We develop the theory of Cκ, λi, a strongly normal filter over [MATHEMATICAL SCRIPT CAPITAL P]κλ for Mahlo κ. We prove a minimality result, showing that any strongly normal filter containing {x ∈ [MATHEMATICAL SCRIPT CAPITAL P]κλ: |x | = |x ∩ κ | and |x | is inaccessible} also contains Cκ, λi. We also show that functions can be used to obtain a basis for Cκ, λi.

The purpose of this note is to demonstrate that a weak form of club guessing on ω1 implies the existence of an Aronszajn line with no Countryman suborders. An immediate consequence is that the existence of a five element basis for the uncountable linear orders does not follow from the forcing axiom for ω-proper forcings.

Suppose that λ is the successor of a singular cardinal μ whose cofinality is an uncountable cardinal κ. We give a sufficient condition that the club filter of λ concentrating on the points of cofinality κ is not λ+-saturated.1 The condition is phrased in terms of a notion that we call weak reflection. We discuss various properties of weak reflection. We introduce a weak version of the ♣-principle, which we call ♣*−, and show that if it holds on (...) a stationary subset S of λ, then no normal filter on S is λ+-saturated. Under the above assumptions, ♣*− is true for any stationary subset S of λ which does not contain points of cofinality κ. For stationary sets S which concentrate on points of cofinality κ, we show that ♣*− holds modulo an ideal obtained through the weak reflection. (shrink)

We investigate club guessing sequences and filters. We prove that assuming V=L, there exists a strong club guessing sequence on μ if and only if μ is not ineffable for every uncountable regular cardinal μ. We also prove that for every uncountable regular cardinal μ, relative to the existence of a Woodin cardinal above μ, it is consistent that every tail club guessing ideal on μ is precipitous.

In lieu of an abstract, here is a brief excerpt of the content:Philosophy and Literature 25.2 (2001) 353-356 [Access article in PDF] Book Review The Metaphysical Club The Metaphysical Club, by Louis Menand; xii & 546 pp. New York: Farrar, Straus and Giroux, 2001, $27.00. "They didn't just want to keep the conversation going; they wanted to get to a better place" (p. 440). So much for the most prominent contemporary pragmatist, Richard Rorty, who remains unmentioned except in (...) the acknowledgments. That better place is participatory democracy (a phrase that does not appear in the book), which "means that everyone is equally in the game, but it also means that no one can opt out" (p. 441). The true name of the game is skeptical tolerance. There are no unquestionable duties or inalienable rights, no immutable natural laws, no absolute moral rules, no highest principles, no inherent virtues, no absolute standards, no stasis, no absolutely certain truth. There are no individual destinies, because the social comes before the individual, and the individual is embedded within and cannot exist without society. Scientific knowledge is always probabilistic, not necessarily because nature is indeterministic, but because we can never know enough to calculate its regularities if they exist. To wit, there are no Platonic Ideas or unchanging universals. All is change, nothing that happens is ever repeated, our general ideas and laws of nature are merely tools for getting along in the world. Above all, ideas do not refer to things, only to other ideas. What expedites our thinking is true. What expedites our acting is right. Whenever we act according to principle, rule, or law, we are making a bet that events will turn out the way [End Page 353] we think they will. If we keep this always in mind, we will never succumb to violence or war in the name of belief or principle. Whatever we believe, it could be otherwise. Such is a general summary of pragmatism as it has filtered down to the textbooks. It is (again befittingly) more or less accurate. The can-do American seeks out cash value in practical life.Oliver Wendell Holmes, Jr., William James, Charles Saunders Pierce, and John Dewey crafted the only indigenous philosophy that has so far been produced in America. Its roots are in Laplacean probability theory, Darwinian evolutionism, and Chauncey Wright's indeterminism. While James hoped to save a place for religion (if it works, go with it) and Pierce a place for God (he thought there had to be a designing intelligence to account for order), the pragmatic result is profoundly skeptical and secular. Neither Holmes nor Dewey thought that individuals imbedded in societies had any need of absolutes. Holmes said that people first decide on the basis of experience, then they deduce. Dewey said that people first behave commonsensically, then they rationalize.There is nothing as condensed as the above in Louis Menand's beautiful book on the ideas, personalities, and influence of Holmes, James, Pierce, and Dewey. I know of no clearer exposition of their ideas, and few biographers have made them come so alive. In particular, Menand's coverage of peripheral (but by no means insignificant) figures is very rich. He describes the development of graduate universities in America in detail from their autocratic beginnings to the institution of academic freedom as we know it today. University presidents, trustees, and administrators are presented luxuriously as the villains, and the professors gloriously as the heroes. Menand remarks with slight amazement that society bought the concept that professors were beholden to the public at large and not to the state or private university owners. He could have commented further on the fact that the concept of academic freedom has become virtually irrelevant in today's corporate research universities."It is a remarkable fact about the United States," Menand begins his book, "that it fought a civil war without undergoing a change in its form of government" (p. ix). This is a breathtaking fact, and I don't suppose Menand had any intent to explain it. "The Civil War swept away the slave civilization of the South, but it swept away almost the whole intellectual... (shrink)

