What is "human life" and what is not?

Overpopulation is always an issue; two kind of mostly culturally influenced behaviour we can observe: to beget children without thinking on a quality level of life, and cultures where people consider, for how many children can they ensure qualitatively good life.

The question is what a fulfilled human life is, and what is not. From a spiritual/religious point of view, and of course for every human being visible, “material” point of view. With “material” I mean also education and knowledge, which are not so extremely important from a religious perspective.

Should a man-made or artificial population regulation be a basic law on earth, on an international level for example?

Best Regards!