Michael Huemer, The Problem of Political Authority , p. 177:
> Libertarian political philosophy rests on three broad ideas:
> (1) A nonaggression principle in interpersonal ethics. Roughly, this is the idea that individuals should not attack, kill, steal from, or defraud one another and, in general, that individuals should not coerce one another, apart from a few special circumstances.
> (2) A recognition of the coercive nature of government. When the state promulgates a law, the law is generally backed up by a threat of punishment, which is supported by credible threats of physical force directed against those who would disobey the state.
> (3) A skepticism of political authority. The upshot of this skepticism is, roughly, that the state may not do what it would be wrong for any nongovernmental person or organization to do.
There is a kind of deontology called "Moderate Deontology", which says there are moral rules, but that these rules can be overridden in case of extreme consequences. This is in contrast to other forms of deontology, which may not consider consequences at all. This is a highly intuitive normative theory because in common sense morality, both rights and consequences seem morally important. There are obvious cases where the ends do not justify the means... unless the ends are severe enough, that is.
On this view, once you establish the 'rights' (like to property, and to not be stolen from), then their appeal to 'hospitals' is an appeal to an extreme negative consequence. You don't have to show that no-tax funded hospitals are better than tax funded ones. Only that a society without tax will sufficiently be able to provide health care to its general population -- in other words, that it wouldn't completely break down into a healthcare hellscape. Additionally, the burden of proof is on them to show that the consequences would be devastating (and usually they cannot bear that burden. Usually, they are highly ignorant about the specific topics at hand.)
Also, and I cannot stress them enough, appeal to moral premises they already accept, like that it would be wrong for non-governmental entities to steal money to provide [insert service here], and then challenge them to provide the morally relevant difference between a non-governmental agent and a governmental agent doing that thing. If they cannot provide that difference, then it is irrational for them to accept one while rejecting the other. (This argumentation strategy is employed by Michael Huemer in his book "The Problem of Political Authority" )
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