 Standard welfare economics does not make interpersonal comparisons because it asks whether policies constitute a Pareto improvement over the status quo. A policy constitutes a Pareto improvement if and only if it makes some people better off while making no-one worse off. But few policies are as unequivocal as this standard demands. Especially when it comes to the items that are usually discussed under the rubric of public goods, it is rarely if ever the case that no-one is made worse off by the provision.