Population control

[AFTT47]

Yup, probs v tricky to implement but essential IMO to the survival of the species.

Actually -

Implementing a mandatory restriction would be horrible way to go. (Like China tried)

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We need to change the mindset. We need to get people to WANT to not procreate. We need to quit rewarding breeders with tax advantages. We need to change our beliefs. 

Yes, like so many other things that ail society, this one can best be cured by a culture shift. A good start would be an acceptance of people who chose not to procreate. I suspect that there are many more people than you think who really don't want children but ultimately give in to social pressures. They are made to feel selfish, weird, even a guilt complex by not procreating. It's the same thing with marriage.

People have to understand and accept that marriage and children are not for everybody. I think such a cultural shift by itself would result in substantially lower birth rates. Lets take the stigma off childless and single people. In fact, lets turn it around and stigmatize the people putting the pressure on others to submit to a lifestyle which doesn't suit them. Who benefits from reluctant parents?