Horgan & Timmons

Illuminating Reasons: An Essay in Moral Phenomenology (Download PDF)

The following series of articles are critical of various forms of what we call "new wave moral realism." In many of these papers, we employ a form of argument, The Moral Twin Earth Argument named, of course, after Putnam's famous Twin Earth thought experiment.

Troubles on Moral Twin Earth: Moral Queerness Revived
Synthese 92 (1992): 221-260.

Troubles for New Wave Moral Semantics: The 'Open Question Argument' Revived
Philosophical Papers XXI (1992): 153-175.

From Moral Realism to Moral Relativism in One Easy Step
Critica XXVIII (1996): 3-39.

Copping Out on Moral Twin Earth
Synthese 124 (2000): 139-152.
This paper is a reply to David Copp's, 'Milk, Honey, and the Good Life on Moral Twin Earth', Synthese 124 (2000): 113-137.

Analytical Moral Functionalism Meets Moral Twin Earth
In Essays on the Philosophy of Frank Jackson, I. Ravenscroft, (Ed.), Oxford: Blackwell Publishers (2009): 221-230.
The basic moral twin earth recipe, modified mutatis mutandis to fit
Jackson's version of moral realism.

Twin Earth, Moral
In The International Encyclopedia of Ethics, H. LaFollett (Ed.), Oxford: Blackwell Publishing Ltd. (2013) 5242-5249.
An overview and bibliography of work on the MTE argument.

Exploring Intuitions on Moral Twin Earth: A Reply to Sonderhom
With Terry Horgan, Theoria 1-21 (2015). A reply to Jorn Sonderholm's article that was published in Theoria.  

Related Work:

The Limits of Moral Constructivism
(Timmons solo)
Ratio 16 (2003). Forthcoming. Special issue on T. M. Scanlon's, What We Owe to Each Other, P. Stratton-Lake (Ed.). Blackwell Publishers.
Moral Twin Earth makes an appearance.

Troubles for Michael Smith's Metaethical Rationalism
Philosophical Papers XXV (1996): 203-231.
We don't consider Smith's view as elaborated in his The Moral Problem a version of moral realism, and we don't use the Moral Twin Earth scenario in our critique of his view. Nevertheless, our work in this paper is in the same spirit as our work in the Moral Twin Earth papers.

On the Epistemic Status of Moral Judgments
(Timmons solo)
Southern Journal of Philosophy XXIX, Supplementary volume on Moral Epistemology (1990): 97-129.

This was authored by me, but was written after the Moral Twin Earth paper that Terry and I eventually published in Synthese.