A brief account of Putnam's Twin Earth thought experiment and its significance, written for a general audience. Sadly, I can't include Helen De Cruz's drawing of it - check out the beautiful book!

Healthcare is one of the domains in which artificial intelligence (AI) is already having a major impact. Of interest is the idea of the digital twin (DT), an AI-powered technology that generates a real-time representation of the patient’s body, offering the possibility of more personalised care. Our main thesis in this paper is that the DT does not merely represent the patient’s body but produces a specific body. We argue, from a philosophical perspective and an ethical-phenomenological approach, that the virtual (...) body created by the DT has a major impact on one’s self-understanding, having consequences for gender expression and identification, and for health. This has deep implications for people who do not conform to gender normativity, for example, trans individuals. We advocate that, with thoughtful development, DT technology can and should be empowering, contributing to better addressing the diversity of bodies and facilitating trans people’s experience in healthcare contexts. (shrink)

This article examines digital twins' applications and future directions in supply chain management. Digital twins, virtual representations of physical objects or processes, revolutionize supply chain operations by providing real-time insights and predictive capabilities. The global digital twin market is projected to reach $48.2 billion by 2026, driven by the need for real-time monitoring and predictive maintenance across industries. The article discusses the key components of supply chain digital twins, their implementation in the distribution industry, and their numerous benefits, including enhanced (...) visibility, improved forecasting, risk mitigation, and increased efficiency. Challenges such as data integration and skill shortages are also addressed. The article concludes by exploring future directions, including AI integration, IoT expansion, blockchain integration, extended reality interfaces, and cross industry collaboration, highlighting the transformative potential of digital twins in creating more resilient, agile, and intelligent supply networks. (shrink)

In this paper I argue against Twin-Earth externalism. The mistake that Twin Earth arguments rest on is the failure to appreciate the force of the following dilemma. Some features of things around us do matter for the purposes of conceptual classification, and others do not. The most plausible way to draw this distinction is to see whether a certain feature enters the cognitive perspective of the experiencing subject in relation to the kind in question or not. If it does, we (...) can trace conceptual differences to internal differences. If it doesn’t, we do not have a case of conceptual difference. Neither case supports Twin Earth externalism. (shrink)

Horgan and Timmons have argued that our intuitions about the semantics of non-moral language and moral language differ, and that while twin-earth semantic intuitions generate one result in Putnam´s twater case, moral twin-earth fails to generate comparable results for moral terms. Horgan and Timmon´s conclude from this that the semantic norms governing the use of natural kind terms differ from the semantic norms governing the use of moral terms. I will argue that Horgan and Timmons’ intuitive moral twin-earth argument fails (...) to derail the new moral realism. Further, I will discuss Boyd’s semantic theory and raise problems for it that do not rely on the use of moral twin-earth. (shrink)

Fetal reduction is the practice of reducing the number of fetuses in a multiple pregnancy, such as quadruplets, to a twin or singleton pregnancy. Use of assisted reproductive technologies increases the likelihood of multiple pregnancies, and many fetal reductions are done after in vitro fertilisation and embryo transfer, either because of social or health-related reasons. In this paper, I apply Joe Horton’s all or nothing problem to the ethics of fetal reduction in the case of a twin pregnancy. I argue (...) that in the case of a twin pregnancy, there are two intuitively plausible claims: abortion is morally permissible, and it is morally wrong to abort just one of the fetuses. But since we should choose morally permissible acts rather than impermissible ones, the two claims lead to another highly implausible claim: the woman ought to abort both fetuses rather than only one. Yet, this does not seem right. A plausible moral theory cannot advocate such a pro-death view. Or can it? I suggest ways to solve this problem and draw implications for each solution. There are no data in this work. (shrink)

Horgan and Timmons, with their Moral Twin Earth arguments, argue that the new moral realism falls prey to either objectionable relativism or referential indeterminacy. The Moral Twin Earth thought experiment on which the arguments are based relies in crucial ways on the use of intuitions. First, it builds on Putnam’s well-known Twin Earth example and the conclusions drawn from that about the meaning of kind names. Further, it relies on the intuition that were Earthers and Twin Earthers to meet, they (...) would be able to have genuine moral disagreements. I will argue that the similarities with Putnam’s thought experiment are questionable and so the reliance on Putnam-like intuitions is questionable. I will then further argue that even if we accept the intuitions that Horgan and Timmons rely on, the anti-realist conclusion is not warranted due to there being more to the meaning of kind terms than the argument assumes. Once we develop the meaning of kind terms further we can acknowledge both that Earthers and Twin Earthers refer to different properties with their moral terms, and that in spite of that they can have a substantive disagreement due to a shared meaning component. (shrink)

