Literacy is an essential skill. Learning to read is a requirement for becoming a self-providing human being. However, while spoken language is acquired naturally with exposure to language without explicit instruction, reading and writing need to be taught explicitly. Decades of research have shown that well-structured teaching of phonological awareness, letter knowledge, and letter-to-sound mapping is crucial in building solid foundations for the acquisition of reading. During the COVID-19 pandemic, children worldwide did not have access to consistent and structured teaching (...) and are, as a consequence, predicted to be behind in the development of their reading skills. Subsequent evidence confirms this prediction. With the best evidence-based practice in mind, we developed an online version of a well-structured early literacy training program for 5-year-old children. This 2-week online Reading Camp program is designed for pre-K children. It incorporates critical components of the fundamental skills essential to learning to read and is taught online in an interactive, multi-sensory, and peer-learning environment. We measure the participants’ literacy skills and other related skills before and after participating in the online Reading Camp and compare the results to no-treatment controls. Results show that children who participated in the online Reading Camp improved significantly on all parameters in relation to controls. Our results demonstrate that a well-structured evidence-based reading instruction program, even if online and short-term, benefits 5-year-old children in learning to read. With the potential to scale up this online program, the evidence presented here, alongside previous evidence for the efficacy of the in-person program, indicates that the online Reading Camp program is effective and can be used to tackle a variety of questions regarding structural and functional plasticity in the early stages of reading acquisition. (shrink)

This paper explores a special kind of loop of grounding: cosmic loops. A cosmic loop is a loop that intuitively requires us to go "around" the entire universe to come back to the original ground. After describing several kinds of cosmic loop scenarios, I will discuss what we can learn from these scenarios about constraints on grounding; the conceivability of cosmic loops; the possibility of cosmic loops; and the prospects for salvaging local reflexivity, asymmetry and transitivity (...) of grounding in a world containing a cosmic loop of ground. The considerations raised in this paper also bear on what we should think about relations that are meant to support grounding relations: in particular, revisions to theories of the part-whole relation are discussed. (shrink)

Background: Newer “closed-loop” neurostimulation devices in development could, in theory, induce changes to patients’ personalities and self-perceptions. Empirically, however, only limited data of patient and family experiences exist. Responsive neurostimulation (RNS) as a treatment for refractory epilepsy is the first approved and commercially available closed-loop brain stimulation system in clinical practice, presenting an opportunity to observe how conceptual neuroethical concerns manifest in clinical treatment. Methods: We conducted ethnographic research at a single academic medical center with an active RNS (...) treatment program and collected data via direct observation of clinic visits and in-depth interviews with 12 patients and their caregivers. We used deductive and inductive analyses to identify the relationship between these devices and patient changes in personality and self-perception. Results: Participants generally did not attribute changes in patients’ personalities or self-perception to implantation of or stimulation using RNS. They did report that RNS affected patients’ experiences and conceptions of illness. In particular, the capacity to store and display electrophysiological data produced a common frame of reference and a shared vocabulary among patients and clinicians .Discussion: Empirical experiences of a clinical population being treated with closed-loop neuromodulation do not corroborate theoretical concerns about RNS devices described by neuroethicists and technology developers. However, closed-loop devices demonstrated an ability to change illness experiences. Even without altering identify and self-perception, they provided new cultural tools and metaphors for conceiving of epilepsy as an illness and of the process of diagnosis and treatment. These findings call attention to the need to situate neuroethical concerns in the broader contexts of patients’ illness experiences and social circumstances. (shrink)