We give some restrictions for the search for a model of the club principle with no Souslin trees. We show that ${\diamondsuit(2^\omega, [\omega]^\omega}$ , is almost constant on) together with CH and “all Aronszajn trees are special” is consistent relative to ZFC. This implies the analogous result for a double weakening of the club principle.

We characterize the situation of having at least $^{+}$-many normal ultrafilters on a measurable cardinal $\kappa$. We also show that if $\kappa$ is a compact cardinal, then $\kappa$ carries $^{+}$-many $\kappa$-complete ultrafilters, each of which extends the club filter on $\kappa$.

We show that the modal propositional logic G, originally introduced to describe the modality "it is provable that", is also sound for various interpretations using filters on ordinal numbers, for example the end-segment filters, the club filters, or the ineffable filters. We also prove that G is complete for the interpretation using end-segment filters. In the case of club filters, we show that G is complete if Jensen's principle □ κ holds for all $\kappa ; on the other (...) hand, it is consistent relative to a Mahlo cardinal that G be incomplete for the club filter interpretation. (shrink)

We show that in the [Formula: see text] extension of a certain Chang-type model of determinacy, if [Formula: see text], then the restriction of the club filter on [Formula: see text] Cof[Formula: see text] to HOD is an ultrafilter in HOD. This answers Question 4.11 of [O. Ben-Neria and Y. Hayut, On [Formula: see text]-strongly measurable cardinals, Forum Math. Sigma 11 (2023) e19].

We prove determinacy for open length ω1 games. Going further we introduce, and prove determinacy for, a stronger class of games of length ω1, with payoff conditions involving the entire run, the club filter on ω1, and a sequence of ω1 disjoint stationary subsets of ω1. The determinacy proofs use an iterable model with a class of indiscernible Woodin cardinals, and we show that the games precisely capture the theory of the minimal model for this assumption.

Uncountable superperfect forcing is tree forcing on regular uncountable cardinals κ with κ<κ=κ, using trees in which the heights of nodes that split along any branch in the tree form a club set, and such that any node in the tree with more than one immediate extension has measure-one-many extensions, where the measure is relative to some κ-complete, nonprincipal normal filter F. This forcing adds a generic of minimal degree if and only if F is κ-saturated.