In special cases of partial twinning, two heads, each supporting a more-orless normal human mental life, emerge from a single torso. It is often argued that there must be two people in such a case, even if there is only one biological organism. That would pose a problem for ‘animalism’, the view that people are organisms. The paper argues that it is very hard to say what sort of non-organisms the people in such cases would be. Reflection on partial (...) twinning is no more comfortable for those who think we’re not organisms than for those who think we are. We may have to accept that a single person could have two separate mental lives. (shrink)

In this paper I revisit an important response to the Moral Twin Earth (MTE) challenge: The Common Functional Role strategy (CFR). I argue that CFR is open to a revenge problem. MTE-cases allegedly show that two linguistic communities can be in genuine disagreement even when they are regulated by distinct families of properties. CFR provides a way to reconcile the intuition that the two communities are in genuine disagreement with the claim that the use of moral terms by both communities (...) is causally regulated by different families of properties. This is done by identifying a functional role that those families of properties both fulfill. Still, even if CFR is successful, its proponents need to face a serious revenge problem. Roughly, it could be that the families of properties that regulate each community are equally perfect realizers of the relevant higher-order functional state. I suggest that the proponent of CFR faces a dilemma: either CFR has controversial implications about first-order moral theory, or CFR needs to be coupled with substantive and parochial empirical/metaphysical assumptions to avoid those implications. (shrink)

In this paper I develop an argument against applying a causal theory of mental content to normative concepts. This argument—which I call the Intrapersonal Normative Twin Earth Argument—is inspired by Terry Horgan and Mark Timmons’ Moral Twin Earth Argument. The focus of Horgan and Timmons’ argument is showing that causal theories of mental content conflict with plausible claims about interpersonal normative disagreement. The Intrapersonal Normative Twin Earth Argument, by contrast, is focused on showing that such theories struggle to vindicate plausible (...) claims concerning whether two of an agent’s token normative thoughts have the same or distinct content. (shrink)

Background: The concept of digital twins has great potential for transforming the existing health care system by making it more personalized. As a convergence of health care, artificial intelligence, and information and communication technologies, personalized health care services that are developed under the concept of digital twins raise a myriad of ethical issues. Although some of the ethical issues are known to researchers working on digital health and personalized medicine, currently, there is no comprehensive review that maps the major ethical (...) risks of digital twins for personalized health care services. Objective: This study aims to fill the research gap by identifying the major ethical risks of digital twins for personalized health care services. We first propose a working definition for digital twins for personalized health care services to facilitate future discussions on the ethical issues related to these emerging digital health services. We then develop a process-oriented ethical map to identify the major ethical risks in each of the different data processing phases. Methods: We resorted to the literature on eHealth, personalized medicine, precision medicine, and information engineering to identify potential issues and developed a process-oriented ethical map to structure the inquiry in a more systematic way. The ethical map allows us to see how each of the major ethical concerns emerges during the process of transforming raw data into valuable information. Developers of a digital twin for personalized health care service may use this map to identify ethical risks during the development stage in a more systematic way and can proactively address them. Results: This paper provides a working definition of digital twins for personalized health care services by identifying 3 features that distinguish the new application from other eHealth services. On the basis of the working definition, this paper further layouts 10 major operational problems and the corresponding ethical risks. Conclusions: It is challenging to address all the major ethical risks that a digital twin for a personalized health care service might encounter proactively without a conceptual map at hand. The process-oriented ethical map we propose here can assist the developers of digital twins for personalized health care services in analyzing ethical risks in a more systematic manner. (shrink)

This paper presents two cases demonstrating that theories allowing the environment to partially determine the content of moral concepts 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. (shrink)

It is widely believed that Twin-Earth-style thought experiments show that the contents of a person's thoughts fail to supervene on her intrinsic properties. Several recent philosophers have made the further claim that Twin-Earth-style thought experiments produce metaphysically necessary conditions for the possession of certain concepts. I argue that the latter view is false, and produce counterexamples to several proposed conditions. My thesis is of particular interest because it undermines some attempts to show that externalism is incompatible with privileged access.

