What is the rational case for having children?
One can tell a story about how evolution made us not simply to enjoy the act that causes children but to want to have children. But that's not a reason, that's a description of the desire.
One could tell a story about having children as a source of future support or cost-controlled labor (i.e. farmhands). But I think the evidence is pretty strong that children are not wealth-maximizing in the modern era.
And if there is no case for having children, shouldn't that bother us on "Our morality should add up to normal, ceteris parabis" grounds?
Rationality helps you map out the relations between actions and goals, and between goals and subgoals; and it can help us better understand the structure of the goals we already have. We can say that doing something is good because it helps achieve goals, or bad because it hinders them; and we can say that certain things are also goals (subgoals), if achieving them helps with our original goals. However, this has to bottom out somewhere; and we call the places where it bottoms out - goals that're valued in and of themselves, not just because they help with...
If it's worth saying, but not worth its own post (even in Discussion), then it goes here.
(I plan to make these threads from now on. Downvote if you disapprove. If I miss one, feel free to do it yourself.)