Nobody should have a monopoly of the truth in this universe. The censorship and suppression of challenging ideas against the tide of mainstream research, the blacklisting of scientists, for instance, is neither the best way to do and filter science, nor to promote progress in the human knowledge. The removal of good and novel ideas from the scientific stage is very detrimental to the pursuit of the truth. There are instances in which a mere unqualified belief can occasionally be (...) converted into a generally accepted scientific theory through the screening action of refereed literature and meetings planned by the scientific organizing committees and through the distribution of funds controlled by "club opinions". It leads to unitary paradigms and unitary thinking not necessarily associated to the unique truth. This is the topic of this book: to critically analyze the problems of the official mechanisms under which current science is being administered and filtered today, along with the onerous consequences these mechanisms have on all of us. The authors, all of them professional researchers, reveal a pessimistic view of the miseries of the actual system, while a glimmer of hope remains in the "leitmotiv" claim towards the freedom in doing research and attaining an acceptable level of ethics in science. (shrink)

Through the analysis of an 18-month ethnography at an exotic dance club located in the Northeastern United States, I uncover how Latina exotic dancers manage their participation in exotic dance by deploying constructions of Latinidad as embodied cues. I focus on Playpen’s weekly event, “Latina Night,” to demonstrate how racialized, sexualized, and gendered constructs relative to Latinidad are produced and regulated in this exotic dance setting. Study participants draw on embodied markers to negotiate how their bodies are read. Those (...) markers include nationality-based appeals, time elapsed since migration, and the ability to express constructions of Latinidad through dance performance. I draw on intersectionality as a conceptual tool, filtered through a sensibility to Latina/o/x lives and experiences, to analyze the nuances of racialization as experienced by Latinas. This approach destabilizes the U.S. black–white racial binary and opens intersectionality to a more nuanced understanding of the production of Latinidad. By approaching racialization as an embodied phenomenon, I elucidate how bodily markers, beyond skin color, become imbued with racialized meaning and condition racialized erotic capital. No less important is how participants draw on racialized, gendered, and sexualized tropes to benefit racialized erotic capital. (shrink)

his is a book to broaden the mind. It brings the reader into a world only vaguely imaginable and richly enlightens it with extraordinary attention to interesting historical details. It is beautifully written and endlessly interesting.

In this paper we introduce the notion of filter on the neutrosophic crisp set, then we consider a generalization of the filter’s studies. Afterwards, we present the important neutrosophic crisp filters. We also study several relations between different neutrosophic crisp filters and neutrosophic topologies. Possible applications to database systems are touched upon.

We show that, under PFA, a coherent Suslin tree forces that every two Aronszajn trees are club-isomorphic.

We survey the use of club guessing and other PCF constructs in the context of showing that a given partially ordered class of objects does not have a largest, or a universal, element.

A filter of a sentential logic ? is Leibniz when it is the smallest one among all the ?-filters on the same algebra having the same Leibniz congruence. This paper studies these filters and the sentential logic ?+ defined by the class of all ?-matrices whose filter is Leibniz, which is called the strong version of ?, in the context of protoalgebraic logics with theorems. Topics studied include an enhanced Correspondence Theorem, characterizations of the weak algebraizability of ?+ (...) and of the explicit definability of Leibniz filters, and several theorems of transfer of metalogical properties from ? to ?+. For finitely equivalential logics stronger results are obtained. Besides the general theory, the paper examines the examples of modal logics, quantum logics and Łukasiewicz's finitely-valued logics. One finds that in some cases the existence of a weak and a strong version of a logic corresponds to well-known situations in the literature, such as the local and the global consequences for normal modal logics; while in others these constructions give an independent interest to the study of other lesser-known logics, such as the lattice-based many-valued logics. (shrink)

It is often suggested that we are equipped with a set of cognitive tools that help us to filter out unreliable testimony. But are these tools effective? I answer this question in two steps. Firstly, I argue that they are not real-time effective. The process of filtering, which takes place simultaneously with or right after language comprehension, does not prevent a particular hearer on a particular occasion from forming beliefs based on false testimony. Secondly, I argue that they are (...) long-term effective. Some hearers sometimes detect false testimony, which increases speakers’ incentives for honesty and stabilizes the practice of human communication in which deception is risky and costly. In short, filtering prevents us from forming a large number of beliefs based on false testimony, not by turning each of us into a high-functioning polygraph but by turning the social environment of human communication into one in which such polygraphs are not required. Finally, I argue that these considerations support strong anti-reductionism about testimonial entitlement. (shrink)

We give an affirmative answer to Brendle's and Hrušák's question of whether the club principle together with h > N₁ is consistent. We work with a class of axiom A forcings with countable conditions such that q ≥ n p is determined by finitely many elements in the conditions p and q and that all strengthenings of a condition are subsets, and replace many names by actual sets. There are two types of technique: one for tree-like forcings and one (...) for forcings with creatures that are translated into trees. Both lead to new models of the club principle. (shrink)

It is shown in this paper that it is consistent (relative to almost huge cardinals) for various club guessing ideals to be saturated.

