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Thanks for sharing that, it really was a good resource. While he doesn't say so directly, he seems to imply that action doesn't need to be taken because it seems like the rate of population growth is predicted to slow down and perhaps peak at 11 billion. The problem with that admittedly cozy idea is that it's ignoring how already strained the human race is currently at 7 billion. Reducing our population right now would be excellent for humanity's overall health, so the thought that we "only" need to figure out how to support 11 billion is not exactly ideal. If reducing the population will benefit humanity, and I'm fairly sure it will, then I think it would be a good idea to work directly towards that.