Fake news sharing in 2016 was rare but significantly more common among older Americans. So-called “fake news” has renewed concerns about the prevalence and effects of misinformation in political campaigns. Given the potential for widespread dissemination of this material, we examine the individual-level characteristics associated with sharing false articles during the 2016 U.S. presidential campaign. To do so, we uniquely link an original survey with respondents’ sharing activity as recorded in Facebook profile data. First and foremost, we find that sharing (...) this content was a relatively rare activity. Conservatives were more likely to share articles from fake news domains, which in 2016 were largely pro-Trump in orientation, than liberals or moderates. We also find a strong age effect, which persists after controlling for partisanship and ideology: On average, users over 65 shared nearly seven times as many articles from fake news domains as the youngest age group. (shrink)

Larry Barnes, Executive Director of the Southwest Missouri Baptist Association (SMBA), received a telephone call that no executive wants to receive. The pastor at Hilltop Baptist Church reported suspicions of embezzlement by the church bookkeeper. Whatever decision Barnes made in advising the pastor would impact Hilltop, the church members, the SMBA, and a number of stakeholders, including himself. His primary duty as Executive Director was to provide guidance and advice to pastors of SMBA churches, help them expand, and assist in (...) establishing new churches. However, did his professional responsibilities encompass this situation? If not, did he have an ethical obligation to help? What if his involvement caused legal and financial problems for the SMBA? What was the likelihood the bookkeeper and her family might sue the SMBA and Barnes? Many Hilltop Church members were personal friends of Barnes. He worried about jeopardizing hisfriendship with them, particularly if the accusations were incorrect. An equally important concern was whether Hilltop Church would continue to exist. Financial problems had plagued the church in recent years and the relationship between the pastor and members was already contentious. An embezzlement scandal could cause the 150 year old church to close its doors. Barnes had to decide whether to get involved and, if so, what to recommend as a course of action to Hilltop’s pastor. (shrink)

Researchers of advanced technologies are constantly seeking new ways of measuring and adapting to user performance. Appropriately adapting system feedback requires accurate assessments of user performance. Unfortunately, many assessment algorithms must be trained on and use pre‐prepared data sets or corpora to provide a sufficiently accurate portrayal of user knowledge and behavior. However, if the targeted content of the tutoring system changes depending on the situation, the assessment algorithms must be sufficiently independent to apply to untrained content. Such is the (...) case for Interactive Strategy Training for Active Reading and Thinking (iSTART), an intelligent tutoring system that assesses the cognitive complexity of strategy use while a reader self‐explains a text. iSTART is designed so that teachers and researchers may add their own (new) texts into the system. The current paper explores student self‐explanations from newly added texts (which iSTART had not been trained on) and focuses on evaluating the iSTART assessment algorithm by comparing it to human ratings of the students’ self‐explanations. (shrink)

This paper defends the view, put roughly, that to think that p is to guess that p is the answer to the question at hand, and that to think that p rationally is for one’s guess to that question to be in a certain sense non-arbitrary. Some theses that will be argued for along the way include: that thinking is question-sensitive and, correspondingly, that ‘thinks’ is context-sensitive; that it can be rational to think that p while having arbitrarily low credence (...) that p; that, nonetheless, rational thinking is closed under entailment; that thinking does not supervene on credence; and that in many cases what one thinks on certain matters is, in a very literal sense, a choice. Finally, since there are strong reasons to believe that thinking just is believing, there are strong reasons to think that all this goes for belief as well. (shrink)

This paper is about guessing: how people respond to a question when they aren’t certain of the answer. Guesses show surprising and systematic patterns that the most obvious theories don’t explain. We argue that these patterns reveal that people aim to optimize a tradeoff between accuracy and informativity when forming their guess. After spelling out our theory, we use it to argue that guessing plays a central role in our cognitive lives. In particular, our account of guessing (...) yields new theories of belief, assertion, and the conjunction fallacy—the psychological finding that people sometimes rank a conjunction as more probable than one of its conjuncts. More generally, we suggest that guessing helps explain how boundedly rational agents like us navigate a complex, uncertain world. (shrink)

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.