The ‘causal-constitution’ fallacy, the ‘cognitive bloat’ worry, and the persisting theoretical confusion about the fundamental difference between the hypotheses of embedded (HEMC) and extended (HEC) cognition are three interrelated worries, whose common point—and the problem they accentuate—is the lack of a principled criterion of constitution. Attempting to address the ‘causal-constitution’ fallacy, mathematically oriented philosophers of mind have previously suggested that the presence of non-linear relations between the inner and the outer contributions is sufficient for cognitive extension. The abstract idea of (...) non-linearity, however, can be easily misunderstood and has, in the past, led to incorrect and counterintuitive conclusions about what may count as part of one’s overall cognitive system. In order to prevent any further mistakes I revisit dynamical systems theory to study the nature of the continuous mutual interactions that give rise to the aforementioned non-linear relations. Moreover, focusing on these interactions will allow us to provide two distinct arguments in support of the ontological postulation of extended cognitive systems, as well as an objective criterion of constitution. Accordingly, I put forward a version of HEC that treats continuous mutual interactions (and the resultant non-linear relations) not just as sufficient but also as necessary for cognitive extension. Such a qualified version of HEC may exclude certain alleged cases of cognitive extension where the agent does not mutually interact with his artifacts (e.g., shopping lists and directory services), but it is immune both to the ‘causal-constitution’ fallacy and the ‘cognitive bloat’ worry, and it can be sharply distinguished from HEMC. (shrink)

Human behavior is not always independent of the ways in which humans are scientifically classified. That there are looping effects of human kinds has been used as an argument for the methodological separation of the natural and the human sciences and to justify social constructionist claims. We suggest that these arguments rely on false presuppositions and present a mechanisms-based account of looping that provides a better way to understand the phenomenon and its theoretical and philosophical implications.

In this paper, I discuss whether the results of loop quantum gravity (LQG) constitute a fatal blow to Humeanism. There is at least a prima facie reason for believing so: while Humeanism regards spatiotemporal relations as fundamental, LQG describes the fundamental layer of our reality in terms of spin networks, which are not in spacetime. However, the question should be tackled more carefully. After explaining the importance of the debate on the tenability of Humeanism in light of LQG, and (...) having presented the Humean doctrine, I review two cases which present serious threats to Humeanism, one concerning the fundamentality of vectorial quantities and the other concerning quantum entanglement. In particular, I recall the strategies that are usually employed in these two cases in order to save Humeanism: in the first case, the strategy consists in amending the characterization of the Humean mosaic; in the second case, it consists in adopting a realist or nomological interpretation of the wave function. These solutions will turn out to be helpful in my discussion of LQG where, after describing LQG, I show that Humeans might save their doctrine either by endorsing a realist interpretation of spin networks, or by giving them a nomological status and, at the same time, by revisiting the characterization of the Humean mosaic. However, I conclude that both solutions are wanting. (shrink)

According to Hugh Mellor in Real Time II, assuming the logical independence of causal facts and the ‘law of large numbers’, causal loops are impossible because if they were possible they would produce inconsistent sets of frequencies. I clarify the argument, and argue that it would be preferable to abandon the relevant independence assumption in the case of causal loops.

Endocrinologists apply the idea of feedback loops to explain how hormones regulate certain bodily functions such as glucose metabolism. In particular, feedback loops focus on the maintenance of the plasma concentrations of glucose within a narrow range. Here, we put forward a different, organicist perspective on the endocrine regulation of glycaemia, by relying on the pivotal concept of closure of constraints. From this perspective, biological systems are understood as organized ones, which means that they are constituted of a set of (...) mutually dependent functional structures acting as constraints, whose maintenance depends on their reciprocal interactions. Closure refers specifically to the mutual dependence among functional constraints in an organism. We show that, when compared to feedback loops, organizational closure can generate much richer descriptions of the processes and constraints at play in the metabolism and regulation of glycaemia, by making explicit the different hierarchical orders involved. We expect that the proposed theoretical framework will open the way to the construction of original mathematical models, which would provide a better understanding of endocrine regulation from an organicist perspective. (shrink)

The aim of this paper is to present a loop-free decision procedure for modal propositional logics K4, S4 and S5. We prove that the procedure terminates and that it is sound and complete. The procedure is based on the method of Socratic proofs for modal logics, which is grounded in the logic of questions IEL.