If $\mathcal{F}$ is a filter on $\omega$, we say that $\mathcal{F}$ is Canjar if the corresponding Mathias forcing does not add a dominating real. We prove that any Borel Canjar filter is $F_{\sigma}$, solving a problem of Hrušák and Minami. We give several examples of Canjar and non-Canjar filters; in particular, we construct a $\mathsf{MAD}$ family such that the corresponding Mathias forcing adds a dominating real. This answers a question of Brendle. Then we prove that in all the (...) “classical” models of $\mathsf{ZFC}$ there are $\mathsf{MAD}$ families whose Mathias forcing does not add a dominating real. We also study ideals generated by branches, and we uncover a close relation between Canjar ideals and the selection principle $S_{\mathrm{fin}}$ on subsets of the Cantor space. (shrink)

We explore the problem of constructing maximal and unbounded filters on computable posets. We obtain both computability results and reverse mathematics results. A maximal filter is one that does not extend to a larger filter. We show that every computable poset has a \Delta^0_2 maximal filter, and there is a computable poset with no \Pi^0_1 or \Sigma^0_1 maximal filter. There is a computable poset on which every maximal filter is Turing complete. We obtain the reverse (...) mathematics result that the principle "every countable poset has a maximal filter" is equivalent to ACA₀ over RCA₀. An unbounded filter is a filter which achieves each of its lower bounds in the poset. We show that every computable poset has a \Sigma^0_1 unbounded filter, and there is a computable poset with no \Pi^0_1 unbounded filter. We show that there is a computable poset on which every unbounded filter is Turing complete, and the principle "every countable poset has an unbounded filter" is equivalent to ACA₀ over RCA₀. We obtain additional reverse mathematics results related to extending arbitrary filters to unbounded filters and forming the upward closures of subsets of computable posets. (shrink)

To the French critics who originally labelled certain films noir it seemed that a class of Hollywood products had gone darker during the war years – as though a dark filter had been placed over the lens. Films were not designed or marketed as noir, and retrospectively noir's status as a genre is still unsettled. Yet there is widespread interest today in experiencing diverse films as noir, and even in using a Noir Filter in Instagram and video games. (...) Pursuing the filter clue, the noir experience can be thought of as subjection to a dark filtering of narrative. Image filtering styles can help to resolve not only the puzzle of noir's quasi-genre status but also an issue of general interest in aesthetic experience. The use of image filters makes a distinctively powerful contribution to the experience of a work or genre, or to the cultural dominance of an aesthetic regime, due to the unobtrusive formative role it plays in the economy of experience. (shrink)

Decision-making has a high practical relevance for daily performance. Its relation to other cognitive abilities such as executive control and memory is not fully understood. Here we asked whether training of either attentional filtering or memory storage would influence decision-making as indexed by repetitive assessments of the Iowa Gambling Task (IGT). The IGT was developed to assess and simulate real-life decision-making (Bechara et al., 2005). In this task, participants gain or lose money by developing advantageous or disadvantageous decision strategies. On (...) five consecutive days we trained 29 healthy young adults (20-30 years) either in working memory storage or attentional filtering and measured their IGT scores after each training session. During memory training (MT) subjects performed a computerized delayed match-to-sample task where two displays of bars were presented in succession. During filter training (FT) participants had to indicate whether two simultaneously presented displays of bars matched or not. Whereas in MT the relevant target stimuli stood alone, in FT the targets were embedded within irrelevant distractors (bars in a different color). All subjects within each group improved their performance in the trained cognitive task. For the IGT, we observed an increase over time in the amount of money gained in the FT group only. Decision-making seems to be influenced more by training to filter out irrelevant distractors than by training to store items in working memory. Selective attention could be responsible for the previously noted relationship between IGT performance and working memory and is therefore more important for enhancing efficiency in decision-making. (shrink)