Guessing is a familiar activity, one we engage in when we are uncertain of the answer to a question under discussion. It is also an activity that lends itself to normative evaluation: some guesses are better than others. The question that interests me here is what makes for a good guess. In recent work, Dorst and Mandelkern have argued that good guesses are distinguished from bad ones by how well they optimize a tradeoff between accuracy and specificity. Here I (...) argue that Dorst and Mandelkern’s implementation of this idea fails to satisfy some plausible constraints on good guesses, and I develop an alternative implementation that satisfies the relevant constraints. The result is a new account of good guesses which retains the positive aspects of Dorst and Mandelkern’s proposal, but without the drawbacks. (shrink)

L. Jonathan Cohen; XI*—Guessing, Proceedings of the Aristotelian Society, Volume 74, Issue 1, 1 June 1974, Pages 189–210, https://doi.org/10.1093/aristotelian/7.

From the author of Quantum Mechanics and Experience, a hugely influential book that challenged key assertions by Niels Bohr and other founders of quantum mechanics, A Guess at the Riddle provides a major metaphysical overhaul of one of physics' most intractable problems-the quest to bridge quantum and classical physics in order to understand the nature of reality.

Credences, unlike full beliefs, can’t be true or false. So what makes credences more or less accurate? This chapter offers a new answer to this question: credences are accurate insofar as they license true educated guesses, and less accurate insofar as they license false educated guesses. This account is compatible with immodesty; : a rational agent will regard her own credences to be best for the purposes of making true educated guesses. The guessing account can also be used to (...) justify certain coherence constraints on rational credence, such as probabilism. The chapter concludes by discussing some advantages of the guessing account over rival accounts of accuracy. (shrink)

It has recently become popular to analyze scenarios in which we guess, in terms of a trade‐off between the accuracy of our guess (namely, its credence) and its specificity (namely, how many answers it rules out). Dorst and Mandelkern describe an account of guessing, based on epistemic utility theory (EUT), in which permissible guesses vary depending on how one weighs accuracy against specificity. We provide a minimal formal account of guessing that: (i) does not employ EUT, but rests (...) on how such trade‐offs are treated in the sciences; (ii) is relatively parsimonious; and (iii) is consistent with a variety of more specific models that describe what an agent is doing when they (rationally) guess. Our account also recovers patterns of guessing and predictions about typical outcomes of guessing, as identified by Dorst and Mandelkern. Furthermore, we focus on how permissible guesses can be improved upon, via changes in an agent's credence distribution. Such better permissible guesses can be generated in solving Fermi problems—guessing problems of a type that has received almost no attention in the philosophical literature—which we also analyze. Our account strengthens the case for understanding guessing (now, very broadly considered) in terms of accuracy‐specificity trade‐offs. (shrink)

Light and Kennison found that bias effects in the forced-choice perceptual identification of words occurred only in a subset of participants, those who claimed on a strategy questionnaire to be deliberately guessing words they had studied previously. McKoon and Ratcliff raised a number of objections to the proposal that bias effects are due to guessing strategies, citing difficulties in our statistical treatment of data, our use of subjective reports to classify participants, and our approach to the general problem (...) of separating implicit from explicit influences on performance. This article responds to these objections. (shrink)

Ian Hacking; III—Guessing by Frequency, Proceedings of the Aristotelian Society, Volume 64, Issue 1, 1 June 1964, Pages 55–70, https://doi.org/10.1093/aristotel.

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

Of the scientific concepts that the American philosopher, Charles S. Peirce, analyzed in his work, two of the less commonly investigated have been those of guessing and of scientific economy. Peirce argued that guessing was the initial moment of hypothesis-formation. He also argued that economic factors play a significant role in the development and acceptance of hypotheses; however, the relationship between these two concepts has been neglected in most philosophical and scientific literature. In the following, I provide an (...) analysis of how guessing and economic considerations contribute to hypothesis-formation. This analysis focuses primarily upon medical science; specifically, the epidemiology of HIV/AIDS. By using the first case studies in medical research that led to the ‘discovery’ of HIV/AIDS, I will argue that guessing is a tool utilized by researchers that is determined, at least in part, by implicit bias and economic considerations, which ultimately effect the trajectory of hypothesis-formation and the ensuing scientific research founded upon those hypotheses. In this particular case, both the biases of researchers and their effect upon economic considerations in the initial moments of guessing led to problematic hypotheses concerning the disease, populations susceptible to the disease, and how it was transmitted within that population. By recognizing how guessing and economy relate in this particular case and the functions of these conceptual tools as they relate to the isolation and discovery of disease, we can better understand epidemiological investigations and facilitate overcoming detrimental biases in such investigations. (shrink)

