MOJ: "Much Ado About Subsidiarity" (which links to this post at VN, which notably does not offer a definition of the common good, but one assumes that the one current in CST is implied). Garnett cites Russell Hittinger for an explanation of subsidiarity, and Hittinger adequately presents contemporary teaching on the concept. What is missing, to circumscribe the definition of subsidiarity and the state? A notion of the common good (life in community) that is tied to an understanding of the proper human scale.

If the common goods that exist at different "levels" do not have the same definition, then how can there be an ordered hierarchy of authorities serving them? If common good1 is not a part of common good 2, then how can authority1 be subordinate to authority2? An authority that serves to preserve the peace of many communities cannot have any sort of authority over the communities themselves - this would go beyond its competence.