right, no? It's safest to bet my dice has 1 side and I rolled one ten times and then I chose one those rolled ones to present to you than it is to bet that my dice has 100 sides and I rolled 1 with 1% chance and showed it to you. Similarly it's safer to bet we are one of many many civilizations than to bet we are the only ones. Am I wrong on this? I can be totally wrong on this.[/QUOTE]
If you think my example was being manipulative you should've refrained from using this one.
On a dice, every side has the same probability of coming up. Real world events don't. Your example isn't applicable.

[Silly Sil]

[QUOTE=_Axel;53109610]It can't be since the outcome of the argument doesn't depend on those specific examples. I think you're being too paranoid.[/QUOTE]
... That's why I said I understood your analogy even though I pointed out it's a bit manipulative because you gave it limits that aren't there when it comes to planets. I think you are being too defensive. I understand the point even though I think it was a bit flawed okay? Can we get over it now?
[QUOTE=_Axel;53109610]If you think my example was being manipulative you should've refrained from using this one.
On a dice, every side has the same probability of coming up. Real world events don't. Your example isn't applicable.[/QUOTE]
How is it not applicable? What does it have to do with anything that the probability of every side coming up is the same? We're only counting when it gives us a "1"... Depending on the dice you are throwing the chance of getting 1 will be 1/4, 1/6 1/10 and so on. What are you talking about?

[AxeI]

[QUOTE=Silly Sil;53109659]How is it not applicable? What does it have to do with anything that the probability of every side coming up is the same? We're only counting when it gives us a "1"... Depending on the dice you are throwing the chance of getting 1 will be 1/4, 1/6 1/10 and so on. What are you talking about?[/QUOTE]
It introduces a bias because it seems more reasonable to think a dice has few sides than millions of them.
Furthermore it isn't applicable because your example doesn't account for survivor bias. The reason we're here to discuss this in the first place is because we rolled a 1 when it comes to life forming on our planet. So it's natural that we witness this occurrence no matter how unlikely it is to happen. If we want to explain this in your example's terms it's as if you rolled the dice an extremely high amount of times and only officially started the experience once you rolled a 1. Thus of course you're going to have a 1 among those ten rolls. It isn't indicative of the likelihood of rolling a 1.

[Silly Sil]

[QUOTE=_Axel;53109730]It introduces a bias because it seems more reasonable to think a dice has few sides than millions of them.[/QUOTE]
You are right, you can interpret it this way. Apologies, it wasn't my intention. We can talk about a computer program giving us a random number then not a dice.
[QUOTE=_Axel;53109730]Furthermore it isn't applicable because your example doesn't account for survivor bias. The reason we're here to discuss this in the first place is because we rolled a 1 when it comes to life forming on our planet. So it's natural that we witness this occurrence no matter how unlikely it is to happen. If we want to explain this in your example's terms it's as if you rolled the dice an extremely high amount of times and only officially started the experience once you rolled a 1. Thus of course you're going to have a 1 among those ten rolls. It isn't indicative of the likelihood of rolling a 1.[/QUOTE]
You mixed it up, "rolls" represented the planets and their number doesn't change much in the end.

Lets go back to the beginning. All we know is that life happened at least once. We don't know the probability of life occurring on a life-sustainable planet and we don't know the amount of those planets. Do you agree on the premise?

Now you have to [I]guess[/I] what's the probability of life occurring on a life-sustainable planet. Okay?

My argument is the higher you bet that probability is, the better chance you have at being right. Because the less you bet, the more improbable that one time when life occurred was. In other words, it's more likely that the chance is high than low.

Now, I can give you math on this to show you this correlation and I'm pretty sure it's correct, however if we don't want to have an enormous spreadsheet on this we would have to agree to simplify it and reduce the number of planets and possible probabilities to small amounts. Is it acceptable for you, or do you think that reducing the number of examples would falsify the correlation? If it's okay with you, give me a number of planets and possible probabilities and what they are (for instance 4 probabilities: 100% chance of life occurring on a life-sustainable planet, 1% 0,001% and 0,000001%) you want me to present. I understand that reducing the number of planets and possible probabilities will make this inaccurate, but they are supposed to only represent a correlation.

[AxeI]

[QUOTE=Silly Sil;53109829]You are right, you can interpret it this way. Apologies, it wasn't my intention. We can talk about a computer program giving us a random number then not a dice.

You mixed it up, "rolls" represented the planets and their number doesn't change much in the end.

Lets go back to the beginning. All we know is that life happened at least once. We don't know the probability of life occurring on a life-sustainable planet and we don't know the amount of those planets. Do you agree on the premise?

Now you have to [I]guess[/I] what's the probability of life occurring on a life-sustainable planet. Okay?

My argument is the higher you bet that probability is, the better chance you have at being right. Because the less you bet, the more improbable that one time when life occurred was. In other words, it's more likely that the chance is high than low.

Now, I can give you math on this to show you this correlation and I'm pretty sure it's correct, however if we don't want to have an enormous spreadsheet on this we would have to agree to simplify it and reduce the number of planets and possible probabilities to small amounts. Is it acceptable for you, or do you think that reducing the number of examples would falsify the correlation? If it's okay with you, give me a number of planets and possible probabilities and what they are (for instance 4 probabilities: 100% chance of life occurring on a life-sustainable planet, 1% 0,001% and 0,000001%) you want me to present. I understand that reducing the number of planets and possible probabilities will make this inaccurate, but they are supposed to only represent a correlation.[/QUOTE]
I think you're mixing up the probability of life happening at least one time in the universe and the probability of it happening on a given planet, the former being higher.
If you can formalize your statement, that would be nice, it would clear that up.

[Silly Sil]

This should be correct unless I horribly misremembered something from that one probability class when the teacher asked a similar question (Lets say a program that gives random numbers gave me an number 5, if you were to bet how many other numbers it can possibly give, what would the safest bet be? And then we ran something like this, as far as I remember)

The numbers are arbitrary of course the only meaningful thing is how they increase/decrease in relation to each other.
[IMG]https://image.ibb.co/fQJXvc/prob.jpg[/IMG]
I hope I didn't fuck it up. It looks super counter-intuitive with planets on it.

Looking in a different way at it: You pressed enter and a computer program that gives you random numbers gave you a 5, which of these programs is the most likely that's running on the computer, one that only gives you a number between 1 and 10, one that can give you a number between 1 and 100, or one that can gives you a number between 1 and 1000? These options are not equally probable. It was most likely the one with the fewer options, the one with most probability to give you a 5, no?

Basically if you know that it happened at least once, the safest bet is to assume it happens as often as possible.