Based on _what_? Have you actually crunched any numbers, however casually? Have you looked at population trajectories? Have you considered that most people don't live at, or even anywhere close to, your elite level?
While far from definitive, I do play with world population numbers on occasion. My guestimate of world carrying capacity is around 33B people. Sure, it's not what you're used to, but it's sufficient (albeit mundane) food and shelter.
Population replacement rates are falling worldwide. World population is set to peak mid-century. Many first-world countries are facing population reduction at crisis rates, with a few having birth rates so low the country/culture is set to disappear entirely. Insofar as some think there should be fewer people, seems the species is pretty good at handling that without wanton interference.
"Too many people" is easy to say when you're very comfortable, assume everyone else lives as you do, and don't like the idea of having to give way to a few more. Don't forget that half the world's population functions under 1/20th of the official American "poverty line". Funny thing is, if "we could all afford to live like we do today" we'd be complaining about how bad off most people are and arguing for a population reduction to 0.5-0.9 billion so the survivors could live like the top 10%.
In the past (exemplified by _The_Population_Bomb_) similar predictions were made lamenting the world's inability to support X billion people; we're well beyond those feared limits now and doing quite well. Technology (notice which discussion board we're on here) is very good at working out ways of drastically improving resource providence. The problem with food isn't lack thereof - thanks to technology we have more than enough for everyone; the problem with food is politicization of distribution. Insofar as some resources really are limited (and there are valid arguments that fossil fuels et al are not nearly as limited as naysayers claim), high tech enables better/cheaper/sustainable solutions. Problems can be resolved with solutions, some of which are unimaginable now but will be normal in the not-far future.
So the question remains: on what objective grounds can you claim "there is simply too many people in the world"? Why can't Y-Combinator types view the "too many" problem as a challenge for making 7-10B people sustainable & comfortable? 1-2B is a heck of a reduction, presumably beyond mere curbing of procreation; as others ask - are you willing to sacrifice yourself and/or [potential] offspring to get there? and how far are you willing to go to enforce the view on those of us who disagree?
If there were fewer humans, the price of resources would drop, so we'd start using more of them frivolously, resulting in no significant benefit.
On the other hand, if there were more humans, the price of resources would rise, and we'd start using them more efficiently.
Quick quiz: what's the only commodity that has consistently risen in inflation-adjusted cost over the last few centuries, signalling that demand is greater than supply?
Answer: labour.
The large population of the world is what has allowed the intense specialization of the modern economy, leading to the technological revolution. Without the technological revolution we'd still be burning wood for heat, which is far more harmful on the environment than what we currently do, just to name one effect.
Energy can be turned into food in a limited space very efficiently. Back of the envelope calculations show that a few hundred large nuclear power plants could feed the entire world. The only reason we don't do it this way is because it's cheaper to use the sun as a power source.
That says something about the US, but nothing about the world. In the same time period the median wage across the world has increased dramatically, especially in China, India & Africa.
I suspect that the real average wage in the US would decrease quickly if falling wages weren't inconvenient to sitting politicians.
Or it might say that the US has access to lower wage labor in other countries.
Either way it says nothing about the global value of labor.
The thing is, we're always on the verge of disaster, but the price mechanism of the market continually motivates people to seek out alternatives. So we always find a new way to achieve something "just in time".
Consider the history of lighting. There's no way we could continue to light our homes with candles or whale oil; as the whales got scarce, the price of oil increased, and that's a big part of what drove the invention of newer means of generating light.
The fact is that the single greatest resource at our disposal is the human mind: that's what allows us to invent new alternatives, to get away from the things that become scarce. All of human history shows that the more people we've got, the better off we are.
There are probably 1 billion people in the developed world enjoying a life of "consumerism, fossil-fuel burning and so on", plus a tiny minority composed of the elites of the global south. You may add roughly another billion people from the emerging economies (i.e. the BRIC countries), who have lesser, but rapidly growing, rates of per capita consumption.
