First off, the medical reasons women take time off are protected by employment law in a variety of ways and most professional careers offer generous paid time off with FMLA protection on their careers. So the biological argument is specious. Note many fathers also get equivalent time off with the mom.

The specialization argument makes no sense. Why does it make sense for the mother to specialize for the family than the man? You made a large unexplained logical leap in that one that I don’t think is defensible.

The reason is economic and tradition at this point. Due to unfair compensation practice that rewards women less for the same work it makes more sense for her to not work. Tradition also compels a lot of couples in this direction. Both of these forces work to take women out of the work force.

The return to work force friction is very sad, and I honestly don’t understand it.

> Because biology. Mothers have to take time off work (to give birth), fathers don’t.

This is not true. Just google "woman gives birth at work" for many examples. https://www.newsweek.com/colorado-woman-gives-birth-car-deal...

Also, in general, American workers tend to get fewer days off work than European workers, but it doesn't have to be that way.

Let's say a woman works 45 years during her life. That's well over 10,000 working days. And let's say she has 2 kids. How many days off do you think she needs, medically speaking, for childbirth? The percentage is very very low.

This is a very conservative view. Giving birth is something only the mother can do, but there is no biological reason why a mother should raise the child and not the father. This renders you argument about specialization mute. In almost every developed country, it's possible to work 32 hours instead of 40 hours, which means that with 3 days of daycare the mother and father can share the responsibility raising a child equally.

You misunderstood my argument.

If father specialises for work, he can devote 100%. If mother specialises for work, she can only devote 90% (or whatever, to account for birth & recovery in first year).

Therefore all things being equal (i.e. “controlling for other variables” in statistics) father specialising for work will be more profitable for the family than mother specialising for work. Everyone (well, every couple) is free to choose what they want, weighing tradeoffs along many dimensions (money isn’t everything, but it’s a lot) but don’t be surprised if choices are biased towards “economically sensible”.

Sure, you can also do things “equally” but I estimate you’ll be getting less, on average (i.e. you will earn less per day working 3x per week than 5x (or 6x))

So if I understand correctly, you are saying there are two scenarios:

1. Father working full-time, mother staying-at-home for a few years

2. Father and mother working both reduced hours

Your conclusion is that sum of wages accumulated over the career length of both the father and the mother is higher in scenario 1 than in scenario 2?

If that's the case, then first of all I doubt that's true. And second, that means we as a society are sacrificing gender equality in return for disposable income. I think gender equality is not worth a small increase in disposable income (and I don't even think that staying at home economically is the better choice).

No, I’m saying that (1) for most unequal splits, father working will be more profitable than mother working, because of biology (mother has to take time off), and (2) unequal splits are better than equal splits (e.g. both working 100%, or both working 60%) because the latter have negative externalities (childcare cost, kids raised by strangers, less career progress because only working 60% etc).

Some people will still take equal splits, but not all will.

> I think gender equality is not worth a small increase in disposable income

Not gonna respond to this part because I can’t really figure out what you meant, but one comment is: “gain for society, loss for individual” usually requires a fair amount of coercion.

Indeed you are right that "gain for society, loss for individual" requires coercion, so that's why equal splits should be more profitable (if it's not the case already). That's a political decision.

It’s the ideological difference between “equality” (of opportunity) vs “equity” (of outcome). The former increases freedom, the latter increases coercion.

I see freedom valuable and coercion damaging. Freedom to choose also requires you to be able to choose the “wrong” choice. So in my view enforcing gender equality is just as bad, if not worse, as enforcing gender inequality.

I'm not convinced working mothers are all that happier tbh, and by having them work the market equilibria shift towards requiring them to work. It's more like gain in individual freedom, loss for everyone.

Why wouldn't working mothers be happier? Are working fathers unhappier? I think people who have freedom of choice without facing pressure from society are happier. If they choose to stay at home in a level playing field, that's perfect. Everyone should make their own choice. But as long as the ratio between stay-at-home mothers and stay-at-home fathers is not 50/50, I believe mothers face more pressure from society than fathers and have less freedom of choice.

I also think your statement that more individual freedom for women is a loss for everyone needs some clarification. That's a wild thing to say. I hope I interpreted this wrong?

Most people don’t have the freedom to choose not to work.

> there is no biological reason why a mother should raise the child and not the father.

Breastfeeding in the early year(s) is a defensible reason I think.