The era of AI-based decision-making fast approaches, and anxiety is mounting about when, and why, we should keep “humans in the loop” (“HITL”). Thus far, commentary has focused primarily on two questions: whether, and when, keeping humans involved will improve the results of decision-making (making them safer or more accurate), and whether, and when, non-accuracy-related values—legitimacy, dignity, and so forth—are vindicated by the inclusion of humans in decision-making. Here, we take up a related but distinct question, which has eluded (...) the scholarship thus far: does it matter if humans appear to be in the loop of decision-making, independent from whether they actually are? In other words, what is stake in the disjunction between whether humans in fact have ultimate authority over decision-making versus whether humans merely seem, from the outside, to have such authority? Our argument proceeds in four parts. First, we build our formal model, enriching the HITL question to include not only whether humans are actually in the loop of decision-making, but also whether they appear to be so. Second, we describe situations in which the actuality and appearance of HITL align: those that seem to involve human judgment and actually do, and those that seem automated and actually are. Third, we explore instances of misalignment: situations in which systems that seem to involve human judgment actually do not, and situations in which systems that hold themselves out as automated actually rely on humans operating “behind the curtain.” Fourth, we examine the normative issues that result from HITL misalignment, arguing that it challenges individual decision-making about automated systems and complicates collective governance of automation. (shrink)

The ontological issues at stake given the theory of loop quantum gravity include the status of spacetime, the nature and reality of spin-networks, the relationship of classical spacetime to issues of causation and the status of the abstract-concrete distinction. I this paper I argue that, while spacetime seems to disappear, the spirit of substantival spacetime lives on under certain interpretations of the theory. Moreover, in order for there to be physical spin-networks, and not merely mathematical artifacts, I argue that (...) we must interpret the theory as including a substantival background manifold. This latter result is important for any project which interprets spacetime as an emergent structure from physical spin-networks. (shrink)

Epistemologists spend a great deal of time thinking about how we should respond to our evidence. They spend far less time thinking about the ways that evidence can be acquired in the first place. This is an oversight. Some ways of acquiring evidence are better than others. Many normative epistemologies struggle to accommodate this fact. In this article I develop one that can and does. I identify a phenomenon – epistemic feedback loops – in which evidence acquisition has gone awry, (...) with the result that even beliefs based on the evidence are irrational. Examples include evidence acquired under the influence of confirmation bias and evidence acquired under the influence of cognitively penetrated experiences caused by implicit bias. I then develop a theoretical framework which enables us to understand why beliefs that are the outputs of epistemic feedback loops are irrational. Finally, I argue that many popular approaches to epistemic normativity may need to be abandoned on the grounds that they cannot comfortably explain feedback loops. The scope of this last claim is broad: it includes almost all contemporary theories of justified/rational belief and of the epistemology of cognitive penetration. (shrink)

The current debate on closed-loop brain devices (CBDs) focuses on their use in a medical context; possible criminal justice applications have not received scholarly attention. Unlike in medicine, in criminal justice, CBDs might be offered on behalf of the State and for the purpose of protecting security, rather than realising healthcare aims. It would be possible to deploy CBDs in the rehabilitation of convicted offenders, similarly to the much-debated possibility of employing other brain interventions in this context. Although such (...) use of CBDs could in principle be consensual, there are significant differences between the choice faced by a criminal offender offered a CBD in the context of criminal justice, and that faced by a patient offered a CBD in an ordinary healthcare context. Employment of CBDs in criminal justice thus raises ethical and legal intricacies not raised by healthcare applications. This paper examines some of these issues under three heads: autonomy, human rights, and accountability. (shrink)

Closed Loop medical devices such as Closed Loop Deep Brain Stimulation and Brain Computer Interface are some of the emerging neurotechnologies. New generations of implantable brain–computer interfaces have recently gained success in human clinical trials. These implants detect specific neuronal patterns and provide the subject with information to respond to these patterns. Further, Closed Loop brain devices give control to the subject so that he can respond and decide on a therapeutic goal. Although the implants have improved (...) subjects’ quality of life, their use has raised varied ethical concerns. The aim of this study is to provide an overview of the ethical implications specific to the therapeutic goals of closed loop brain implants. The authors analyze the related work qualitatively and quantitatively so as to help readers in understanding the various ethical implications of closed loop brain implants. (shrink)

