Last week, I argued at Libertarianism.org that the Non-Aggression Principle has unacceptable implications for the issue of pollution.

This week, I adduce five more reasons why libertarians should reject the Non-Aggression Principle.

The basic problem with the NAP is its absolutist and single-minded focus on aggression as the defining issue of political morality.

It is, of course, common sense to think that aggression is a bad thing. But it is far from common sense to think that its badness is absolute, such that the wrongness of aggression always trumps any other possible consideration of justice or political morality. There is a vast difference between a strong but defeasible presumption against the justice of aggression, and an absolute, universal prohibition. As Bryan Caplan has said, if you can’t think of counterexamples to the latter, you’re not trying hard enough. But I’m here to help.

If aggression is absolutely wrong, then all pollution must be prohibited, no matter what the cost. If the prohibition of aggression is the only matter with which our theories of justice are concerned, then deliberately starving one’s child to death is no injustice (but trespassing across another person’s lawn to feed their starving child is).

Of course, there’s much more to be said about each of the issues I raise in the essay. It’s a blog post, and it would take a series of essays to do each of these subjects justice.

And I have no doubt that, given sufficient time, [libertarians] can think up a host of ways to tweak, tinker, and contextualize the NAP in a way that makes some progress in dealing with the problems I have raised in this essay. But there comes a point where adding another layer of epicycles to one’s theory seems no longer to be the best way to proceed. There comes a point where what you need is not another refinement to the definition of “aggression” but a radical paradigm shift in which we put aside the idea that non-aggression is the sole, immovable center of the moral universe. Libertarianism needs its own Copernican Revolution.