@djc sure we should ask. generally we provide benefits to fund positive externalities (eg schooling), and as social insurance against hardship (eg health benefits). child benefits are a bit of both, quality childrearing has positive externalities we want to finance and childrearing imposes costs we want to mitigate. 1/

@djc when mitigating costs, we have to worry about moral hazard, we can’t just say the benefit should scale with the costs to the degree people might cause the costs in undesirable ways (so we don’t provide a cash benefit for heroin users, even though the habit is burdensome and costly, while we should pay for opiates for cancer patients). 2/

@djc with positive externalities, it’s not problematic to scale the benefit with the value. (although of course the public wants some surplus too, we shouldn’t pass as benefits the full value of the positive externalities if the provider of the externalities doesn’t require that. parents often do enjoy their kids!) so all else equal, the generosity of the maximum benefit we should be willing to provide (though again, we might provide less) should depend on the net value of the externality. 3/

@djc how much with child-rearing that depends on housing scarcity i think is arguable. regardless of how expensively and unpleasantly we are housed (when we ought to have abundant housing), we will need people to provide goods and services when living generations are old. and much (most i think) of the externalities we pay for with a child benefit has to do with quality of upbringing rather than quantity of kids. 4/

@djc there’s some relationship between natality and benefits generosity, but it’s not super strong. countries that want to increase their birth rates have to offer very, very generous benefits to make a small dent, is my understanding. but given whatever number of kids will come to exist, having them being raised with good nutrition and stable shelter etc, rendering them capable of interacting well with education benefits we also fund, has strong positive externalities for the rest of society.5/

@djc we need capable, responsible, healthy, not embittered cocitizens and future producers regardless of how many they are. so i don’t think the case for a generous child benefit interacts so strongly with housing, even though in principle it could (if the quantity dimension were more important than quality, and the external benefit net of costs imposed of additional humans is very sensitive to housing arrangements). /fin