In a recent paper in this journal, McCall and Lowe (2003) argue that an understanding of Special Relativity reveals that the A theorist’s notion of temporal passage is consistent with the B theory of time. They arrive at this conclusion by considering the twins’ paradox, where one of two twins (T) travels to Alpha Centauri and back and upon her return has aged 30 years, while her earth-bound twin (S) has aged 40 years.Does this reconcile the A theoretic notion of (...) temporal passage with the B theory of time? I argue not. (shrink)

Mark Timmons and Terry Horgan have argued that the new moral realism, which rests on the causal theory of reference, is untenable. While I do agree that the new moral realism is untenable, I do not think that Timmons and Horgan have succeeded in showing that it is. I will lay out the case for new moral realism and Horgan and Timmons’ argument against it, and then argue that their argument fails. Further, I will discuss Boyd’s semantic theory as well (...) as attempts to improve upon it, raise serious problems for these semantic accounts, and suggest an alternative view that accounts for our use of moral terms. (shrink)

Cognitive twins, digital replicas of cognitive processes, have emerged as a transformative approach in artificial intelligence and human-machine collaboration. This paper presents a framework for developing a cognitive twin by integrating a Distributed Cognitive System (DCS) with Evolutionary Strategies (ES). The DCS enables decentralized knowledge processing, while ES optimizes learning and adaptation over time. Our approach is evaluated on real-world datasets, demonstrating its efficiency in cognitive modeling and decision-making. Results highlight improvements in adaptability, scalability, and accuracy compared to traditional AI (...) models. (shrink)

The article examines the impact of the virtual public sphere on how urban spaces are experienced and conceived in our data-driven society. It places particular emphasis on urban scale digital twins, which are virtual replicas of cities that are used to simulate environments and develop scenarios in response to policy problems. The article also investigates the shift from the technical to the socio-technical perspective within the field of smart cities. Despite the aspirations of urban scale digital twins to enhance the (...) participation of citizens in the decision-making processes relayed to urban planning strategies, the fact that they are based on a limited set of variables and processes makes them problematic. The article aims to shed light on the tension between the real and the ideal at stake during this process of abstracting sets of variables and processes in the case of urban scale digital twins. (shrink)

Michael Scriven’s (1959) example of identical twins (who are said to be equal in fitness but unequal in their reproductive success) has been used by many philosophers of biology to discuss how fitness should be defined, how selection should be distinguished from drift, and how the environment in which a selection process occurs should be conceptualized. Here it is argued that evolutionary theory has no commitment, one way or the other, as to whether the twins are equally fit. This is (...) because the theory of natural selection is fundamentally about the fitnesses of traits, not the fitnesses of token individuals. A plausible philosophical thesis about supervenience entails that the twins are equally fit if they live in identical environments, but evolutionary biology is not committed to the thesis that the twins live in identical environments. Evolutionary theory is right to focus on traits, rather than on token individuals, because the fitnesses of token organisms (as opposed to their actual survivorship and degree of reproductive success) are almost always unknowable. This point has ramifications for the question of how Darwin’s theory of evolution and R. A. Fisher’s are conceptually different. (shrink)

Digital Twins are conceptualised in the academic technical discourse as real-time realistic digital representations of physical entities. Originating from product engineering, the Digital Twin quickly advanced into other fields, including the life sciences and earth sciences. Digital Twins are seen by the tech sector as the new promising tool for efficiency and optimisation, while governmental agencies see it as a fruitful means for improving decision-making to meet sustainability goals. A striking example of the latter is the European Commission who wishes (...) to delegate a significant role to Digital Twins in addressing climate change and supporting Green Deal policy. As Digital Twins give rise to high expectations, ambitions, and are being entrusted important societal roles, it is crucial to critically reflect on the nature of Digital Twins. In this article, we therefore philosophically reflect on Digital Twins by critically analysing dominant conceptualisations, the assumptions underlying them, and their normative implications. We dissect the concept and argue that a Digital Twin does not merely fulfil the role of being a representation, but is in fact a steering technique used to direct a physical entity towards certain goals by means of multiple representations. Currently, this steering seems mainly fuelled by a reductionist approach focused on efficiency and optimisation. However, this is not the only direction from which a Digital Twin can be thought and, consequently, designed and deployed. We therefore set an agenda based on a critical understanding of Digital Twins that helps to draw out their beneficial potential, while addressing their potential issues. (shrink)