The aim of this chapter is to analyze the movie Fight Club, directed by David Fincher, written by Jim Uhls, and first released in the fall of 1999. The movie is based on the homonym novel by Chuck Palahniuk, published in 1996. I will argue that Fight Club is to be understood in primarily existentialist, nonethical, and nonevidential terms, showing the struggle felt by each and every one of us to find a convincing answer to the question of (...) what (if anything) counts as an authentic life that is worth living. Moreover, I will argue that the movie does not merely illustrate the struggle and the existential angst it engenders; it also advances, if not strictly speaking a theoretical answer grounded in an indisputable philosophical reasoning, then at least a practical way to face it. It is only after positively endorsing the claim that absolutely nothing (whatever it may be) externally imposed on a person can give their life ultimate meaning that a person is free to engage in a conscious, laborious, and exhausting attempt at self-affirmation, a full and positive endorsement of one’s own authenticity. (shrink)

Leibniz filters play a prominent role in the theory of protoalgebraic logics. In [3] the problem of the definability of Leibniz filters is considered. Here we study the definability of Leibniz filters with parameters. The main result of the paper says that a protoalgebraic logic S has its strong version weakly algebraizable iff it has its Leibniz filters explicitly definable with parameters.

This article explores what John Dewey’s political philosophy can offer in regard to the current crisis in digital democracy. It focuses on two digital mechanisms, the “filter bubble” and the “echo chamber”. While there is a prominent, Dewey-inspired debate on “digital publics” in the literature, a reconstruction of the Deweyan concepts of the public and of shared experience shows that it does not adequately reflect the aspect of situated and embodied experience. Based on this, it is shown that digital (...) media offerings must also be rooted in local contexts of experience in order to answer the challenge of those two problematic mechanisms. (shrink)

We characterize (both from a syntactic and an algebraic point of view) the normal K4-logics for which unification is filtering. We also give a sufficient semantic criterion for existence of most general unifiers, covering natural extensions of K4.2⁺ (i.e., of the modal system obtained from K4 by adding to it, as a further axiom schemata, the modal translation of the weak excluded middle principle).

The present paper is thought as a formal study of distributive closure systems which arise in the domain of sentential logics. Special stress is laid on the notion of a C-filter, playing the role analogous to that of a congruence in universal algebra. A sentential logic C is called filter distributive if the lattice of C-filters in every algebra similar to the language of C is distributive. Theorem IV.2 in Section IV gives a method of axiomatization of those (...) filter distributive logics for which the class Matr (C) prime of C-prime matrices (models) is axiomatizable. In Section V, the attention is focused on axiomatic strengthenings of filter distributive logics. The theorems placed there may be regarded, to some extent, as the matrix counterparts of Baker's well-known theorem from universal algebra [9, § 62, Theorem 2]. (shrink)

Resumo Visto por uma lente existencial, o filme Fight Club impele-nos a criar um autêntico self. Porém, também nos adverte que a criação de um autêntico self é algo que só podemos fazer por nós mesmos. A definitiva ironia no filme Fight Club é que, num esforço por rejeitar a sociedade e cultivar a individualidade, as pessoas acabam por se conformar a um culto e aos seus ditames. A lição é que a autenticidade é frágil, facilmente esmagada e (...) facilmente rendida. No final do filme, o protagonista, oferece-nos esperança, ainda que seja para nos tornarmos auto-conscientes e lutar contra as forças que nos procuram subjugar. Palavras-chave : autenticidade, consumismo, existencialismo, Fight Club, Nietzsche, vícioViewed through an existential lens, Fight Club urges us to create an authentic self, but it also cautions us that the creation of an authentic self is something we can only do for ourselves. The ultimate irony in Fight Club is that in an effort to reject society and cultivate individuality, people end up conforming to a cult and its dictates. The clear lesson is that authenticity is fragile, easily crushed and easily surrendered. By the end of the movie, the protagonist at least offers us hope, though, that we can become self-aware and fight back against the forces that seek to subjugate us. Keywords : addiction, authenticity, consumerism, existentialism, Fight Club, Nietzsche. (shrink)

