With regard to why people elect to have children, the theoretical explanation often goes to "providing security for old age." The basic concept is that children represent a kind of investment or insurance that parents can collect in old age.
在理論上，關於人們生養小孩的選擇，一種常見的解釋是「養兒防老」，亦即父母將現在的收入以「生小孩」的形式儲存起來，並寄望這些「小孩」日後會奉養他，類似於把孩子當作一種「投資財」（或保險）。