We are already 1-2 billion people living what we'd consider a "normal life" by modern standards, maybe another 3-4 billion with tolerably low levels of resources, and 1 more billion in the most absolute poverty. Heck, I have not seen any study to confirm, but I suspect that the average pet in the US is better taken care off that the average child in a 3rd world shanty town (and probably have a longer expected lifespan too)!
So, yes, the population bomb is a problem, but it gets amplified by the per-capita expenditure, and the 80-96 percentile have a disproportionate weight on the overall effect.
(Contrary to OWS retoric, my opinion is that the "one percenters" are not the main part of the problem. They are not only too few, but subject to time and space limitations that prevent them to consume as much as their wealth would predict. At the end of day, they will use most of their money to make more money or gain political influence. What they use that influence for is yet another dimension of our predicament).
Their primary complaint is that the 1% have already used their money to gain political influence to advantage the further consolidation of existing wealth and to disadvantage those who would make new wealth, potentially at the expense of the existing 1%.
It has nothing to do with other consumption, or lack thereof, of the 1%.
We are not in this situation because some evil overlord made us do it, but we ended up here due to our collective needs and wants. And the way out is not by opposing an overlord that may turn out not as evil and definitively not as in control and we had imagined, but through the conscious modification of our needs and wants.
But all of that is an aside to my point, which is that you are still either mis-understanding or mis-representing the OWS position as something of a "blame everything on the 1%" philosophy.
OWS has a very narrow platform of "money has corrupted politics". The fact that OWS was roundly criticized as not having a point is attributable to the fact that the Occupiers didn't agree on much beyond the statement of the problem. That is: they all agreed that money needed to be taken out of politics, but they disagreed on whether, say, ethanol subsidies were necessarily bad, or GM seeds were causing problems in the developing world, etc.
Some of them obviously believed in those things. Others just wanted to see an end to 'too big to fail' and socialized losses. But those were not 'occupy's positions.
The shortage of resources that comes from overpopulation is a problem which needs to be solved in the long term. However it wouldn't be a problem just yet if it weren't for a handful of people hording the majority of the world's wealth. The problem at the moment isn't a lack of resources, but rising prices due to a shortage of resources. If income for middle and lower class families hadn't been stagnant for the past decades then those rising prices wouldn't have been a problem. That's what people are protesting. It's not a class warfare, it's not a hatred towards people who are well off (like myself). It's about needless suffering.
I better leave it at that.
Irrespective of whether they are the main part of the problem or not, I think that demonising them is a really stupid idea that just plays towards divide and conquer politics. Ideally they should be co-opted as much as possible, mainly because they currently have most of the money.
Arguably if we had better technology, even an increase over current population could be an improvement (assuming a marginal extra person was engaged in productive activity); most of the constrained resources seem like they could be dealt with using cheaper energy (making recycling/low grade ores/etc. recoverable, better transportation to reduce crowding, dealing with pollution, etc.)
Barring people who are already suicidal, I doubt anyone would want to volunteer. This is a hard problem, well beyond the concerns of political correctness.
However, you bring up some good practical points of the consequences. A person's life ripples out and touches other people around him.
As I said, this is a hard problem, not one solvable simply through a die-off or a cap on reproduction. At the heart of the problem is that each of us are self-centered to the point of ignoring anything beyond ourselves. We're already zombies in a culture of mindless consumerism.
In First World countries, if you take away an individual's "job", "work", and "productivity", then that individual is lost. He does not know why he is here or what his purpose is. All he knows is that he needs to pay his rent and mortgage, watch TV, raise a family, and go shopping. People who do not fit that mold is either outcast or assimilated. Braaaaiinns. A few people might see beyond it thinking, let's do a startup! but end up mindless hitting the refresh button to see new comments on HN.
Heh, zombie apocalypse is already here, and we didn't even see it coming. Though we did make some great TV shows about it.