This paper offers a simple response to the Moral Twin Earth (MTE) objection to Naturalist Moral Realism (NMR). NMR typically relies on an externalist metasemantics such as a causal theory of reference. The MTE objection is that such a theory predicts that terms like ‘good’ and ‘right’ have a different reference in certain twin communities where it’s intuitively clear that the twins are talking about the same thing when using ‘good’. I argue that Boyd’s causal regulation theory, the original target (...) of the MTE objection, was never vulnerable to this objection. The theory contains an epistemic constraint on reference which implies that either the property that causally regulates uses of ‘good’ isn’t different for the twin communities or, in scenarios where the reference is different, the communities diverge in ways where it’s not intuitively clear that ‘good’ has the same reference for them. (shrink)

This paper presents a new challenge for libertarianism. The problem, in a nutshell, is that libertarianism appears to self-destruct in cases where conjoined twins—who share body parts—disagree over what to do with them. The problem is explored, and some solutions are proposed. The verdict is that accepting any of them will make libertarianism harder to defend.

In his recent book Physicalism, Daniel Stoljar argues that there is no version of physicalism that is both true and deserving of the name. His argument employs a variation of Hilary Putnam’s famous twin-earth story, which Stoljar calls “the twin-physics world.” In this paper, I challenge Stoljar’s use of the twin-physics world. The upshot of that challenge, I argue, is that Stoljar fails to show, concerning the versions of physicalism for which he grants the possibility of being true, that none (...) of them is deserving of the name. (shrink)

Deliberative democracy depends on carefully designed institutional frameworks-such as participant selection, facilitation methods, and decision-making mechanisms-that shape how deliberation occurs. However, determining which institutional design best suits a given context often proves difficult when relying solely on real-world observations or laboratory experiments, which can be resource-intensive and hard to replicate. To address these challenges, this paper explores Digital Twin (DT) technology as a regulatory sandbox for deliberative democracy. DTs enable researchers and policymakers to run "what-if" scenarios on varied deliberative designs (...) in a controlled virtual environment by creating dynamic, computer-based models that mirror real or synthetic data. This makes systematic analysis of the institutional design possible without the practical constraints of real-world or lab-based settings. The paper also discusses the limitations of this approach and outlines key considerations for future research. (shrink)

In this article, I examine a new concept of “Twin Memory’ which has emerged in memory classification research of conscious and unconscious memory representations. It is to analyse the presence of twin memory among the various memory systems, and also to provide a platform for the twin memory “anatomy” in the field of cognitive science, neuropsychology and neuroscience.

Various cases of conjoined twinning have been presented as problems for the animalist view that we are animals. In some actual and possible cases of human dicephalus that have been discussed in the literature, it is arguable that there are two persons but only one human animal. It is also tempting to believe that there are two persons and one animal in possible instances of craniopagus parasiticus that have been described. Here it is argued that the animalist can admit (...) that these are cases in which human persons are not animals, without forfeiting the title “animalist.” It is also shown that this is not only an option but also a well-motivated and plausible option for the animalist. Seeing this requires getting clear on what the word “we” should be thought to include in the animalist's claim that we are animals. Here animalism is defended against twinning objections by figuring out how to view the scope of the animalist's identity claim. (shrink)

Deliberative democracy relies on well-designed institutional frameworks-like participant selection, facilitation, and decision-making. Yet identifying the best design for a given context is challenging, as real-world and lab-based studies are often costly, time-consuming, and difficult to replicate. This commentary proposes Digital Twin (DT) technology as a regulatory sandbox for deliberative democracy. By simulating dynamic, data-driven models of real or synthetic communities, DTs allow researchers and policymakers to test alternative designs through controlled "what-if" scenarios, free from real-world constraints. The commentary also examines (...) limitations and key directions for future research. (shrink)

Time contraction is not a property of the moving body. Permanent contraction is against the constancy of the speed of light. Einstein uses wrong units of measurement and comes to wrong conclusions. We use the translation of the article "On the electrodynamics of moving bodies".

