I really like this discussion because it's a rare example of things being discussed in real terms, where the financial considerations are secondary; actual power over real resources being wielded by the wealthy.

If you think about it in terms of resource consumption per capita over a lifetime then it gets a lot more difficult because now you have to divide all those resources across all of the humans that have lived and that will every live taking into account any kind of improvement on recycling. This is a really hard problem, the estimate is that right now about 7% of all that people that have every lived are alive, and that the total number of people have have ever lived is 117 billion people. But because historically people would consume less than we do today there is a 'surplus' that we started to eat into at the beginnings of the industrial revolution. Now we're in debt to the future and those 'wealthy' people in your comment are over represented in terms of resource consumption but we're not that far behind when compared to say the people from 400 years ago.

Extrapolating into the future then is probably going to show an even larger percentage of consumption per capita compared to the budget, and that at some point in time will result in a shortage. The people that will live through that will look back at us as the incredibly wasteful denizens of the 20th and 21st century that wasted resources on a scale that at that point in time probably will be criminal.

Sustainability is more than just a nice slogan, it is sooner or later going to be our end-game and the earlier we start doing this for real the longer the species will exist and the more comfortable the members of the species will be.

You make very interesting points, but I'm having some trouble understanding exactly what you mean.

When you say that at some point in time there will be a shortage, what do you mean, exactly? A shortage of what?

The way I understand capitalism is that shortages, in a sense, don't actually exist in free markets (except temporarily if there are unexpected disruptions), because capitalism is mostly a system of allocating the resources that are available, in the most efficient way that we know of.

Or another way of thinking about it, is that there is always a shortage of almost everything, because we could always take advantage of more resources if they were available.

So what do you mean exactly?

Resources are finite, they will eventually run out. All resources are finite except those that nature provides as part of its own sustainable cycle, everything else sooner or later comes to an end and the more of nature that we destroy the more we will have to provide ourselves. Resource availability has five stages: we don't have it because we can't get at it, we have access to it and we're actively getting it, getting it has become too expensive (you end up alternating between this one and the previous one for a while), we have to get it from our previous waste material because the original sources have all run out and finally we no longer have it in a form that we can get at it because it has become too dispersed.

Every resource that came as a gift with the 'bare' planet (before life began and exposed by various tectonic processes) follows these stages. So the more of nature we leave in one piece and the more we work in a sustainable manner (maximize recycling, for instance) the longer humanity will survive in a recognizable form. The only other way that I can think of is to go off-planet.