Overpopulation is a big concern for a lot of people. There are 7 billion people on this planet, and finite resources. The responsible thing to do is to have 2.1 kids, or less. "Zero population is the answer my friends..." Humans are the worst thing that have ever happened to this planet, and if there were less of us, the world would be a better place. If everyone had 8 kids, the results would be disasterous!
Yes, when I was in college I had to read Mathus's Essay on the Principle of Population. It was a required class I took my last semester in order to graduate. "Life Science", they called the class. Believe me, I am aware of the argument. I disagree. OverpopulationIsAMyth.com does a better job at debunking this idea than I can. Check out their website for more videos, studies, and facts.
Is overpopulation a problem we are facing today? Far from it. Japan is not the only country with an aging population. Europe is filling more coffins than cribs. In Russia, Putin has openly confessed that the biggest trial his country is facing is that there aren't enough babies. Europe and Russia have tried offering financial incentive to families for having children, but it hasn't helped. This is a very serious problem facing the world today, and is contrary to what we have been taught in school. From a non-religious perspective, the reality is that human beings, precious little babies, are the world's most valuable resource.
Demographic Winter is a recent documentary that explains these issues in greater detail.
As far as finite resources argument, I confess that yes, ULTIMATELY the world could run out of resources, but we aren't there yet. Not even close. From my Judeo-Christian heritage comes the command to multiply AND replenish the earth. We are told to take care of the earth, and to fill it.
I love mother nature and I strive to protect our natural resources in a number of ways. We buy in bulk. We downsized our home. We recycle. We use sustainable, green cleaning products. We use cloth diapers. We often purchase organic and/or locally grown food. These lifestyle choices are different and distinctly separate from our decision to have a large family. Choices like this are obviously better for the earth, no controversy. Having a large family does not contradict that choice. We are striving to raise a large family. My children are the best gift that I can give the world.
Is having a large family a selfish thing to do? Really? I suspect I'm preaching to the choir, but I'll let you decide for yourself.