What is the most important engineering problem of our future?

[Bill Moore]

Originally Posted by KenWittlief

getting as much food per acre of land is still a dead end path, if the world population continues to increase.

If we scaled the population back, then none of these things you mentioned would be necessary.

Theoretically you have a point; it just doesn't work in practice. Even in dictated societies where population control has been tried, they only succeeded in slowing growth down, never actually stopping it.

You argument is similar to the old Zero Population Growth movement (something like 2.4 children per family) which would sustain the current world population numbers. But what about the "immortality dreams" of the future (i.e., nano-mechanisms that can enter cells and turn back the aging process). Right now, an expected lifespan is about 3 to 3.5 generations long and that is increasing. What happens when we increase that lifespan to 6 or more generations through improved medical technology? At some point the ZPG number will drop below 1.0 due to life expectancy itself. Unless something catestrophic happens (war or disease) the increase will continue.

Short term, this world needs to focus on renewable resources, including products from our farmlands, but this won't stop or control our population growth. The only long term answer to controlling the population on earth (that isn't inhumane) is to access new resources by populating other planets.