We analyze the notion of guessing model, a way to assign combinatorial properties to arbitrary regular cardinals. Guessing models can be used, in combination with inaccessibility, to characterize various large cardinal axioms, ranging from supercompactness to rank-to-rank embeddings. The majority of these large cardinal properties can be defined in terms of suitable elementary embeddings j:Vγ→Vλ. One key observation is that such embeddings are uniquely determined by the image structures j[Vγ]≺Vλ. These structures will be the prototypes guessing models. (...) We shall show, using guessing models M, how to prove for the ordinal κM=jM) many of the combinatorial properties that we can prove for the cardinal j) using the structure j[Vγ]≺Vj. κM will always be a regular cardinal, but consistently can be a successor and guessing models M with κM=ℵ2 exist assuming the proper forcing axiom. By means of these models we shall introduce a new structural property of models of PFA: the existence of a “Laver function” f:ℵ2→Hℵ2 sharing the same features of the usual Laver functions f:κ→Hκ provided by a supercompact cardinal κ. Further applications of our analysis will be proofs of the singular cardinal hypothesis and of the failure of the square principle assuming the existence of guessing models. In particular the failure of square shows that the existence of guessing models is a very strong assumption in terms of large cardinal strength. (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.

I develop a general framework with a rationality constraint that shows how coherently to represent and deal with second-order information about one's own judgmental reliability. It is a rejection of and generalization away from the typical Bayesian requirements of unconditional judgmental self-respect and perfect knowledge of one's own beliefs, and is defended by appeal to the Principal Principle. This yields consequences about maintaining unity of the self, about symmetries and asymmetries between the first- and third-person, and a principled way of (...) knowing when to stop second-guessing oneself. Peer disagreement is treated as a special case where one doubts oneself because of news that an intellectual equal disagrees. This framework, and variants of it, imply that the typically stated belief that an equally reliably peer disagrees is incoherent, and thus that pure rationality constraints without further substantive information cannot give an answer as to what to do. The framework also shows that treating both ourselves and others as thermometers in the disagreement situation does not imply the Equal Weight view. (shrink)

This paper theoretically and experimentally investigates the behavior of asymmetric players in guessing games. The asymmetry is created by introducing r>1\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$r>1$$\end{document} replicas of one of the players. Two-player and restricted N-player cases are examined in detail. Based on the model parameters, the equilibrium is either unique in which all players choose zero or mixed in which the weak player (r=1\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$r=1$$\end{document}) imitates the (...) strong player (r>1\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$r>1$$\end{document}). A series of experiments involving two and three-player repeated guessing games with unique equilibrium is conducted. We find that equilibrium behavior is observed less frequently and overall choices are farther from the equilibrium in two-player asymmetric games in contrast to symmetric games, but this is not the case in three-player games. Convergence towards equilibrium exists in all cases but asymmetry slows down the speed of convergence to the equilibrium in two, but not in three-player games. Furthermore, the strong players have a slight earning advantage over the weak players, and asymmetry increases the discrepancy in choices (defined as the squared distance of choices from the winning number) in both games. (shrink)

König, Larson and Yoshinobu initiated the study of principles for guessing generalized clubs, and introduced a construction of a higher Souslin tree from the strong guessing principle.Complementary to the author’s work on the validity of diamond and non-saturation at the successor of singulars, we deal here with a successor of regulars. It is established that even the non-strong guessing principle entails non-saturation, and that, assuming the necessary cardinal arithmetic configuration, entails a diamond-type principle which suffices for the (...) construction of a higher Souslin tree.We also establish the consistency of GCH with the failure of the weakest form of generalized club guessing. This, in particular, settles a question from the original paper. (shrink)

