The way I think isn't "people shouldn't don't have kids", it's "don't force yourself to have kids if you don't want them, and don't expect kids to be the path to solving your own problems -- they may, in fact, just magnify every problem you have". I'm fairly certain that even everyone agreeing with that wouldn't lead to the extinction of the species, but it may lead to less children being raised in dire or abusive circumstances, and less parents miserable with their own existence.

I agree that this way of thinking probably runs contrary to the evolutionary code of the species. But we live in a world where that code is outdated, and education should allow us to teach people that marriage and child-rearing, while the right path for many people, is not the only route to self fulfillment and happiness. And those that choose alternate paths should not be treated as, or feel like, outcasts.

I agree