Sam Gregg argues that while natural law doesn't mandate market economies, it does render key practices of capitalism just and key practices of socialism usually unjust.

Natural Law and the Economy: 

A Reply to Miller

by Samuel Gregg

Natural law does not demand capitalism, but we can deduce from natural law that some institutions that are key to market economies are normally just, while practices key to socialist arrangements are usually unjust.

In his reply to my Public Discourse piece on conservatives and capitalism, Robert T. Miller critiques my argument that conservatives need to articulate principled, as opposed to simply utilitarian, cases for capitalism. I thank Miller for his careful outline of where we agree and disagree as well as for his criticisms. But I also thank him because this is precisely the type of discussion that conservatives should have more often.

Let me begin by noting where I agree with Miller's observations. First, he maintains that "capitalism is consistent with Aristotelian-Thomistic moral premises, but it is not obligatory given those premises."

Obviously much depends on what we mean by "capitalism." Those arrangements often described as "crony capitalism," for example, systematically violate many prohibitions (such as the proscription of theft) articulated by natural law. But if "capitalism" means the particular set of activities and institutions affirmed (albeit with many qualifications) by, for instance, John Paul II's 1991 encyclical Centesimus Annus, then it is broadly consistent with natural law premises.

That said, I agree with Miller that capitalism is not obligatory given these premises-indeed, I have never claimed that it is. Natural law theory has always maintained that humans enjoy considerable creativity within the framework provided by natural law when determining many political and economic positions.

On many such matters, as Robert P. George observes, "A number of possible schemes-bearing different and often incommensurable costs and benefits, risks and advantages-are consistent with natural law." In many cases, the legislator cannot, on natural law grounds, identify political or economic arrangements that are uniquely correct. Yet he can identify several options that meet the test of right reason, even if some of the options may be incompatible with each other. This is the kind of activity of the practical intellect that Aquinas called determinatio.

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