With the use of a suitable assumption about the structure of the class of experimental filters, it is shown that the sequence of alternating replicas of two filters is their greatest lower bound, as Jauch suggests. A generalization of his suggestion yields the greatest lower bound of a denumerable set of filters. The criteria of admissibility of filters are briefly discussed.

In this paper we introduce the notion of filter on the neutrosophic crisp set, then we consider a generalization of the filter’s studies. Afterwards, we present the important neutrosophic crisp filters. We also study several relations between different neutrosophic crisp filters and neutrosophic topologies. Possible applications to database systems are touched upon.

Two countable filters on $\omega$ are incompatible if they have no common infinite pseudointersection. Letting $\alpha(P_f)$ denote the minimal size of a maximal uncountable family of pairwise incompatible countable filters on $\omega$, we prove the consistency of t $< \alpha(P_f)$.

I argue that classical counterfactual semantics in the style of Stalnaker, Lewis, and Kratzer validates an inference pattern that is disconfirmed in natural language. The solution is to alter the algorithm we use to handle inconsistency in premise sets: rather than checking all maximally consistent fragments of a premise sets, as in Krazter’s semantics, we selectively remove some of the premises. The proposed implementation starts from standard premise semantics and involves a new ‘filtering’ operation that achieves just this removal. The (...) resulting semantics is interestingly related to the semantics for counterfactuals emerging from Judea Pearl’s causal models framework in computer science: in particular, filtering is a possible worlds semantics counterpart of Pearl’s interventions. (shrink)

It is commonly assumed that personalization technologies used by Google for the purpose of tailoring search results for individual users create filter bubbles, which reinforce users’ political views. Surprisingly, empirical evidence for a personalization-induced filter bubble has not been forthcoming. Here, we investigate whether filter bubbles may result instead from a searcher’s choice of search queries. In the first experiment, participants rated the left-right leaning of 48 queries (search strings), 6 for each of 8 topics (abortion, benefits, (...) climate change, sex equality, immigration, nuclear family, Islam, and taxation). An independent sample of participants were then asked to select one of these queries for each of the 8 topics. With the exception of the topic of Islam, participants were significantly more likely to select a query corresponding to their own political leaning, compared to other queries, explaining between 12% and 39% of the variance. A second experiment investigated the effect of the political leaning of the same queries on the overall political leaning of Search Engine Result Pages (SERPs) in Google Search. The top six results of each SERP were rated collectively by a third group of participants, explaining 36.3% of the variance across all 48 search terms (p < .00001). That is, (1) participants in our experiments tended to select own-side search queries, and (2) using those queries tended to yield own-side search results when using the Google search engine. Our results are consistent with the notion of a self-imposed filter bubble in which query selection plays a salient role. (shrink)

Online information intermediaries such as Facebook and Google are slowly replacing traditional media channels thereby partly becoming the gatekeepers of our society. To deal with the growing amount of information on the social web and the burden it brings on the average user, these gatekeepers recently started to introduce personalization features, algorithms that filter information per individual. In this paper we show that these online services that filter information are not merely algorithms. Humans not only affect the design (...) of the algorithms, but they also can manually influence the filtering process even when the algorithm is operational. We further analyze filtering processes in detail, show how personalization connects to other filtering techniques, and show that both human and technical biases are present in today’s emergent gatekeepers. We use the existing literature on gatekeeping and search engine bias and provide a model of algorithmic gatekeeping. (shrink)

We outline the proof of the consistency that there exists a saturated tail club guessing ideal on ω₁ which is not a restriction of the nonstationary ideal. A new class of forcing notions and the forcing axiom for the class are introduced for this purpose.