In the typical single-stimulus perceptual identification task, accuracy is improved by prior study of test words, a repetition priming benefit. There is also a cost, inasmuch as previously studied words are likely to be produced as responses if the test word is orthographically similar but not identical to a studied word. In two-alternative forced-choice perceptual identification, a test word is flashed and followed by two alternatives, one of which is the correct response. When the two alternatives are orthographically similar, test (...) words identical to previously studied items are identified more accurately than new words but tests words orthographically similar to studied words are identified less accurately than new words . Ratcliff and McKoon argue that these are bias effects that arise in the decision stage of word identification. We report five experiments that examined the alternative hypothesis that these bias effects arise from postperceptual guessing strategies. In single-stimulus perceptual identification, repetition priming benefits were equally great for young and older adults who claimed to use deliberate guessing strategies and those who did not . In contrast, only groups of young and older people who claimed to deliberately guess studied words in a two-alternative forced-choice task showed reliable benefits and costs. Costs and benefits were abolished in the two-alternative forced-choice task when a very long study list was used, presumably because the increased retrieval burden made the use of deliberate guessing strategies less attractive . Under conditions similar to those of Experiment 3, repetition priming was observed in single-stimulus perceptual identification . These results are consistent with the view that costs and benefits in the forced-choice perceptual identification task arise from deliberate guessing strategies but that those in the single-stimulus task do not. The possibility that the observed relationship between strategy reports and priming effects reflects erroneous postexperimental assessments of strategies by participants is also considered. (shrink)

In his dissertation, Wadge defined a notion of guessability on subsets of the Baire space and gave two characterizations of guessable sets. A set is guessable if and only if it is in the second ambiguous class, if and only if it is eventually annihilated by a certain remainder. We simplify this remainder and give a new proof of the latter equivalence. We then introduce a notion of guessing with an ordinal limit on how often one can change one’s (...) mind. We show that for every ordinal $\alpha$, a guessable set is annihilated by $\alpha$ applications of the simplified remainder if and only if it is guessable with fewer than $\alpha$ mind changes. We use guessability with fewer than $\alpha$ mind changes to give a semi-characterization of the Hausdorff difference hierarchy, and indicate how Wadge’s notion of guessability can be generalized to higher-order guessability, providing characterizations of ${\mathbf{\Delta}}^{0}_{\alpha}$ for all successor ordinals $\alpha\gt 1$. (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.

"Sheriff’s text moves the "guess" to a new level of understanding, while integrating much of Peirce’s philosophy, and provokes many questions." —Society for the Advancement of American Philosophy Newletter "The purpose of Sheriff’s work is to expound Peirce’s unified theory of the universe—from cosmology to semiotic—and to discuss its ramifications for how we should live. He concludes that Peirce has given us a theory we can live with. The book makes an important contribution to philosophy of life and to the (...) humanities in general."—Nathan Houser "In clear and concise prose, Sheriff describes Peirce’s ‘theory of everything,’ a vision of cosmic and human meaning that offers a positive alternative to popular pessimistic and relativistic approaches to life and meaning." —Peirce Project Newsletter. (shrink)

According to Karl Popper, the evolution of science, logically, methodologically, and even psychologically, is an involved interplay of acute conjectures and blunt refutations. Like biological evolution, it is an endless round of blind variation and selective retention. But unlike biological evolution, it incorporates, at the stage of selection, the use of reason. Part I of this two-part paper begins by repudiating the common beliefs that Hume’s problem of induction, which compellingly confutes the thesis that science is rational in the way (...) that most people think that it is rational, can be solved by assuming that science is rational, or by assuming that Hume was irrational (that is, by ignoring his argument). The problem of induction can be solved only by a non-authoritarian theory of rationality. It is shown also that because hypotheses cannot be distilled directly from experience, all knowledge is eventually dependent on blind conjecture, and therefore itself conjectural. In particular, the use of rules of inference, or of good or bad rules for generating conjectures, is conjectural. Part II of the paper expounds a form of Popper’s critical rationalism that locates the rationality of science entirely in the deductive processes by which conjectures are criticized and improved. But extreme forms of deductivism are rejected. The paper concludes with a sharp dismissal of the view that work in artificial intelligence, including the JSM method cultivated extensively by Victor Finn, does anything to upset critical rationalism. Machine learning sheds little light on either the problem of induction or on the role that logic plays in the development of scientific knowledge. (shrink)

