[pmichaud]

The real answer about why people in general have children isn’t formatted like a “reason.” There’s a primal drive in most people, a kind of psychosomatic/biological imperative that drives them (to great lengths, when necessary) to have kids. That’s the real answer, and none of what you listed in the OP, including the maybe kind of true things, are a crux for that imperative.

[frontman1988]

The primal drive is only of sex. Most people throughout history wanted sex, not babies. But now with birth control people have the choice. It's the reason why the fertility rate is declining in most developed countries. I think if birth control existed in the time of Jesus, then also a large majority of people would have chosen to be childfree or have only 1-2 kids

[pmichaud]

I think sex is a tightly related primal drive, but no, I think literally children is something similar, mostly for slightly older people, mostly women, but with plenty of young people and men feeling it too. I know a lot of people like this, it seems to come in a wave at a certain life stage.

[dementiapatien]

>The primal drive is only of sex.

What about people who turn down sex when they know the other party can't have kids?

[agent008t]

Is there a primal drive in most people though? I do not think any of my friends in high school or in college had any great longing of becoming a father - did you? They had plenty of other drives, though. So if this primal drive you speak of exists, it must somehow appear out of seemingly nowhere - indeed out of aversion - after one's mid 20. And the mechanism for that eludes me. What sort of hormonal changes lead to it? Is it a gradual change, or do you wake up one morning and think 'God, you know what I'd really love? To be looking after a baby!'

[sforza]

Indeed. We all know that what really happens is the majority of women want children and their men simply go along with it.

[pmichaud]

I do think it's related to age, and appears "out of nowhere." A lot of people describe it as "waking up one morning, and..." I don't know the mechanism, but sure, it might be hormonal.