The principle that every individual on the planet is entitled to an equally valuable share of Earth’s natural resources has attracted support from a broad spectrum of political theorists, and increasinly so in the context of climate change, wherein the possession and use of natural resources is pivotal. Yet the Principle of Natural Resource Equality is not without its own problems. This article focuses on the problem of valuation. Unless and until its advocates are able to develop an adequate theoretical mechanism for determining the comparative value of two or more bundles of natural resources the principle lacks applicability and persuasive force. Three adequacy constraints on such a mechanism are presented (cultural, formal, and substantive) and then applied to a theorisation of the Principle of Natural Resource Equality that I have already expounded elsewhere, Global Equality of Resources. In each case I try to argue that Global Equality of Resources could satisfy the adequacy constraint, provided that both this theory and the relevant constraint are properly understood.
