The paper reaffirms the author's view that entropy is not relevant to the economics of natural resource scarcity. Once system boundaries are carefully defined, entropic considerations are either already incorporated into relative price information or represent such a long-run constraint as to be irrelevant to foreseeable human welfare. While matter and energy both undergo entropic dissipation, it is argued there is an asymmetry in that energy can be imported to recycle matter, but the converse, importing matter to recycle energy, is pure science fiction. Therefore, an open system, such as the earth, can maintain any level of organization. (C) 1994 Academic Press, Inc.