Recent philosophy of measurement has emphasized the existence of both diachronic and synchronic “loops,” or feedback processes, in the epistemic achievements of measurement. A widespread response has been to conclude that measurement outcomes do not convey interest-independent facts about the world, and that only a coherentist epistemology of measurement is viable. In contrast, I argue that a form of measurement realism is consistent with these results. The insight is that antecedent structure in measuring spaces constrains our empirical procedures such that (...) successful measurement conveys a limited, but veridical knowledge of “fixed points,” or stable, interest- independent features of the world. (shrink)

Segregation of chromosomes during mitosis requires the interaction of dynamic microtubules with the kinetochore, a large protein structure established on the centromere region of sister chromatids. The core microtubule‐binding activity of the kinetochore resides in the KMN network, an outer kinetochore complex. As part of the KMN network, the Ndc80 complex, which is composed of Ndc80, Nuf2, Spc24, and Spc25, is able to bind directly to microtubules and has the ability to track with depolymerizing microtubules to produce chromosome movement. The (...) Ndc80 complex binds directly to microtubules through a calponin homology domain and an unstructured tail in the N terminus of the Ndc80 protein. A recent flurry of papers has highlighted the importance of an internal loop region in Ndc80 in establishing end‐on attachment to microtubules. Here I discuss these recent findings that suggest that the Ndc80 internal loop functions as a binding site for proteins required for kinetochore‐microtubule interactions. (shrink)

This article argues that the causal loops that occur in some time-travel scenarios and in certain solutions of the theory of relativity are no more mysterious than the infinitely descending causal chains familiar from Newtonian mechanics.

In this article, we explore how deep brain stimulation (DBS) devices designed to “close the loop”—to automatically adjust stimulation levels based on computational algorithms—may risk taking the individual agent “out of the loop” of control in areas where (at least apparent) conscious control is a hallmark of our agency. This is of particular concern in the area of psychiatric disorders, where closed-loop DBS is attracting increasing attention as a therapy. Using a relational model of identity and agency, (...) we consider whether DBS designed for psychiatric regulation may require special attention to agency. To do this, we draw on philosophical work on relational identity and agency, connecting it with reports from people using first-generation DBS devices for depression and obsessive-compulsive disorder. We suggest a way to extend a notion of relational agency to encompass neural devices. (shrink)

The paper surveys the possibility of keeping a neo-Kantian approach in the face of Loop Quantum Gravity. Together with a preliminary analysis of Cassirer’s re-interpretation of Kantian philosophy that allowed him to harmonize the a priori cognitions with the theory of relativity and quantum mechanics, it will focus on the distinction between constitutive and regulativea priori. In this way, the paper will suggest that despite Rovelli’s refutation of Kant’s interpretation of space and time, he seems, at least implicitly, to (...) hold to a couple of neo-Kantian assumptions: the usage of constitutivea priori principlessuch as granularity, indeterminism and partially relation, and the claim for functionalism as a rule in ordering the ‘appearances’. (shrink)

The aim of this paper is to present a loop-free decision procedure for modal propositional logics K4, S4 and S5. We prove that the procedure terminates and that it is sound and complete. The procedure is based on the method of Socratic proofs for modal logics, which is grounded in the logic of questions IEL.

According to Hugh Mellor in Real Time II (1998, Ch. 12), assuming the logical independence of causal facts and the 'law of large numbers', causal loops are impossible because if they were possible they would produce inconsistent sets of frequencies. I clarify the argument, and argue that it would be preferable to abandon the relevant independence assumption in the case of causal loops.

This volume explores the arrangement of science, technology, society, and education. Using the concept of "feedback loop", this book processes subjects dear to the work of Joseph C. Pitt: technology as humanity at work, pragmatism, Sicilian realism, pragmatist pedagogy, instrumentation in science, and more.

