This paper presents two cases demonstrating that theories allowing the environment to partially determine the content of moral concepts (such as the causal theory of reference) that provide incorrect truth-conditions for moral terms. While typical Moral Twin Earth cases seek to establish that these theories fail to account formoral disagreement, neither case here essentially involves interpersonal disagreement. Both involve a single person retaining moral beliefs despite recognizing actual or potential mismatches with the purportedly content-determining facts. This lets opponents of such theories grant objections that standard Moral Twin Earth cases fail to demonstrate disagreement, and argue more straightforwardly that they generate implausible truth-conditions for moral claims.

Amid all his famously changeable views, Hilary Putnam held a long-standing commitment to semantic externalism about natural kind terms. Early on, Putnam claimed an affinity between this view and Saul Kripke’s work on natural kind terms as ‘rigid designators’. This led to many authors referring to the ‘Kripke-Putnam’ view of natural kind terms. Subsequently though, Putnam sought to distance his view from that of Kripke, particularly with regard to Kripke’s commitment to metaphysical necessity and essentialism – a commitment I regard as untenable in the face of actual scientific classification. I want to argue that rejecting these commitments of Kripke’s should have also forced Putnam to revise some of his most strongly held views. First, I will argue that externalism without essentialism cannot support Putnam’s own intuition about his Twin Earth thought experiment. Second, I will argue that Putnam loses a sufficiently general and univocal notion of ‘substance identity’ that was necessary for supporting his reading of the Twin Earth case and also for guaranteeing the reference of scientific terms across theory changes. First, I will argue that externalism without essentialism cannot support Putnam’s own intuition about his Twin Earth thought experiment. Second, I will argue that Putnam loses a sufficiently general and univocal notion of ‘substance identity’ that was necessary for supporting his reading of the Twin Earth case and also for guaranteeing the reference of scientific terms across theory changes. Similar content being viewed by others Semantic Analyses of Hilary Putnam’s Twin Earth (Ft. Subsequently though, Putnam sought to distance his view from that of Kripke, particularly with regard to Kripke’s commitment to metaphysical necessity and essentialism. I want to argue that rejecting these commitments of Kripke’s should have also forced Putnam to revise some of his most strongly held views. First, I will argue that externalism without essentialism cannot support Putnam’s own intuition about his Twin Earth thought experiment. Necessary, in that they are true in all metaphysically possible worlds. A posteriori, in that they were not analytic or a priori truths arrived at by considering the concepts of, say’ ‘water’ and ‘H 2 O’, but were instead the upshot of empirical investigation that showed the property of ‘being water’ to be identical with the property ‘being H 2 O’. Footnote 6 It is also common for this supposedly shared view to be illustrated via the famous Twin Earth thought experiment, which typically goes something like this. Start by considering Earth in the actual world. On Earth, the lakes, rivers and faucets are filled with stuff we English speakers on Earth call ‘water’. In Putnam’s original telling, me and my Twin Earth duplicate’s brain states and psychological states are identical, yet what our terms mean differs. Hence thesis (i), Semantic Externalism, is true, or, as Putnam famously put it, “‘meanings’ just ain’t in the head” ( 1975g , p. 227). Meanings are instead partly constituted by the environment in which a speaker is situated and the community of speakers to which they belong. The fact that my normal environment contains H 2 O and not XYZ makes it the case that my word ‘water’ refers only to the former stuff. In the following section, I will argue that some of these differences suggest that Putnam should have drawn different conclusions in the Twin Earth case from those he drew in “The Meaning of ‘Meaning’” and maintained for the rest of his life. What this shows more ( 1990a , 59) Putnam is clearer here, than in his earlier work, that this would be “the correct thing for the scientist” to say, although it may or may not be the obligatory thing to say for an unscientific layperson. As Putnam already pointed out in “The Meaning of Meaning”, there are different senses of the word ‘water’ used by laypeople. Any scientist, however, speaking as a scientist must have the rigid use of ‘water’ in mind and must be committed to the claim that Twin Earth ‘water’ turned out not to be water. Other things Putnam said seriously undermine this claim though. (Curiel unpublished , 9) Putnam, unlike Kripke, is interested in describing a physically possible future in the actual world. Mere metaphysical possibilities don’t make sense to Putnam aside from being ways we might want to use words that don’t cause confusion. But that means that Putnam’s initial reply to the Twin Earth thought experiment should simply have been ‘that is not physically possible by our current lights’. If we are being asked to entertain such a possibility, then we are entertaining a course of events in which our chemical and physical theories turn out to be badly wrong. But the presumed success of those theories is what makes microstructure a deep, important property! By Putnam’s own lights, it seems his own Twin Earth scenario represents a case where we would lose our (supposed) rationale for counting being H 2 O as the essential property of water. Does Twin Earth then demonstrate that we must say that ‘Twin-water is water’? Although I think there is some rationale by Putnam’s own lights for saying that rather than its opposite I myself favour a more agnostic view. Namely one along the lines of that articulated by Thomas Kuhn. Kuhn quotes part of the same passage from Austin in discussing what occurred with the term ‘mammal’ as the proper response to the question “What should one have said when confronted by an egg-laying creature that suckles its young?”. See ( 1990 , p. 306). Kuhn discusses the Twin Earth case later in that same paper, saying in response “Its discovery would present the same problems as the simultaneous violation of Newton’s second law and the law of gravity described in the last section. It would, that is, demonstrate the presence of fundamental errors in the chemical theory that gives meanings to compound names like ‘H 2 O’ and the unabbreviated form of XYZ’.” (310).