What is it to be a woman? What is it to be a man? We start by laying out desiderata for an analysis of 'woman' and 'man': descriptively, it should link these gender categories to sex biology without reducing them to sex biology, and politically, it should help us explain and combat traditional sexism while also allowing us to make sense of the activist view that gendering should be consensual. Using a Putnam-style 'Twin Earth' example, we argue that none of (...) the existing analyses in the feminist literature succeeds in meeting all of our desiderata. Finally, we propose a positive account that we believe can satisfy all the desiderata outlined. According to our theory, the genders 'woman' and 'man' are individuated not by their contemporary connections to sex biology, but by their historical continuity with classes that were originally closely connected to sex biology. (shrink)

Iglesias et al. (2025) argue that digital twins could serve as tools for achieving certain person-span extension goods, specifically legacy/impact and relational aims. The former pertain to broadly...

Physicists Brian Greene and Max Tegmark both make variants of the claim that if the universe is infinite and matter is roughly uniformly distributed, then there are infinitely many “people with the same appearance, name and memories as you, who play out every possible permutation of your life choices.” In this paper I argue that--while our current best theories in astrophysics may allow one to conclude that we have infinitely many duplicates whose lives are identical to our own from start (...) to finish--without either further advances in physics or advances in fields like biology, psychology, neuroscience, and philosophy, Greene’s and Tegmark’s claims about the ways in which our duplicates lives will differ from our own are not a consequence of our best current scientific theories. Rather, I argue that Greene and Tegmark’s conclusions rely on philosophically imprecise usages of the language of “possibility.”. (shrink)

The paper presents two objections against Putnam’s Twin Earth argument, which was intended to secure semantic externalism. I first claim that Putnam’s reasoning rests on two assumptions and then try to show why these assumptions are contentious. The first objection is that, given what we know about science, it is unlikely that there are any natural-kind terms whose extension is codetermined by a small set of microstructures required by Putnam’s indexical account of extension determination. The second objection is that there (...) may not be a plausible concept of a speech community whose adoption would classify Oscar and Twin Oscar as members of different speech communities and, at the same time, render Oscar and Twin Oscar as being in the same psychological state. I contend that Putnam’s argument fails because both objections are justified. (shrink)

I say that it’s philosophically inexpensive because I think it is more convincing than any other Twin-Earth thought experiment in that it sidesteps many of the standard objections to the usual thought experiments. I also discuss narrow contents and give an analysis of Putnam’s original argument.

Separation of institutions, functions and personnel – Checks and balances – Hungary, Poland, Czechia, Slovakia – Short tradition of separation of powers in Central Europe – Fragile interwar systems of separation of powers – Communist principle of centralisation of power – Technocratic challenge to separation of powers during the EU accession – One-sided checks on the elected branches and empowering technocratic elitist institutions – Populist challenge to separation of powers in the 2010s – Re-politicising of the public sphere, removing most (...) checks on the elected branches, and curtailing and packing the unelected institutions – Technocratic and populist challenges to separation of powers interrelated more than we thought. (shrink)

Did you ever wonder why you are sometimes too tired to watch a film, and would rather watch some TV show? And then, you might end up watching five or six hours and binge watch an entire season, and yet feel too tired to commit yourself to a single 2-hour film piece. The purpose of this paper is threefold. First, I will try to investigate whether there are any ontological differences in the form of a film or a television show. (...) Second, I will try to connect the newest neurological and psychological research regarding binging and attention span and see how seriality influences our brains. I will use the recent neurological findings to try to answer the question of why it seems easier to watch the same number of episodes rather than a single movie. Third, I will use David Lynch's and Mark Frost's third season of Twin Peaks as an example illustrating the blurry borders between a television show and a film, while contrasting it to the binge-watching phenomenon. (shrink)

Rules serve many important functions in society. One such function is to codify, and make public and enforceable, a society's desired prescriptions and proscriptions. This codification means that rules come with predefined punishments administered by third parties. We argue that when we look at how third parties punish rule violations, we see that rules and their punishments often serve dual functions. They support and help to maintain cooperation as it is usually theorized, but they also facilitate the domination of marginalized (...) others. We begin by reviewing literature on rules and third-party punishment, arguing that a great deal of punishment research has neglected to consider the unique power of codified rules. We also argue that by focusing on codified rules, it becomes clear that the enforcement of such rules via third-party punishment is often used to exert control, punish retributively, and oppress outgroup members. By challenging idealized theory of rules as facilitators of social harmony, we highlight their role in satisfying personal punishment motives, and facilitating discrimination in a way that is uniquely justifiable to those who enforce them. (shrink)