Chromosomal rearrangements frequently occur at specific places (“hot spots”) in the genome. These recombination hot spots are usually separated by 50–100 kb regions of DNA that are rarely involved in rearrangements. It is quite likely that there is a correlation between the above‐mentioned distances and the average size of DNA loops fixed at the nuclear matrix. Recent studies have demonstrated that DNA loop anchorage regions can be fairly long and can harbor DNA recombination hot spots. We previously proposed that (...) chromosomal DNA loops may constitute the basic units of genome organization in higher eukaryotes. In this review, we consider recombination between DNA loop anchorage regions as a possible source of genome evolution. (shrink)

During the first two decades of the Cold War, a new kind of academic figure became prominent in American public life: the credentialed social scientist or expert in the sciences of administration who was also, to use the parlance of the time, a “man of affairs.” Some were academic high-fliers conscripted into government roles in which their intellectual and organizational talents could be exploited. McGeorge Bundy, Walt Rostow, and Robert McNamara are the archetypes of such persons. An overlapping group of (...) scholars became policymakers and political advisers on issues ranging from social welfare provision to nation-building in emerging postcolonial states. Many of these men—and almost without exception they were men—were also consummate operators within the patronage system that grew up around American universities after World War II. Postwar leaders of the social and administrative sciences such as Talcott Parsons and Herbert Simon were skilled scientific brokers of just this sort: good “committee men,” grant-getters, proponents of interdisciplinary inquiry, and institution-builders. This hard-nosed, suit-wearing, business-like persona was connected to new, technologically refined forms of social science. No longer sage-like social philosophers or hardscrabble, number-crunching empiricists, academic human scientists portrayed themselves as possessors of tools and programs designed for precision social engineering. Antediluvian “social science” was eschewed in favour of mathematical, behavioural, and systems-based approaches to “human relations” such as operations research, behavioral science, game theory, systems theory, and cognitive science. (shrink)

It is shown that the Riemannian curvature of the 3-dimensional hypersurfaces in space-time, described by the Wilson loop integral, can be represented by a quaternion quantum operator induced by the SU(2) gauge potential, thus providing a justification for quaternion quantum gravity at the Tev energy scale.

Purpose: Ernst von Glasersfeld’s question concerning the relationship between scientific/ rational knowledge and the domain of wisdom and how these forms of knowledge come about is the starting point. This article aims at developing an epistemological as well as methodological framework that is capable of explaining how profound change can be brought about in various contexts, such as in individual cultivation, in organizations, in processes of radical innovation, etc. This framework is based on the triple-loop learning strategy and the (...) U-theory approach, which opens up a perspective on how the domains of scientific/rational knowledge, constructivism, and wisdom could grow together more closely. Design/Structure: This article develops a strategy which is referred to as “tripleloop learning,” which is not only the basis for processes of profound change, but also brings about a new dimension in the field of learning and knowledge dynamics: the existential realm and the domain of wisdom. A concrete approach that puts into practice the tripleloop learning strategy is presented. The final section shows, how these concepts can be interpreted in the context of the constructivist approach and how they might offer some extensions to this paradigm. Findings: The process of learning and change has to be extended to a domain that concerns existential issues as well as questions of wisdom. Profound change can only happen if these domains are taken into consideration. The tripleloop learning strategy offers a model that fulfills this criterion. It is an “epistemo-existential strategy” for profound change on various levels. Conclusions: The (cognitive) processes and attitudes of receptivity, suspension, redirecting, openness, deep knowing, as well as “profound change/innovation from the interior” turn out to be core concepts in this process. They are compatible with constructivist concepts. Von Glasersfeld’s concept of functional fitness is carried to an extreme in the suggested approach of profound change and finds an extension in the existential domain. Key words: Double-loop learning, individual cultivation, (radical) innovation, knowledge creation, knowledge society, personality development, presencing, profound change, triple-loop learning, U-theory, wisdom. (shrink)

Closed-loop transcutaneous auricular vagal nerve stimulation was officially proposed in 2020. This work firstly reviewed two existing CL-taVNS forms: motor-activated auricular vagus nerve stimulation and respiratory-gated auricular vagal afferent nerve stimulation, and then proposed three future CL-taVNS systems: electroencephalography -gated CL-taVNS, electrocardiography -gated CL-taVNS, and subcutaneous humoral signals -gated CL-taVNS. We also highlighted the mechanisms, targets, technical issues, and patterns of CL-taVNS. By reviewing, proposing, and highlighting, this work might draw a preliminary blueprint for the development of CL-taVNS.