Twin-Earth Externalism Revisited Skoči na glavni sadržaj english Prijava i registracija Prijava Promjena načina autentikacije Registracija Croatian Journal of Philosophy , Vol. 25 No. 74 , 2025. Izvorni znanstveni članak https://doi.org/10.52685/cjp.25.74.9 Twin-Earth Externalism Revisited Simon Dierig ; Heidelberg University, Heidelberg, Germany Puni tekst: engleski pdf 177 Kb str. 221-236 preuzimanja: 212 citiraj APA 6th Edition Dierig, S. (2025). Twin-Earth Externalism Revisited. Croatian Journal of Philosophy, 25 (74), 221-236. https://doi.org/10.52685/cjp.25.74.9 MLA 8th Edition Dierig, Simon. "Twin-Earth Externalism Revisited." Croatian Journal of Philosophy , vol. 25, br. 74, 2025, str. 221-236. https://doi.org/10.52685/cjp.25.74.9. Citirano 08.08.2026. Chicago 17th Edition Dierig, Simon. "Twin-Earth Externalism Revisited." Croatian Journal of Philosophy 25, br. 74 (2025): 221-236. https://doi.org/10.52685/cjp.25.74.9 Harvard Dierig, S. (2025). 'Twin-Earth Externalism Revisited', Croatian Journal of Philosophy , 25(74), str. 221-236. https://doi.org/10.52685/cjp.25.74.9 Vancouver Dierig S. Twin-Earth Externalism Revisited. Croatian Journal of Philosophy [Internet]. 2025 [pristupljeno 08.08.2026.];25(74):221-236. https://doi.org/10.52685/cjp.25.74.9 IEEE S. Dierig, "Twin-Earth Externalism Revisited", Croatian Journal of Philosophy , vol.25, br. 74, str. 221-236, 2025. [Online]. https://doi.org/10.52685/cjp.25.74.9 Sažetak The aim of this article is twofold: First, it is argued that Tyler Burge’s case for externalism in the philosophy of mind, which is based on Hilary Putnam’s twin-earth thought experiment, fails. Second, it is shown that a convincing argument for externalism can be nonetheless construed by relying on Putnam’s thought experiment. Ključne riječi Externalism ; twin earth ; philosophy of mind ; beliefs ; Putnam ; Burge. Hrčak ID: 340284 URI https://hrcak.srce.hr/340284 Datum izdavanja: 1.12.2025. Posjeta: 514 *

A universal language spoken on Earth.: #: #* 1997. Diego Marconi. Lexical Competence. MIT Press: 1997, page 102: #*: According to Fodor's definition, it follows that 'water' in Twin Earthian means XYZ and not H2O. #* 2004. Sheri S. Tepper. The Companions. HarperCollins: 2004, page 79: #*: I thought the females spoke Earthian to you. Improving their Earthian was why they asked for a couple.

This essay reviews and examines the controversies surrounding Searle’s rebuttal sparked by Putnam’s Twin Earth experiment. The article firstly analyzes Putnam’s definition of natural kind terms and points out that there is a difference between natural kind terms and descriptivism, which cannot be explained in equal quantities. From the perspective of the Twin Earth experiment, understanding Putnam’s definition and interpretation of natural class terms can be the key to refuting Searle’s rebuttal, which can prove that the externalist stance of the Twin Earth experiment has not been severely undermined. On this basis, this article provides multiple examples to further explore and demonstrate that even with the use of index words that are consistent with Searle’s explanatory approach, the final conclusion is not contradictory to semantic externalism and can still point to the perspective of externalism. At the end of the article, the author attempts to achieve a more reasonable balance in semantic interpretation by explaining the connection between semantic internalist and externalist elements.

AbstractIt is argued that externalism about the contents of propositional attitudes is supported not only by examples and thought experiments, but also by an intuitively plausible theoretical account of intentionality: the idea that the contents of intentional mental states should be explained in terms of the information that those states are disposed to carry. The theoretical account helps to bring out what is paradoxical about the externalist's thought experiments, and to show why attributions of content are essentially context‐dependent.