Every 5th grade science fair entrant knows that you make a hypothesis, and then you either prove or disprove the hypothesis with data (facts)
Of all the crazy hypotheses that have magically gone from conjecture to fact without ever having gone through the fact stage, perhaps the dumbest of all is the hypothesis that people "had children, up until our modern age, to help with farm work."
You see that statement everywhere! Everyone used to have kids to help on the farm, and that's why they had so many kids, because they needed a lot of help farming.
Now, it is perfectly okay to HYPOTHESIZE aloud "I bet one of the motivations for people to have kids was to help farm"
But to say that we KNOW that's why people had kids up until "modernity"is because of farmwork....that's simply conjecture masquerading as fact.
Do we have ANY evidence of this?
Have we unearthed a diary from anyone over the past 4,000 years suggesting that the hypothesis has any merit?
Dear diary, me and Helga are really trying to conceive a child so that 8-10 years from now, we'll have a cow milker!
Not only do we not have any evidence that would suggest that people had kids to help with farm work, I think it is also worth questioning the conjecture itself. Was the hypothesis put forward by anyone who has actually worked WITH a kid doing farmwork? I remember the productivity of my brothers and I working and "helping" in my Dad's garden, and I am sure that our "help" fell into the category of "Dad probably being better off without the help"
So Helga and Jedidiah were willing to risk the mortality rate for mother AND child in child birth, then feed a "useless" mouth for 6-8 years, to risk and put forward all that in order for the CHANCE to get a teenager, 10 years later, who could help milk the cows?
It seems that to me, rather, that in order to justify our own society being the coldest bunch of utilitarians the world has ever known, we have to also project our frigid utilitarianism on everyone that came before us as well.
So, to make ourselves feel better, our child-farming hypothesis needs to very quickly become not a hypothesis but a fact. I KNOW that farming is why everyone had kids for the first 4,000 years of civilization.
Maybe, just maybe, though, at least some people for the first 4,000 years (and maybe even most people) just loved each other as husband and wife, and were open to their marital love begetting children despite the risk of giving birth.
Maybe, just maybe, some of the people who predate modernity didn't just sit around and coldly calculate how many children it would take to produce X gallons of milk per week and then set out to make love according to that calculus.
Maybe they DIDN'T do it that way, even if people today would