Judith Jarvis Thomson's Loop Case is particularly significant in normative ethics because it questions the validity of the intuitively plausible Doctrine of Double Effect, according to which there is a significant difference between harm that is intended and harm that is merely foreseen and not intended. Recently, Frances Kamm has argued that what she calls the Doctrine of Triple Effect, which draws a distinction between acting because-of and acting in-order-to, can account for our judgment about the Loop Case. (...) In this paper, I first argue that even if the distinction drawn by DTE can be sustained, it does not seem to apply to the Loop Case. Moreover, I question whether this distinction has any normative significance. The upshot is that I am skeptical that DTE can explain our judgment about the Loop Case. (shrink)

In the following article we first present the growing trend of incorporating neuroscience into the law, and the growing acceptance of and trust in neuroscience’s mechanistic and reductionistic explanations of the human mind. We then present and discuss some studies that show how nudging peoples’ beliefs about matters related to human agency (such as free will, decision-making, or self-control) towards a more deterministic, mechanistic and/or reductionistic conception, exerts an influence on their very actions, mentality, and brain processes. We suggest that (...) the neuroscientific view of the human mind exerts an influence on the very cognitive phenomena neuroscience falsely believes to be studying objectively. This holds especially when we consider the systematic integration of neuroscience into the public domain, such as the law. For, such an integration acts as a reinforcement of the public’s and legal decision-makers’ endorsement of and trust in neuroscience’s view of human nature that further changes how people think and act. Such looping effects of neurolaw are probably inevitable. Accordingly, we should be aware of the scope of neuroscientific explanations and be careful not to overstate neuroscientific evidence and findings in legal contexts. (shrink)

Background: Treating medication-refractory freezing of gait in Parkinson’s disease remains challenging despite several trials reporting improvements in motor symptoms using subthalamic nucleus or globus pallidus internus deep brain stimulation. Pedunculopontine nucleus region DBS has been used for medication-refractory FoG, with mixed findings. FoG, as a paroxysmal phenomenon, provides an ideal framework for the possibility of closed-loop DBS.Methods: In this clinical trial, five subjects with medication-refractory FoG underwent bilateral GPi DBS implantation to address levodopa-responsive PD symptoms with open-loop stimulation. (...) Additionally, PPN DBS leads were implanted for CL-DBS to treat FoG. The primary outcome of the study was a 40% improvement in medication-refractory FoG in 60% of subjects at 6 months when “on” PPN CL-DBS. Secondary outcomes included device feasibility to gauge the recruitment potential of this four-lead DBS approach for a potentially larger clinical trial. Safety was judged based on adverse events and explantation rate.Findings: The feasibility of this approach was demonstrated as we recruited five subjects with both “on” and “off” medication freezing. The safety for this population of patients receiving four DBS leads was suboptimal and associated with a high explantation rate of 40%. The primary clinical outcome in three of the five subjects was achieved at 6 months. However, the group analysis of the primary clinical outcome did not reveal any benefit.Interpretation: This study of a human PPN CL-DBS trial in medication-refractory FoG showed feasibility in recruitment, suboptimal safety, and a heterogeneous clinical effect in FoG outcomes. (shrink)

Can thought arise out of matter? Can self, soul, consciousness, “I” arise out of mere matter? If it cannot, then how can you or I be here? I Am a Strange Loop argues that the key to understanding selves and consciousness is the “strange loop”—a special kind of abstract feedback loop inhabiting our brains. The most central and complex symbol in your brain is the one called “I.” The “I” is the nexus in our brain, one of (...) many symbols seeming to have free will and to have gained the paradoxical ability to push particles around, rather than the reverse. How can a mysterious abstraction be real—or is our “I” merely a convenient fiction? Does an “I” exert genuine power over the particles in our brain, or is it helplessly pushed around by the laws of physics? These are the mysteries tackled in I Am a Strange Loop, Douglas Hofstadter's first book-length journey into philosophy since Gödel, Escher, Bach. Compulsively readable and endlessly thought-provoking, this is a moving and profound inquiry into the nature of mind. (shrink)

