… is from page 442 of the late University of Washington economist Paul Heyne ‘s profound 1993 article “Economics, Ethics, and Ecology ,” as this article is reprinted in the 2008 collection of Heyne’s writings, “Are Economists Basically Immoral?” and Other Essays on Economics, Ethics, and Religion  (Geoffrey Brennan and A.M.C. Waterman, eds.) (original emphasis):
Of course, there is no ultimate foundation for ethical or value judgments that everyone is compelled to accept. But there is no ultimate foundation that everyone must accept for any other kind of proposition, either, including the propositions put forward in the name of science. That is the fatal flaw in the other half of economists’ traditional argument against mixing economics and ethics. Economic research always employs presuppositions, and some of these presuppositions will almost inevitably have ethical implications. Those who claim to be engaging in value-free economic analysis are simply unaware of all the subtle ways in which values influence economic inquiry.