First, we know that the mitigated skeptics had already come to see their method of arguing for and against ethical theses as a way of teaching ethics that allowed students to evaluate which views were more persuasive, i.e. had better rational grounds.
The dual theme of these works involved both a descriptive interpretation of the perversity, malice and imperfectability of human nature, as well as an ontological or meta-ethical thesis about the need for a non-natural, that is, religious or rational-intuitionist basis and source for moral imperatives in human society and history.
The discussion just completed, however, suggests reason to worry about this approach: there is not one ethical supervenience thesis but instead a complex variety of such theses.
This pattern can be captured by a general ethical supervenience thesis such as Initial (compare McPherson 2012, 211).
Indeed, if we understand Ascriptive as a conceptual claim, then together with realism it could provide the basis for accepting a conceptual-strength ethical supervenience thesis.
Nicolas Sturgeon suggests that one conclusion to draw from these difficulties is that there is no dialectically significant ethical supervenience thesis.
Supervenience is a modal claim, so contingent ethical nihilism the thesis that there are no actually instantiated ethical properties cannot explain ethical supervenience.
This case provides us with a specific ethical supervenience thesis: it suggests that the ethical quality of the manager's action cannot vary without something else varying as well (compare Horgan and Timmons 1992, 226 on specific supervenience facts).
Frank Jackson has argued that this allows us to state an ethical supervenience thesis: there is no possible difference that can be stated using evaluative predicates between states that are identical with respect to all properties picked out by descriptive predicates (1998, 118 125).
However, there are many distinct ethical supervenience theses that philosophers might be interested in.
Because stronger ethical supervenience theses are potentially both more illuminating and more dialectically significant, this section will focus on examining competing cases concerning what the strongest well-supported ethical supervenience thesis is.
