Yeah, you're strawmanning or misreading what I was saying about the role of pareto optimality. I never said or implied that that principle is the totality of neoliberalism, nor did I say or imply that libertarians or neoclassicals use only pareto efficiency in their reasoning. That would be idiotic. No, I spoke, rather, of this being a "tool in their arsenal," and of how pareto optimality might "help" us distinguish between unjust and just redistributions of wealth. "Help," as in being just a factor in the assessment.
But let's leave all that aside, because what interests me is what the essence of pareto optimality is supposed to be. If this principle has some anti-libertarian outcomes, as you suggest, while it's also consistent with some libertarian policies, then it's possible this principle is just straight-up vacuous or vague. That, in turn, would support the charge that economics is a bogus science. In short, there may be only a very fine line between semantic emptiness and being "an incredibly weak" concept.
Unfortunately, you didn't engage with my attempt to put pareto optimality in ordinary, straightforward terms. Pareto's optimality principle seems closely related to Mill's harm principle. Harming someone is off the table because we should all make good on our freedom. What, then, does Pareto add to the basic moral rule against harming someone (in the economic context by taking their private property)? That is, morality in general says we shouldn't make anyone worse off (except maybe in self-defense). What does Pareto add to that moral principle?
Pareto says the best outcome is one in which it can't be improved without harming someone. Is that the gist of it? And by "harming" someone or making the person "worse off," is that supposed to be only a quantitative point about the subtraction of wealth or goods?
Suppose an evil monster steals everyone's stuff. Would Pareto say the best option is to find a way to improve everyone's impoverished state without taking the monster's stolen goods because doing the latter would technically harm the monster or make him worse off? That is, does Pareto's optimality principle abstract entirely from the law, from morality, and from history, to focus only on the physical act of taking stuff from X to give it to Y?
I'm asking in all honesty. I'd like to know how the principle is generally used in economics. Citing examples, though, doesn't help because the economic discourse is presumably impenetrable. Instead, I'd like to cut to the chase by getting at the principle's essence. Can you state the gist of the principle?