We reconstruct genetic determinism as a reductionist thesis to the effect that the molecular properties of cells can be accounted for to a great extent by their genetic outfit. The non-reductionist arguments offered at this molecular level often use the relationship between structure and function as their point of departure. By contrast, we develop a non-reductionist argument that is confined to the structural characteristics of biomolecules; no appeal to functions is made. We raise two kinds of objections against the reducibility (...) claim underlying genetic determinism. First, some conceptual distinctions at the protein level cannot be captured on a genetic basis. A one-to-many relationship between DNA sequences and proteins emerges from them. Second, the relationship between genes and proteins is characterized by explanatory loops or reciprocal explanatory dependence. The presence of proteins is explained by the transcription from corresponding DNA sequences, and the latter is in turn accounted for by the action of proteins. By contrast, a reductive account requires a unidirectional explanatory dependence. (shrink)

Machine learning algorithms reshape how people communicate, exchange, and associate; how institutions sort them and slot them into social positions; and how they experience life, down to the most ordinary and intimate aspects. In this article, we draw on examples from the field of social media to review the commonalities, interactions, and contradictions between the dispositions of people and those of machines as they learn from and make sense of each other.

What is our conception of the temporal priority of cause over effect? It is that a causal chain runs always in the earlier‐to‐later direction. Each link in the chain is a process, whose initiation is the immediate, and thus simultaneous, effect of the arrival at a particular stage of the process that constitutes the preceding link. It is the fact that it is the subsequent continuation of the process, once initiated, that calls for no explanation, which gives a temporal direction (...) to the causal chain. If there are causal chains running in the reverse as well as in the usual direction, there is a possibility of causal loops. (shrink)

Open peer commentary on the article “Subsystem Formation Driven by Double Contingency” by Bernd Porr & Paolo Di Prodi. Upshot: By analyzing Porr and Di Prodi’s model for addressing the double contingency problem, I try to take a step further by questioning the importance and implications of the loop concept in the constructivist approach.

All the typical global quantum mechanical observables are complex relative phases obtained by interference phenomena. They are described by means of some global geometric phase factor, which is thought of as the “memory” of a quantum system undergoing a “cyclic evolution” after coming back to its original physical state. The origin of a geometric phase factor can be traced to the local phase invariance of the transition probability assignment in quantum mechanics. Beyond this invariance, transition probabilities also remain invariant under (...) the operation of complex conjugation. Most important, geometric phase factors distinguish between unitary and antiunitary transformations in terms of complex conjugation. These two types of invariance functions as an anchor point to investigate the role of loops and based loops in the state space of a quantum system as well as their links and interrelations. We show that arbitrary transition probabilities can be calculated using projective invariants of loops in the space of rays. The case of the double slit experiment serves as a model for this purpose. We also represent the action of one-parameter unitary groups in terms of oppositely oriented-based loops at a fixed ray. In this context, we explain the relation among observables, local Boolean frames of projectors, and one-parameter unitary groups. Next, we exploit the non-commutative group structure of oriented-based loops in 3-d space and demonstrate that it carries the topological semantics of a Borromean link. Finally, we prove that there exists a representation of this group structure in terms of one-parameter unitary groups that realizes the topological linking properties of the Borromean link. (shrink)

Libertarians often portray the decision to use enhancement technologies purely as a matter of individual choice, affecting the person who uses them but no one else. Yet individual choices often add up to large social changes that profoundly affect the lives of other people, effectively pushing individual choices in a particular direction. It seems plausible that self-reinforcing loops such as those that have driven the adoption of technologies like cars and air-conditioners might also play a role in the adoption of (...) enhancement technologies, effectively exerting pressure on people to use a technology that they might otherwise resist. (shrink)