Maths says that we're nearing the end of human life!

[Xei]

There's a fantastic statistical argument that I read today, in a book about how the world could possibly end. It's really hard to get your mind around, and it's definitely not uncontroversial, but still pretty damn interesting. I thought you'd like to fight about this one. Okay, it goes like this: Rougly 10% of the humans that have ever been alive are currently alive now (this is a fact. It's due to the population explosion in very recent years). The philosophical/statistical argument is one of 'statisical medioctrity': say you perform some process to get a random number, for example, taking part in a raffle. If you get the number 100, what would be a good guess for the total number of tickets that are in the raffle? It's certainally not less than 100, and if it were, say, 1,000,000, it would be very unlikely that you picked out a ticket with such a small number. In fact, if you know no other information, then the safest bet would be to say that there were 200 tickets, and you got the middle variable. This is statistical mediocrity. Now we apply this to the human race, and our place within it. The basic statement is this: It is statistically probable that, where n is the total number of humans there ever will be, we are human no. roughly n/2 (ask if this maths needs further explanation. I think it should be quite simple though). So, in other terms: if the human population were to continue to expand, or simply stabalise and continue for millennia, we would be among, say, the first 1% of humans ever. This is a slim chance, and means that human population continuing is very unlikely. It's also very unlikely that we're among the 0.1% of the last ever humans. Because the population has exploded in recent times, this scenario would mean the Earth ending in less than a year. However, because population is just growing at a faster and faster rate, it may not be very long at all before the number of humans ever alive has doubled. That scenario would mean we're roughly in the middle of the numbers of 'every human ever', which is likely. So, to conclude, according to statistics, human life will probably have ended by the end of the 21st century. I'm sure you have some thoughts about this.

[Harrycombs]

If some one said the same thing 1000 years ago, wouldn't it seem to apply to them? Wouldn't they get the same results? It doesn't make that much sense to me.

[Seeker]

Ain't statistics grand??? I'm hoping that people will get a clue and stabilize the population at a sustainable level.

[Goldney]

Aye he makes a good point. As well as this the population will never double as the governments will simply introduce number of children per family laws, as they have done in China.

[Arachanox]

Math also says that in 50 billion years, all matter will split apart into their basic forms and all space and time will cease to exist. Your point?

[Alric]

Thats basicly a fancy way to say your guessing.

[Pyrofan1]

%47.3 of statistics are made up on the spot.

[Lseadragon]

Was that in the book Time by Stephen Baxter?

[sourcejedi]

I've read it and its fun, but that argument doesn't actually make any sense. It's extremely anthropocentric. It says: I, a human, could have been born into any era of human existence. I was born in this era, which has a probability dependant of the number of humans within each era... What makes you a human? Maybe the raffle you entered was for any organism, levels of which have probably remained roughly constant for a long time due to the staggeringly vast numbers of smaller organisms. What the hell is this raffle anyway? Who's running it? It sounds to me much like fallacious arguments based on the "law of averages", e.g. that if you rolled a fair dice 5 times and don't get a 6, you're more likely to get a 6 the next time you roll the dice. It might sound like common sense, but it's also plain wrong. Like Harry said, most people in human history could make this argument, and most of them would be wrong. It's just a clever way to take advantage of the way people like to think the end of the world is coming. Which is a pity because there are interesting philosophical arguments based on good maths that might strengthen a work of SF, but I really don't think this is one of them.

[arby]

1 = 2 The worlds gonna implode soon. I can feel it in my bones.

[furryrabbit]

Does the math not fail to encompass unforseeable events which would lower the human population (endemics, wars, nature)?

[Oneironaught]

I've read it and its fun, but that argument doesn't actually make any sense. It's extremely anthropocentric. It says: I, a human, could have been born into any era of human existence. I was born in this era, which has a probability dependant of the number of humans within each era... What makes you a human? Maybe the raffle you entered was for any organism, levels of which have probably remained roughly constant for a long time due to the staggeringly vast numbers of smaller organisms. What the hell is this raffle anyway? Who's running it? It sounds to me much like fallacious arguments based on the "law of averages", e.g. that if you rolled a fair dice 5 times and don't get a 6, you're more likely to get a 6 the next time you roll the dice. It might sound like common sense, but it's also plain wrong. Like Harry said, most people in human history could make this argument, and most of them would be wrong. It's just a clever way to take advantage of the way people like to think the end of the world is coming. Which is a pity because there are interesting philosophical arguments based on good maths that might strengthen a work of SF, but I really don't think this is one of them. What jedi said. It just doesn't hold up to any kind of realistic scrutiny because it's nothing more than a cutesy number/word game.

[Xei]

Please don't attack me for 'promoting' this, I made it quite clear that I just thought it'd be interesting to discuss. But yeah, the logic would seem not to work, although it seems very hard to disprove mathematically. You can do it by example like a few have you said though, I think... for example, if you don't consider humans, but all concious life... you can make the same argument say a completely different thing. Also, they say the universe will go on expanding forever. But we're only a few billion years into its history. Isn't that extremely unlikely? So that would also seem to undermine the argument's logic (although perhaps we're halfway through the habitable lifespan of the universe... ).

[Neruo]

What if you apply this to crocodiles or something like that?

[Original Poster]

Learn biology, there are population caps that species don't naturally ignore unless they're bacteria. Our population exploded because 1. the industrial revolution, 2. the invention of credit which made famlies think they're were way more wealthy than they actually are. There will be no new baby boom unless the government can come up with another way for people to think they have more resources in their enviornment than they actually do.