There have been times in the history of ethical theory, especially in this century, when moral realism was down, but it was never out. The appeal of this doctrine for many moral philosophers is apparently so strong that there are always supporters in its corner who seek to resuscitate the view. The attraction is obvious: moral realism purports to provide a precious philosophical good, viz., objectivity and all that this involves, including right answers to (most) moral questions, and the possibility (...) of knowing those answers. In the last decade, moral realism has re-entered the philosophical ring in powerful-looking naturalistic form. ln this paper we provide a dialectical overview: we situate the new wave position itself, and also our objections to it, in the context of the evolving program of philosophical naturalism in 20th century analytic philosophy. We seek to show that although this new contender might initially look like championship material, it succumbs to punches surprisingly similar to those that knocked out the old-fashioned versions of naturalist moral realism. (shrink)

The Life Insurance industry is undergoing a profound digital transformation, transitioning from traditional, static methodologies to agile, data-intelligent ecosystems capable of adapting to dynamic customer demands and stringent regulatory complexities. At the forefront of this shift is the adoption of digital twins—high-fidelity virtual replicas of physical systems, processes, and assets—specifically for testing and optimizing Life Insurance platforms. This paper provides a deep dive into the role of Digital twins in the Life Insurance domain, exploring their powerful applications in underwriting, policy (...) lifecycle management, and claims processing. By accurately simulating complex, real-world scenarios, Digital twins enable predictive testing environments that refine system resilience, preemptively identify risk exposures, and ensure operational continuity. Through this sophisticated digital infrastructure, insurers gain a transformative tool for enhancing precision, boosting reliability, and driving efficiency in core insurance processes. This research investigates the architecture, applications, and strategic trajectory of Digital twins as next generation testing mechanisms reshaping Life Insurance. (shrink)

What considerations place genuine constraints on an adequate semantics for normative and evaluative expressions? Linguists recognize facts about ordinary uses of such expressions and competent speakers’ judgments about which uses are appropriate. The contemporary literature reflects the widespread assumption that linguists don’t rely upon an additional source of data—competent speakers’ judgments about possible disagreement with hypothetical speech communities. We have several good reasons to think that such judgments are not probative for semantic theorizing. Therefore, we should accord these judgments no (...) probative value for the development of a semantics for our moral terms. Such judgments can no longer be presumed to put pressure on theories according to which our moral expressions share a semantics with ordinary, descriptive terms. Many rivals to pure, Descriptivist theories count among their advantages the ability to accommodate these judgments. If these judgments have no probative value, such theories lose an important source of support. (shrink)

In what follows, I suggest that, against most theories of time, there really is an actual present, a now, but that such an eternal moment cannot be found before or after time. It may even be semantically incoherent to say that such an eternal present exists since “it” is changeless and formless (presumably a dynamic chaos without location or duration) yet with creative potential. Such a field of near-infinite potential energy could have had no beginning and will have no end, (...) yet within it stirs the desire to experience that brings forth singularities, like the one that exploded into the Big Bang (experiencing itself through relative and relational spacetime). From the perspective of the eternal now of near-infinite possibilities (if such a sentence can be semantically parsed at all), there is only the timeless creative present, so the Big Bang did not happen some 13 billion years ago. Inasmuch as there is neither time past nor time future nor any time at all at the null point of forever, we must understand the Big Bang (and all other events) as taking place right here and now. In terms of the eternal now, the beginning is happening now and we just appeared (and are always just appearing) to witness it. The rest is all conscious construction; time and experience are so entangled, they need each other to exist. (shrink)

In a recent paper, Jiri Benovsky argues that the bundle theory and the substratum theory, traditionally regarded as ‘deadly enemies’ in the metaphysics literature, are in fact ‘twin brothers’. That is, they turn out to be ‘equivalent for all theoretical purposes’ upon analysis. The only exception, according to Benovsky, is a particular version of the bundle theory whose distinguishing features render unappealing. In the present reply article, I critically analyse these undoubtedly relevant claims, and reject them.

