Caplan admits there are degrees of libertarian purity, as scored on his libertarian purity test. But of course there is more than one dimension of libertarian purity; in fact there are at least two dozen free variables in libertarian ethical theory.
Those free variables help explain why it takes a scorecard to keep track of the major schools of libertarianism. Hanson himself proposed in 1997 to use “Econ-Libertarian” to describe libertarians like him who “seek institutions whose consequences make most everyone better off according to their own estimation”. The Libertarian Party Platform Committee has worked over the last few years to make the platform more ecumenical to various kinds of libertarians, but we’re not done yet.
Matt, I agree on the question of objective morality. Your point about threats of violence can be applied to any form of “property”. Hanson’s argument is that ideas are indeed prosperity generators because of their positive externalities, and so he favors any institutional arrangements that will maximize those positive externalities. He sees prosperity as his trump card, not yours.
