@djc ethically, or really practically, it’s just that price discrimination is problematic. we pay people for the goods they provide, not for an interaction of the goods they provide and how easy or hard it is for them to provide it. it’s not a good idea to arrange society around charging or paying people different prices for goods based on capacity to pay or deliver. they are providing the goods, we should pay them the price. 1/

@djc (“sliding scale” payment sounds progressive, but it’s mostly bad way to arrange things, outside of some very special cases where it’s used for goods that essentially everyone purchases. college tuition on a sliding scale, for example, sounds good, but why should rich parents of college students fund the education of poorer college kids more than members of the general piblic should?) 2/

@djc just like we would and should object to Amazon following around our web activity and deciding we can afford it so offering us worse prices for exactly the same good (“so we can charge less to others!” they would say), we should object to the state deciding some families are rich enough so we should pay them less for the good of quality childrearing. 3/

@djc at a practical level, deciding who will deliver quality child rearing without the state buying it is informationally and bureaucratically hard. you have all the usual baggage of application processes that often exclude the people you most want to target, because application requires social resources the rich more easily hold. you have the deadweight costs of the bureaucracy you stand up and other people must lose time to. 4/

@djc and you still won’t do a great job. states can’t do a great job. adjudicating tradeoffs based on fine-grained very local information is precisely what states are bad at, the sphere where we want to minimize the degree of state involvement. an application form can force you to guesstimate your forward income (creating deadweight potential perjury risks if you misestimate too badly). it will never know that your father-in-law is ill and you send thousands of dollars to help. 5/

@djc means tests are very costly ways of generating very low quality information even on their own terms of burden measurement. on purely practical grounds, they aren’t worth the trouble. when we impose a progressive income tax, we don’t and don’t have to pretend we are taking holistic circumstance into acount like benefits means tests do. the tax is a blunt imposition, sure maybe based around ethical conjectures like “equivalent sacrifice” but not expected to be just in a fine-grained way. 6/

@djc means tests are expected to be just in a fine-grained way, but cannot succeed. or if they are not, they cannot justify the costs — to the state and to applicants — of a standalone test when a crude means test already exists in the tax system. /fin