laudationem ferculum est insecutum plane non pro expectatione magnum: novitas tamen omnium convertit oculos. rotundum enim repositoriurr duodecim habebat signa in orbe disposita, super quae proprium convenien. temque materiae structor imposuerat cibum: super arietem cicer arietinum, super taurum bubulae frustum, super geminos testiculos ac rienes, supei cancrum coronam, super leonem ficum Africanam, super virginem steriliculam super libram stateram in cuius altera parte scriblita erat, in altera placenta super scorpionem † pisciculum marinum, super sagittarium oclopetam, supei capricornum locustam marinam,† super pisces (...) duos mullos. in medio autem caespes cum herbis excisus favum sustinebat. (shrink)

laudationem ferculum est insecutum plane non pro expectatione magnum: novitas tamen omnium convertit oculos. rotundum enim repositoriurr duodecim habebat signa in orbe disposita, super quae proprium convenien. temque materiae structor imposuerat cibum: super arietem cicer arietinum, super taurum bubulae frustum, super geminos testiculos ac rienes, supei cancrum coronam, super leonem ficum Africanam, super virginem steriliculam super libram stateram in cuius altera parte scriblita erat, in altera placenta super scorpionem † pisciculum marinum, super sagittarium oclopetam, supei capricornum locustam marinam,† super pisces (...) duos mullos. in medio autem caespes cum herbis excisus favum sustinebat. (shrink)

It is often assumed that engaging in a one‐on‐one dialogue with a tutor is more effective than listening to a lecture or reading a text. Although earlier experiments have not always supported this hypothesis, this may be due in part to allowing the tutors to cover different content than the noninteractive instruction. In 7 experiments, we tested the interaction hypothesis under the constraint that (a) all students covered the same content during instruction, (b) the task domain was qualitative physics, (c) (...) the instruction was in natural language as opposed to mathematical or other formal languages, and (d) the instruction conformed with a widely observed pattern in human tutoring: Graesser, Person, and Magliano's 5‐step frame. In the experiments, we compared 2 kinds of human tutoring (spoken and computer mediated) with 2 kinds of natural‐language‐based computer tutoring (Why2‐Atlas and Why2‐AutoTutor) and 3 control conditions that involved studying texts. The results depended on whether the students' preparation matched the content of the instruction. When novices (students who had not taken college physics) studied content that was written for intermediates (students who had taken college physics), then tutorial dialogue was reliably more beneficial than less interactive instruction, with large effect sizes. When novices studied material written for novices or intermediates studied material written for intermediates, then tutorial dialogue was not reliably more effective than the text‐based control conditions. (shrink)

It is often assumed that engaging in a one‐on‐one dialogue with a tutor is more effective than listening to a lecture or reading a text. Although earlier experiments have not always supported this hypothesis, this may be due in part to allowing the tutors to cover different content than the noninteractive instruction. In 7 experiments, we tested the interaction hypothesis under the constraint that (a) all students covered the same content during instruction, (b) the task domain was qualitative physics, (c) (...) the instruction was in natural language as opposed to mathematical or other formal languages, and (d) the instruction conformed with a widely observed pattern in human tutoring: Graesser, Person, and Magliano's 5‐step frame. In the experiments, we compared 2 kinds of human tutoring (spoken and computer mediated) with 2 kinds of natural‐language‐based computer tutoring (Why2‐Atlas and Why2‐AutoTutor) and 3 control conditions that involved studying texts. The results depended on whether the students' preparation matched the content of the instruction. When novices (students who had not taken college physics) studied content that was written for intermediates (students who had taken college physics), then tutorial dialogue was reliably more beneficial than less interactive instruction, with large effect sizes. When novices studied material written for novices or intermediates studied material written for intermediates, then tutorial dialogue was not reliably more effective than the text‐based control conditions. (shrink)

