Among classical liberals and libertarians there has been a pretty vehement debate about whether liberty is best shown to be of primary value in society via utilitarian or practical or by means of normative arguments. Utilitarian arguments work mostly with historical evidence: free institutions, markets, legal systems and such have been productive of much happiness or value in the past and this is why we should embrace them now and in the future. Every proposal for limiting liberty needs to be tested against the history of similar proposals of the past; the most persuasive way to show that liberty is of the highest importance in human community life is to keep producing comparative studies that show this. Those stressing the normative case do not disparage the utilitarian’s contribution to an understanding of freedom but claim that it isn’t decisive since there is always the response that the next time, perhaps, a bit of interference, rights-violation, bullying, nudging, etc., might work and it isn’t possible for these (historical, empirical) studies to show otherwise. On those occasions when there is doubt about the efficacy of free institutions, something else needs to be tried; after all, no one can prove that the principle of liberty–natural rights, etc.–is true (by empirical methods). Yet, the normative defender of the free system can argue, first, that over the pretty long span of human history, including, especially, regarding how best to manage scarce resources, the principles of the free market have proven to be superior to alternative principles (e.g., fascism, welfare statism, socialism, communitarianism). Second, when we consider a system of public policies or a constitution, we need to think in terms of principles, not scattered programs. And, third, it’s demonstrable that as political economic systems stack up against each other, those promoting human liberty are more respectful toward people than the alternatives. Finally, as a fifth consideration and a most important one from a normative perspective, without liberty there can be no morality or ethics; only free men and women are in a position to make significant moral decisions, of their own free will. And the debate goes on.