These sorts of graphs are misleading insofar as they tend to lead-us-all headlong into a sense of complacency about the number of passengers on this precious, one-off Spaceship-Earth.

Some will subconsciously assert, -Look how many are in China, or India -and play down and ignore the population growth of their own country.

The Malthusian observations hold true. Food and contentment -equals people. Well-fed and over-sexed men AND women assure that.

Later theorists have contented themselves with ignorance -like the many who are inclined to lazy-agreement, that the Malthusian equation will eventually break-down, peter-out, -as populations become more educated, or, more affluent.

We are not becoming more educated.

And we -much more clearly- are not becoming -more- affluent.

Poor-uneducated people breed like rabbits -until the apparently endlessly increasing supply of poor, uneducated people degrades the environment enough, human beings lose either their contentment -or- their ability to fight off the debasements of over-population.

Here's an historical graph- China-India-Africa-Latin America-Western Europe-U.S. over the last 500 years-

http://www.visualizingeconomics.com/2007/12/09/comparing-population-growth-china-india-africa-latin-america-western-europe-united-states/

Note when the population of the U.S. equals the historical population of India, and China.

Consider the nearby date of the historical beginning of the U.S.

Blink your eyes, -twice if necessary.

Real leadership, would be opposed to "growth" regardless the hesitation this would pose for economists.

A leadership-pause is in order -long enough to tell the rest of the world, we are momentarily content to see if restraining our population growth - aids our human potential and enjoyment in these short trips we call, -life-.

In my opinion -this approach would mean real progress for civilization -especially in our economic understanding of this unforgiving-reality we MUST accommodate -or- pay the Piper when the bill comes due for our malfeasance.

But -religiously-inspired-humanitarian-types will say, who is to say when enough is enough?

It's a valid question I will answer.

To these blind numb-skulls, in return I will ask, How much more pollution, disease, pestilence, poverty, war AND GENERAL SUFFERING is needed -BEFORE- you say there is enough then?

There is no particularly necessary-rush to have another billion humans on the planet, -of which I am aware -anyway.

Enough is enough, and even MORE-THAN-ENOUGH of a lot of things, -NOT just human beings.

Make a list. No! -Make two lists.

Make first -a list of things there are not enough of. This will be the shorter list of the two lists.

And then make a list of things there are too many of.

Perhaps, in the mean time -as we all make our lists-, -enough time will pass- we will expire before the world is degraded much more during our own -short but selfish existence.

The future might then thank us -by making their own lists, before they get carried away remodeling the place to their own gauche tastes.

I just want to take a second to respond to the pessimism of Don's comment.

Is an expanding human population good, bad, or neutral? You seem to say bad, but I would argue it's neutral. There is certainly a maximum capacity for the planet, but we aren't all that close to it yet (unless we hit major bumps on the road from fossil fuels to alternatives; energy availability makes capacity vary widely).

People starve to death today but it's not because we don't have the technology or capacity to feed them. It's primarily a result of corrupt or inept governance.

Every extra mouth to feed is an extra brain producing output as well as a strong back. Occasionally an Einstein or a Tesla comes along and contributes an inordinate amount of good to the human condition. It was innovation that allowed for the population boom of the 20th century.

More people may mean more pollution, but it doesn't have to mean all that much more pollution. Lifestyle choices are the main contributor to pollution today, not sheer numbers.

When will the growth stop? When the market demands it stop. The higher the demand for a good, the higher its price and the inverse is true of supply. This will eventually extend to markets such as food and living quarters in ways that today's government prevents. Future wages can be expected to provide less leisure than we (Americans) have grown accustomed to, but with any hope will be more closely tied (with the aid of computers) to actual productivity.

Eventually markets will also be forced to account for ways in which they diminish nature that are ignored in today's prices. Business likes to ignore hidden costs as long as possible, but it will not be possible forever. For example a fishing company will have to consider world-wide fishery stocks and price accordingly to ensure its long term profitability.

So again, bad governance is the enemy, not growth. The future is guaranteed to be hungrier, but if it's starving it will be because of governmental corruption or ineptitude.

Hmm, I would suggest the planet has already been overgrown by humans. The only reason we can continue to grow enough food is because we're degrading the land that produces it and simply borrowing from the future (especially wrt oil, not only for transport but for the artificial fertilisers required).

Even more-so for the oceans which are on the bring of collapse.

e.g. http://www.abc.net.au/science/articles/2010/09/03/3001494.htm

People evolved to breed like rabbits to deal with being on the edge of survival at the whim of the elements. Once man was able to control those elements the eventual outcome was guaranteed.

All it takes is enough time.

Acknowledging one, I do not mean to encourage responses to my comments. I will re-focus on some obvious common misconceptions that have cropped-up, -mistakes that have the world on its current reckless course.

The dichotomy inserted between technology-and-humanity is disaffecting recognition that -humanity has been on a scientific-trial-and-error course -building frail and complex technological crutches -that have made these bloated human populations possible.

These populations are now being let adrift -due to the ongoing social collapse- crowded into conditions otherwise insufficient to maintain any of the basics of human dignity or long-term healthy-sustenance.

Our species is NOT stronger due to science. It has instead foundered in the wreckage of a compacted, fragile, scientific existence -created largely- since the Enlightenment.

This phenomenon has truncating the potential of EVERY human life. The Enlightenment-fashioned-world is NOW beset by poisonous pollutions and systemic failures of critical systems -systems created by an overly optimistic, pragmatic culture intent on aggressively cutting a dangerous path into an ever more perilous future.

Humanity ALREADY COULD BE walking-dead -thanks to science.

There is a misguided belief in the ability of some-scientific-genius to continue indefinitely solving the increasing problems arising from the previous meddling of other such tinkers. Generations of scientists -no less deluded than this generation- have meddled with an infinitely complex reality creating temporary solutions, -every one of which- has always broken down, always leaving worse problems than these efforts were meant to address.

The constantly whirring machinery of this infinitely complex Universe of reality is unforgiving of those who make too many assumptions about genius and competence.

The too often asserted god-like-proficiency is never real. We are three centuries from the Enlightenment. Planes still crash; buildings still burn; plagues still riddle our communities, and all are more deadly than before.

Because of THAT WHICH these scientists have degraded the planet, -EVEN IF- for the next three centuries it were somehow possible to make everyone cease the reckless preponderance of scientific pursuit -AND EVEN IF- humanity could reverse scientifically-enabled population trends, humanity likely could not in three centuries more -resurrect the life-sustaining potential of a single Earth continent.

We do seem doomed -to a continued scientific meddling with the planet. We seem on a highway headed to Hades -in a hand-basket -paved with our god-aspiring intentions, following directions handed-out with the assurances of genius -each- that really has no clue about what is going to turn up in the future -due to their faulty, blind assumptions.

All these scientists are individually using the world in trial-and-error experiments -conjured- as if by new-age-Gandalfs -who have the intention of creating a-cult-of-genius surrounding their individual, and absurd -god-aspiring- persona.

Altruists will say -just as if there really were a social psyche with god inspired -consciousness- "WE-ARE headed in the right direction. And science is OUR only hope."

The social psyche is a myth. -In reality- WE are just letting generations of individual pretenders PLAY GOD WITH THE WORLD.

I write not to cast a gloomy pall over this wonderful world.

I write to shed a bright light on the immorality of genius-worshiping.

Don, that's all fool-drool.

Population will peak at ~8bn in 2030.

We are a couple of years away from the early roll-out of unlimited power sources with 0 pollution, ate 5% of current costs.

Humanity will shortly thereafter have access to solar system resources millions of times greater than those ever extracted from Earth's crust.

Your consternation will be epic!