It wasn’t long after the invention of calculus that scientists started applying the concepts to population. They noticed that in some closed systems with non-renewable resources (i.e., bacteria in a Petri dish, perhaps Easter Island) the population would reach a carrying capacity and could then crash to low or even non-existent levels.
This lead to the rise of Population Alarmists. They are generally found in tenured positions in the academic world, think tanks, governments, or any other place where their job security has nothing to do with whether their predictions are correct or not. As an example, we have Stanford University professor Paul Ehrlich, whose 1968 book The Population Bomb started with the following dire prediction:
“The battle to feed all of humanity is over. In the 1970s hundreds of millions of people will starve to death in spite of any crash programs embarked upon now. At this late date nothing can prevent a substantial increase in the world death rate.” (The sentence was of course removed from the 1980 and later editions, as the world death rate fell sharply)
Ehrlich believed the only way humanity could survive is if the government sets up a “Department of Population and Environment” which would take “whatever steps necessary” including things like secretly placing sterilizing chemicals in the water supply, imposing high taxes on cribs and car seats, and figuring out how to abort only females.
Ehrlich agreed with the thesis in William and Paul Paddock’s book Famine 1975! that societies should be “triaged” on how well they would be able to feed themselves. None of them saw any way that India could do it, so they advocated cutting their losses and removing all food aid from the sub-continent. The Paddocks likened sending food to India to “throwing sand in the ocean” Fortunately, the 400 million Indians ignored the distinguished academics. Since 1960, India tripled its population, reduced the percentage of malnourished citizens from 90% to 40%, and gave the world many millions of engineers, doctors, and scientists.
In contrast to the Population Alarmists we have the Rational Technologists. These people don’t deny that humanity faces many problems, but also believe that the combined power of human ingenuity will be sufficient to solve them.
PA: “There is no way that humanity will have a large enough amount of resources long term to survive. The carrying capacity is around 10 billion. We are addicted to fossil fuels.”
RT: “The sun is literally a thermonuclear reaction thousands of times bigger than the Earth. So for the next 5 billion years or so we are good.”
PA: “Well people can’t eat sunlight.”
RT: “Only about 3% of the Earth’s surface area is currently used for growing crops. And that is just horizontal land. Vertical gardens could increase this number by many times. There will be improvements, of course, like how to grow an acre of food in 380 sq feet (and they’re stackable!) Of course, if there are 100 or 200 billion people, we won’t be eating many steaks.”
PA: “Sounds like you want some evil genetically engineered super crops!”
RT: “Genetic engineering of plants in and of itself is amoral. Farmers have been doing it for thousands of years. We just have more precise tools now. Some genetic engineering (increasing yield, etc) is good while some (suicide genes for next crop season, only working with certain pesticides) is bad.”
PA: “Well, how are you going to water all those crops?”
RT: “The earth’s surface is 71% water. Plus those oceans are pretty deep. Sure, it’s salt water, and reverse osmosis takes energy, but we already covered that.”
PA: “Well, crops need other things, like nitrogen.”
RT: “The Atmosphere is 78% nitrogen. With a total atmospheric mass of 5 x 10^18 kg, that’s 390,000,000,000,000,000 kg of nitrogen, plus what’s in the soil and water. Bacteria can convert that to a usable form for roots.”
PA: “Well, what about trace elements like potassium, calcium, etc?”
RT: “Again with the math? Please don’t make me calculate what % of the earth’s volume has been mined. I’ve been writing a lot of zeroes already. Besides, those trace elements are reusable.
PA: “But topsoil!”
PA: “Well we certainly won’t have space for all the waste we’ll generate.â€
RT: “The vast majority of waste is reusable or recyclable. Plus, things like 3d printers will vastly cut down on what each person uses.”
PA: “Okay, well we certainly won’t be able to fit those people anywhere.”
RT: “If the entire world was as dense as Manhattan, we would have space for 13,400 BILLION people. Now imagine how many layers of people could live underwater or floating cities.”
PA: “Well I just don’t see how the earth can ever hold even 10 or 20 billion people.”
RT: “That’s just the point. It’s not up to YOU to see it or come up with all the solutions. It’s up to the collective power of 10 or 20 billion human minds connected together. When survival is at stake for them and their children, is that power really something you want to bet against?”
According to the population alarmists, we’re always a decade or so away from mass catastrophe. The fact that it’s been over a hundred years of things moving in the opposite direction does little to dissuade them. One might think that the fact that if people had followed their advice the deaths and suffering that would have been caused would rival the body count of the worst dictators in human history would cause them to revisit their premise, but if anything it just causes them to dig in more. Ehrlich still claims to have been right. Just wait about ten years!
THIS time it’s really going to happen!
Author’s Note: This analysis is greatly simplified. Certainly, the presence of raw materials doesn’t mean that they will be economically feasible to extract. Obviously, something like mining the core of the earth would create its own challenges (although it could create space for a Gravity Train which could allow travel between any two points on earth in 84 mins and with no expended energy). The point of this analysis is simply to show that estimates of the earth’s carrying capacity being 70% reached are off by several orders of magnitude. Of course, it is unlikely that we will see anything close to the carrying capacity in our lifetimes. With the recent drop in birth rates, even the UN (a generally alarmist group) has a median projection that sees stabilization about 9 billion.