We propose a model of uncertain belief. This models coherent beliefs by a filter, ????, on the set of probabilities. That is, it is given by a collection of sets of probabilities which are closed under supersets and finite intersections. This can naturally capture your probabilistic judgements. When you think that it is more likely to be sunny than rainy, we have{????|????(????????????????????)>????(????????????????????)}∈????. When you think that a gamble ???? is desirable, we have {????|Exp????[????]>0}∈????. It naturally extends the model of (...) credal sets; and we will show it captures all the expressive power of the desirable gambles model. It also captures the expressive power of sets of desirable gamble sets (with a mixing axiom, but no Archimadean axiom). (shrink)

Advances in artificial intelligence, as well as its increased presence in everyday life, have brought the emergence of many new phenomena, including an intriguing appearance of what seems to be a variant of body dysmorphic disorder, coined “Snapchat dysmorphia”. Body dysmorphic disorder is a DSM-5 psychiatric disorder defined as a preoccupation with one or more perceived defects or flaws in physical appearance that are not observable or appear slight to others. Snapchat dysmorphia is fueled by automated selfie filters that reflect (...) unrealistic sociocultural standard. In this paper, we discuss how body dysmorphic disorder and related body image distortions could arise, using the conceptual resources provided by the active inference framework. We suggest that these disorders involve dysfunctional self-modelling which entails maladaptive internalization of sociocultural preferences during adolescent identity formation. Identity formation is hereby described as cycles of interpersonal active inference that arbitrate between identity exploration and commitment. We propose that impaired self-modelling is unable to reduce interpersonal uncertainty during identity exploration, which, over time, degenerates into uncontrollable epistemic habits that isolate the body image from corrective sensory evidence. In light of these insights, we subsequently explore some of the consequences of image-centered social media platforms on the identity formation process. We conclude that heightened interpersonal uncertainty in this novel context could precipitate the onset of body dysmorphic disorder and related body image distortions, particularly when selfie filters are involved. (shrink)

In Neal Stephenson’s fictional novel, Diamond Age (1995), the protagonist Nell acquires a prototype of what we might today recognise as a highly sophisticated e-reader with a voice-assistant. This e-reader, the “Young Lady’s Illustrated Primer”, uses artificial intelli- gence to serve as Nell’s personal teacher. What is key to the Primer is how it is designed to respond to Nell. The Primer has a theory of Nell – her needs, her real-world situation, her abilities – and it tailors its lessons (...) for her. The Primer is a highly personalised artificially intelligent device. For many readers – myself included – the Primer was a utopian vision of the bespoke digital tutors of the future. The appearance of new media and technologies in the early 2000s all pointed to the near-term reality of devices like Primers. The real-life experience of personalised digital media, though, is so far from Stephen- son’s vision that it is hard to imagine we will ever get there. Nell’s time with the Primer develops her intellectually, emotionally, and physically. Our “bespoke” media experience, by contrast, is more likely to turn us in on ourselves rather than guide us to live well in our societies. Personalised media is making us more like Narcissus: our consumption is driven by personal choices and automated algorithms that reflect what we already want to hear, see, and consume, and we are captivated. Central to our understanding of the problems with the personalisation of digital media are filter bubbles and echo chambers. These phenomena are used interchangeably by some, but in distinct ways by others. I take the position that filter bubbles and echo chambers are distinct phenomena, but ones that raise similar epistemic worries. I begin with a general discussion of filter bubbles and echo chambers, and I introduce the concept of “selective exposure” as central to both phenomena. There is minimal uniformity across uses of the terms “filter bubble” and “echo chamber”. Consequently, I divide the later discussion into two more precise topics: homophily and polarisation. I conclude with some future-looking comments about responsibility and the epistemic risks posed by digital personalisation. (shrink)