on the world's population. If we let Nature, i.e. loss of petroleum, take its course, a decline of 6 percent would result in a drop in world population to half its present level, i.e. to 3.5 billion, by about the year 2020, a mere decade from now. The only means, however, would be a rather grim one: famine. On the other hand, a deliberate global campaign of RPD, even with the immediate implementation of an utterly hypothetical fertility rate of zero (i.e. the implementation of a "zero-child policy"), would be far less dramatic. The rate of population decline would exactly equal the death rate. (This is true by definition: "growth rate" equals "birth rate" minus "death rate", and we have already said "birth rate" is zero.) The present death rate is about 1 percent (CIA, 2010). At that rate, the global population in the year 2020 would still be about 6.3 billion. There would therefore be no means for such a program of RPD to work before the effects of fossil-fuel depletion took their own toll. drjohn : 23 Dec 2010 2:15:39pm Over-population is the pre-eminent problem in our modern world. It underlies most other environmental issues. I'm sure that the population debate in Australia will be clouded by the immigration and refugee debates while in fact it does not have to be about either of these. A ZPG policy and a multicultural, humane society are not mutually exclusive concepts. Australia has an opportunity to maintain a stable population but,