Brief thought exercise: in a way, is actually having a child more selfish than not having one?

[youtube http://www.youtube.com/watch?v=ZSRgKms0gyg&w=620&h=315]

Alright, let's start here: I don't have kids but God willing (and maybe a job willing) later, I'd like to someday.

Now move to here: for years, the narrative has actually been based on the idea that it's selfish not to have a child.

But then consider this: there are close to 9 billion people …