As the world keeps advancing, the need for automated interconnected devices has started to gain significance; to cater to the condition, a new concept Internet of Things has been introduced that revolves around smart devicesʼ conception. These smart devices using IoT can communicate with each other through a network to attain particular objectives, i.e., automation and intelligent decision making. IoT has enabled the users to divide their household burden with machines as these complex machines look after the environment variables and (...) control their behavior accordingly. As evident, these machines use sensors to collect vital information, which is then the complexity analyzed at a computational node that then smartly controls these devicesʼ operational behaviors. Deep learning-based guessing attack protection algorithms have been enhancing IoT security; however, it still has a critical challenge for the complex industries’ IoT networks. One of the crucial aspects of such systems is the need to have a significant training time for processing a large dataset from the networkʼs previous flow of data. Traditional deep learning approaches include decision trees, logistic regression, and support vector machines. However, it is essential to note that this convenience comes with a price that involves security vulnerabilities as IoT networks are prone to be interfered with by hackers who can access the sensor/communication data and later utilize it for malicious purposes. This paper presents the experimental study of cryptographic algorithms to classify the types of encryption algorithms into the asymmetric and asymmetric encryption algorithm. It presents a deep analysis of AES, DES, 3DES, RSA, and Blowfish based on timing complexity, size, encryption, and decryption performances. It has been assessed in terms of the guessing attack in real-time deep learning complex IoT applications. The assessment has been done using the simulation approach and it has been tested the speed of encryption and decryption of the selected encryption algorithms. For each encryption and decryption, the tests executed the same encryption using the same plaintext for five separate times, and the average time is compared. The key size used for each encryption algorithm is the maximum bytes the cipher can allow. To the comparison, the average time required to compute the algorithm by the three devices is used. For the experimental test, a set of plaintexts is used in the simulation—password-sized text and paragraph-sized text—that achieves target fair results compared to the existing algorithms in real-time deep learning networks for IoT applications. (shrink)

“Scientific research faces up with an open and unknown world”Within the work of C. S. Peirce, the most fundamental and contentious form of inference is that of abduction. According to Peirce, abduction is the only type of inference from which new ideas are created (CP 5.171, 1903). He wrote, “every single item of scientific theory which stands established today has been due to Abduction” (CP 5.172, 1903). Similarly, “All that makes knowledge applicable comes to us viâ abduction. […] Not the (...) smallest advance can be made in knowledge beyond the stage of vacant staring, without making an abduction at every step” (HP 2:899–900, 1901). It is little wonder that so much attention has been paid to this particular type of.. (shrink)

Club guessing principles were introduced by Shelah as a weakening of Jensen’s diamond. Most spectacularly, they were used to prove Shelah’s $\textsf{ZFC}$ bound on $2^{\aleph _\omega }$. These principles have found many other applications: in cardinal arithmetic and PCF theory; in the construction of combinatorial objects on uncountable cardinals such as Jónsson algebras, strong colourings, Souslin trees, and pathological graphs; to the non-existence of universals in model theory; to the non-existence of forcing axioms at higher uncountable cardinals; and many (...) more.In this paper, the first part of a series, we survey various forms of club guessing that have appeared in the literature, and then systematically study the various ways in which a club guessing sequence can be improved, especially in the way the frequency of guessing is calibrated.We include an expository section intended for those unfamiliar with club guessing and which can be read independently of the rest of the article. (shrink)

Popper's methodology does not entail any playing down of the various indispensible distinctions such as the distinction between knowing and guessing, the distinction between myth and science, the distinction between the observational and the theoretical, and between the vernacular and technical sublanguages or technical vocabulary. By avoiding both the totalization that led to the foundationalist position and the scepticist reactions to these frustrated foundationalist hopes, Popper's methodology makes it possible to combine fallibilism with a realist view of theories. It (...) combines the perennial willingness to re-examine positions, statements, etc. with the claim that a particular theory (as an item of knowledge in the objective sense) constitutes cognitive progress over its rivals. However, some of his formulations have been deliberately provocative and in this way have given rise to certain misgivings about possible paradoxical implications, even in philosophers congenial with Popper's approach. The concept of knowledge in the objective sense is, of course, an explicatum which Popper proposes primarily for use in methodology and epistemology. The concept is an expression of the acknowledgment of fallibility in principle. The phrasing that ‘knowledge is conjectural’ or ‘knowledge is fallible’, even when it refers to knowledge in the objective sense, is but an abbreviation for: since our methods for ascertaining the truth-value of a particular statement about empirical reality are fallible in principle, there cannot be any certain knowledge about reality. In everyday life and in politics tolerance will be possible to the extent to which the recognition of this fallibility is more than a declaration. (shrink)