The project centers on the development and deployment of live digital twins for power plants, designed to seamlessly integrate with existing monitoring and database systems. These digital twins act as dynamic, real-time virtual replicas of physical power plants, capturing the intricate details of plant operations, infrastructure, and environmental interactions. The primary objective is to leverage this technology to enhance the construction, operation, and maintenance phases of power plant management. By continuously receiving real-time data from various operational sensors, equipment, and external (...) monitoring sources, the digital twin models can simulate real-world conditions, providing a holistic view of plant performance. This includes critical output parameters such as energy generation, spill rates, and head loss, particularly in the context of hydroelectric plants. The digital twins serve as a powerful tool for optimizing energy production, identifying potential issues before they escalate, and facilitating proactive maintenance strategies, thereby minimizing downtime and maximizing efficiency. Furthermore, these models allow for a more informed and data-driven approach to plant management, ensuring that every aspect of plant performance, from structural integrity to environmental impact, is closely monitored and analyzed. The integration of digital twin technology into operational workflows enables plant operators and engineers to make smarter, more efficient decisions based on real-time, actionable insights. This project not only aims to improve the day-to-day functionality of power plants but also sets the stage for future advancements in power plant technology, contributing to the broader goals of sustainability, energy efficiency, and the long-term viability of energy infrastructure. By embracing this innovative approach, the project seeks to usher in a new era of smarter, more sustainable power plant management. (shrink)

In this paper, I explore several versions of the bundle theory and the substratum theory and compare them, with the surprising result that it seems to be true that they are equivalent (in a sense of 'equivalent' to be specified). In order to see whether this is correct or not, I go through several steps : first, I examine different versions of the bundle theory with tropes and compare them to the substratum theory with tropes by going through various standard (...) objections and arguing for a tu quoque in all cases. Emphasizing the theoretical role of the substratum and of the relation of compresence, I defend the claim that these views are equivalent for all theoretical purposes. I then examine two different versions of the bundle theory with universals, and show that one of them is, here again, equivalent to the substratum theory with universals, by examining how both views face the famous objection from Identity of Indiscernibles in a completely parallel way. It is only the second, quite extreme and puzzling, version of the bundle theory with universals that is not be equivalent to any other view; and the diagnosis of why this is so will show just how unpalatable the view is. Similarly, only a not-so-palatable version of the substratum theory is genuinely different from the other views; and here again it's precisely what makes it different that makes it less appealing. (shrink)

The paper introduces and utilizes a few new concepts: “nonstandard Peano arithmetic”, “complementary Peano arithmetic”, “Hilbert arithmetic”. They identify the foundations of both mathematics and physics demonstrating the equivalence of the newly introduced Hilbert arithmetic and the separable complex Hilbert space of quantum mechanics in turn underlying physics and all the world. That new both mathematical and physical ground can be recognized as information complemented and generalized by quantum information. A few fundamental mathematical problems of the present such as Fermat’s (...) last theorem, four-color theorem as well as its new-formulated generalization as “four-letter theorem”, Poincaré’s conjecture, “P vs NP” are considered over again, from and within the new-founding conceptual reference frame of information, as illustrations. Simple or crucially simplifying solutions and proofs are demonstrated. The link between the consistent completeness of the system mathematics-physics on the ground of information and all the great mathematical problems of the present (rather than the enumerated ones) is suggested. (shrink)

The Twin Earth thought experiment invites us to consider a liquid that has all of the superficial properties associated with water (clear, potable, etc.) but has entirely different deeper causal properties (composed of “XYZ” rather than of H2O). Although this thought experiment was originally introduced to illuminate questions in the theory of reference, it has also played a crucial role in empirically informed debates within the philosophy of psychology about people’s ordinary natural kind concepts. Those debates have sought to accommodate (...) an apparent fact about ordinary people’s judgments: Intuitively, the Twin Earth liquid is not water. We present results from four experiments showing that people do not, in fact, have this intuition. Instead, people tend to have the intuition that there is a sense in which the liquid is not water but also a sense in which it is water. We explore the implications of this finding for debates about theories of natural kind concepts, arguing that it supports views positing two distinct criteria for membership in natural kind categories – one based on deeper causal properties, the other based on superficial, observable properties. (shrink)

The celebrated "Twin Earth" arguments of Hilary Putnam (1975) and Tyler Burge (1979) aim to establish that some intentional states logically depend on facts external to the subjects of those states. Ascriptions of states of these kinds to a thinker entail that the thinker's environment is a certain way. It is not possible that the thinker could be in those very intentional states unless the environment is that way...