I defend the view that supervenience relations need not be explained. My view is that some supervenience relations are brute, and explanatorily ultimate. I examine an argument of Terrence Horgan and Mark Timmons. They aim to rehabilitate John Mackie’s metaphysical queerness argument. But the explanations of supervenience that Horgan and Timmons demand are semantic explanations. I criticize their attempt to explain psychophysical supervenience in this fashion. I then turn to their ‘Twin Earth’ argument against naturalist (...) moral realism. I reconstruct their argument in a charitable spirit. But then I show that the argument mutates into an epistemological argument. That is where the real problems for moral realism lie. (shrink)

I defend the view that supervenience relations need not be explained. My view is that some supervenience relations are brute, and explanatorily ultimate. I examine an argument of Terrence Horgan and Mark Timmons. They aim to rehabilitate John Mackie’s metaphysical queerness argument. But the explanations of supervenience that Horgan and Timmons demand are semantic explanations. I criticize their attempt to explain psychophysical supervenience in this fashion. I then turn to their ‘Twin Earth’ argument against naturalist (...) moral realism. I reconstruct their argument in a charitable spirit. But then I show that the argument mutates into an epistemological argument. That is where the real problems for moral realism lie. (shrink)

I defend the view that supervenience relations need not be explained. My view is that some supervenience relations are brute, and explanatorily ultimate. I examine an argument of Terrence Horgan and Mark Timmons. They aim to rehabilitate John Mackie’s metaphysical queerness argument. But the explanations of supervenience that Horgan and Timmons demand are semantic explanations. I criticize their attempt to explain psychophysical supervenience in this fashion. I then turn to their ‘Twin Earth’ argument against naturalist (...) moral realism. I reconstruct their argument in a charitable spirit. But then I show that the argument mutates into an epistemological argument. That is where the real problems for moral realism lie. (shrink)

Part 1: Metaphysics and Conceptual Analysis 1. Analysis, description and the a priori?, Simon Blackburn 2. Physicalism, conceptual analysis and acts of faith, Jennifer Hornsby 3. Serious metaphysics: Frank Jackson’s defense of conceptual analysis, William G. Lycan 4. Jackson’s classical model of meaning, Laura Schroeter & John Bigelow 5. The semantic foundations of metaphysics, Huw Price 6. The folk theory of colours and the causes of colour experience, Peter Menzies Part 2: The Knowledge Argument 7. Consciousness and the frustrations of (...) physicalism, Philip Pettit 8. Jackson’s change of mind: representationalism, a priorism and the knowledge argument, Robert Van Gulick Part 3: Ethics 9. Analytic moral functionalism meets moral twin earth, Terrence Horgan & Mark Timmons 10. Consequentialism and the nearest and dearest objection, Michael Smith 11. The ’actual’ in actualism, Julia Driver Part 4: Conditionals and the Purposes of Arguing 12. Conditionals, truth and assertion, Dorothy Edgington 13. Conditionals: A debate with Jackson, Graham Priest 14. Two purposes of arguing and two epistemic projects, Martin Davies Replies to my critics, Frank Jackson. (shrink)

In recent years, with the appearance of a new wave of realism and non-descriptivism, the old dispute in meta-ethics between cognitivism and non-cognitivism has resurfaced. At present one of the most intensely discussed arguments among meta-ethicists is the so-called Moral Twin Earth argument of Terrence Horgan and Mark Timmons. It was presented in a series of articles published at the beginning of the nineties. However, a similar argument was put forth much earlier by Richard Hare, though the (...) participants of the discussion that has arisen in connection with the Moral Twin Earth have passed over it in silence. It appeared for the first time at the beginning of the fifties in The Language of Morals as the Missionary and the Cannibal Islands argument. Hare later renamed it the Reductio ad Absurdum of Descriptivism in an article published in 1986 under the same name. Since then he has made it as his basic instrument against descriptivism. In the present article the author outlines the argument of Moral Twin Earth, presents its prototype, and offers a concise criticism of it. (shrink)