A survey of 172 undergraduates, carried out during the fall 2002 and spring 2003 semesters at a large research university in the Midwestern United States, found, as expected, a statistically significant positive relationship between the importance students attributed to attendance and the rates at which they subsequently attended class. Data are analysed by students’ gender and levels in school; and attendance rates of students who did not complete the optional survey question on attitudes are compared with attendance rates of students (...) who answered the question. Although attitudes are but one of many complex factors that influence behaviours, university instructors can nurture and encourage positive attitudes towards the importance of class attendance as a means for minimizing the detrimental effects of student absences. (shrink)

The article examines and extends work bringing together engineering ethics and Science and Technology Studies, which had built upon Diane Vaughan’s analysis of the Challenger shuttle accident as a test case. Reconsidering the use of her term “normalization of deviance,” the article argues for a middle path between moralizing against and excusing away engineering practices contributing to engineering disaster. To explore an illustrative pedagogical case and to suggest avenues for constructive research developing this middle path, it examines the emergence of (...) green chemistry and green engineering. Green chemistry began when Paul Anastas and John Warner developed a set of new rules for chemical synthesis that sought to learn from missed opportunities to avoid environmental damage in the twentieth century, an approach that was soon extended to engineering as well. Examination of tacit assumptions about historical counterfactuals in recent, interdisciplinary discussions of green chemistry illuminate competing views about the field’s prospects. An integrated perspective is sought, addressing how both technical practice within chemistry and engineering and the influence of a wider “social movement” can play a role in remedying environmental problems. (shrink)

In “An ‘Entirely Different Series of Categories,’” I argue that aside from Peirce’s formal categories of Firstness, Secondness, and Thirdness, Peirceans should acknowledge a second set of categories I call the material categories. I also argue that the material categories are irreducible to the formal categories. However, in that article I offer no account of what the material categories are. Moreover, Peirce himself never provides a clear and explicit account of them. The present essay attempts to provide an account of (...) the Peircean material categories. Like Peirce’s “Guess at the Riddle,” which sought to elucidate his formal categories, this is a guess at the other riddle, his material categories, with.. (shrink)

We obtain very strong coloring theorems at successors of singular cardinals from failures of certain instances of simultaneous reflection of stationary sets. In particular, the simplest of our results establishes that if μ is singular and , then there is a regular cardinal θ<μ such that any fewer than cf stationary subsets of must reflect simultaneously.

In this explosive book, Howard Wainer uses statistical evidence to show why some of the most widely held beliefs in education today--and the policies that have resulted--are wrong.

It is possible to control to a large extent, via semiproper forcing, the parameters measuring the guessing density of the members of any given antichain of stationary subsets of ω1 . Here, given a pair of ordinals, we will say that a stationary set Sω1 has guessing density if β0=γ and , where γ is, for every stationary S*ω1, the infimum of the set of ordinals τ≤ω1+1 for which there is a function with ot)<τ for all νS* and (...) with {νS*:gF} stationary for every α<ω2 and every canonical function g for α. This work involves an analysis of iterations of models of set theory relative to sequences of measures on possibly distinct measurable cardinals. As an application of these techniques I show how to force, from the existence of a supercompact cardinal, a model of in which there is a well-order of H definable, over H,, by a formula without parameters. (shrink)

This paper considers a central objection to evolutionary epistemology. The objection is that biological and epistemic development are not analogous, since while biological variation is blind, epistemic variation is not. The generation of hypotheses, unlike the generation of genotypes, is not random. We argue that this objection is misguided and show how the central analogy of evolutionary epistemology can be preserved. The core of our reply is that much epistemic variation is indeed directed by heuristics, but these heuristics are analogous (...) to biological preadaptations which account for the evolution of complex organs. We also argue that many of these heuristics or epistemic preadaptations are not innate but were themselves generatedby a process of blind variation and selective retention. (shrink)