Yes, now we begin to agree.
It's true that we could live sustainably, provided we stop using cars and planes for everything, we live in smaller flats, we eat local and seasonal food, and stop buying so much crap.
Even though we could, the real question is if we ever will do so before it's too late.
The heavy smoker could also stop smoking any day in theory. But in practice?

I hope you're right for the demographic curve. I'm not so optimistic. WW2 didn't change much the demographics curve for example. You really need a shitload of famine/war/drought to kill a few billion people.

I'm talking about a sustainable society. There's not much sustainable about the way we do things right now. It's still too early to say if those people were indeed wrong when they said that it's not possible to feed 7 billion people.

Heavy smokers also tend to think that risks are grossly overestimated, and that there's no problem in smoking one pack a day for 30 years. 5 years later, many are dead after a long and painful illness.

Back to the original point : it's just not possible to sustain 15-20 billion people on Earth. Time will tell if 7 billion are even possible.
Moreover, you cannot extrapolate Israel example to the whole world. This country gets a lot of support from the USA and Europe, and doesn't see anything wrong with colonization.

We have plenty of oil, or did you miss the current drop in price?

Yes, a price drop automatically means there will be enough oil for everyone forever.
It has nothing to do with OPEC setting prices and the US destroying their environment in order to get the last few drops available.

As for Israel : https://en.wikipedia.org/wiki/...
I guess I know where a big part from the other 50% is coming from.

note that 114x background rate translates to ~225 species going extinct per million years

No. You don't seem to understand this E/MSY unit.
If you consider that there are 10 million species on earth (I agree with you, this number is a guesstimate, it could be off by 1 or 2 orders of magnitude), 225E/MSY would imply approximately 2250 extinctions per *year*.
If you consider just one species, it would go extinct 225 times over in a million years. In other words, its survival expectancy would be about 4500 years.
Shit, how old is our civilization?

carrying capacity of the earth is at least 15 perhaps 20 billion

No it isn't. It's just not possible to sustain our current world population and living standard without oil.

Israel seems to manage fine (though not without trouble and ingenuity)

Yes! Israel just takes all the water it wants, and leaves droplets to occupied Palestinian territories. How ingenious!

And when we don't have enough oil for everybody, we'll have a huge fucking problem.
Climate change and peak oil wouldn't be a problem at all with less than 1 billion humans on the planet.

Urban people have a smaller ecological footprint

Citation needed.
There's an ecological optimum somewhere between a hamlet and a megalopolis. If you live in a remote place, you need to take the car for many basic needs. If you live in a huge city, you need to import all your food, and export all your waste.

we're going to drive the bus off that extinction cliff while singing happy days are here again.

I *love* that song. And boy, look at that wonderful view!

When you say no to beta anal fisting, you still get it very slowly, one finger at a time.

You're both correct for X divided by zero. It's simply not defined.

But GP was right for "Y plus red" and "Z times pineapple".
Both are defined in a mathematical sense :
* If Y is an integer, "Y+red" is defined in the free abelian group on the generator {1,red}.
* My math is rusty, but "Z times pineapple" should be defined in a multi-variable polynomial ring.
You don't need physics to define any of them. You can draw parallel to physical units, but you don't need to.

Finally, you're free to think that math is a human invention. My personal feeling is that we discover math more than we invent it, but I guess we'll never know for sure.

lim x->0 x^2/x = 2

Let's pretend you didn't write it, okay?

Exactly.
On a related note, could we please kill the developer(s) that wrote the CSV import for Excel?
Depending on your regional settings, importing a cell containing 3.14 could yield 3.14, 3140 or 14th of March.

Sure, kill the messenger.
All those facts are well documented : feel free to look for other sources.
It's typical of this damn conflict. Both sides are so extreme that they consider any centerish point of view to be extremely biased.

http://www.theguardian.com/wor...
https://firstlook.org/theinter...

and from 2009 : http://www.hrw.org/fr/node/818...