The career of the father of Claudius Etruscus is of special importance in the history of the Imperial administration in the first century A.D. In the course of a long life he rose from slave status under Tiberius to be head of the Imperial financial administration and to equestrian status under Vespasian. He was one of the most important, wealthy, and influential of the Imperial freedmen in the first century when their influence was at its peak; he is one of (...) the best documented of their number outside the pages of Tacitus; yet we do not know his personal name—he has to remain simply ‘the father of Claudius Etruscus’ —and even his nomen gentilicium and the date of his appointment to be the secretary a rationibus are subject to disput. (shrink)

This article describes new aspects of hysteresis dynamics which have been uncovered through computer experiments. There are several motivations to be interested in fast-slow dynamics. For instance, many physiological or biological systems display different time scales. The bursting oscillations which can be observed in neurons, β-cells of the pancreas and population dynamics are essentially studied via bifurcation theory and analysis of fast-slow systems (Keener and Sneyd, 1998; Rinzel, 1987). Hysteresis is a possible mechanism to generate bursting oscillations. A first part (...) of this article presents the computer techniques (the dotted-phase portrait, the bifurcation of the fast dynamics and the wave form) we have used to represent several patterns specific to hysteresis dynamics. This framework yields a natural generalization to the notion of bursting oscillations where, for instance, the active phase is chaotic and alternates with a quiescent phase. In a second part of the article, we emphasize the evolution to chaos which is often associated with bursting oscillations on the specific example of the Hindmarsh–Rose system. This evolution to chaos has already been studied with classical tools of dynamical systems but we give here numerical evidence on hysteresis dynamics and on some aspects of the wave form. The analytical proofs will be given elsewhere. (shrink)

We say that a ring admits elimination of quantifiers, if in the language of rings, {0, 1, +, ·}, the complete theory of R admits elimination of quantifiers. Theorem 1. Let D be a division ring. Then D admits elimination of quantifiers if and only if D is an algebraically closed or finite field. A ring is prime if it satisfies the sentence: ∀ x ∀ y ∃ z (x = 0 ∨ y = 0 ∨ xzy ≠ 0). Theorem (...) 2. If R is a prime ring with an infinite center and R admits elimination of quantifiers, then R is an algebraically closed field. Let A be the class of finite fields. Let B be the class of 2 × 2 matrix rings over a field with a prime number of elements. Let C be the class of rings of the form $GF(p^n) \bigoplus GF(p^k)$ such that either n = k or g.c.d. (n, k) = 1. Let D be the set of ordered pairs (f, Q) where Q is a finite set of primes and f: Q → A ∪ B ∪ C such that the characteristic of the ring f(q) is q. Finally, let E be the class of rings of the form $\bigoplus_{q \in Q}f(q)$ for some (f, Q) in D. Theorem 3. Let R be a finite ring without nonzero trivial ideals. Then R admits elimination of quantifiers if and only if R belongs to E. Theorem 4. Let R be a ring with the descending chain condition of left ideals and without nonzero trivial ideals. Then R admits elimination of quantifiers if and only if R is an algebraically closed field or R belongs to E. In contrast to Theorems 2 and 4, we have Theorem 5. If R is an atomless p-ring, then R is finite, commutative, has no nonzero trivial ideals and admits elimination of quantifiers, but is not prime and does not have the descending chain condition. We also generalize Theorems 1, 2 and 4 to alternative rings. (shrink)

Introduction / Alessandra Tanesini and Michael P. Lynch -- Reassessing different conceptions of argumentation / Catarina Dutilh Novaes -- Martial metaphors and argumentative virtues and vices / Ian James Kidd -- Arrogance and deep disagreement / Andrew Aberdein -- Closed-mindedness and arrogance / Heather Battaly -- Intellectual trust and the marketplace of ideas / Allan Hazlett -- Is searching the Internet making us intellectually arrogant? / J. Adam Carter and Emma C. Gordon -- Intellectual humility and the curse of knowledge (...) / Michael Hannon -- Bullshit and dogmatism : a discourse analytical perspective / Chris Heffer -- Polarization and the problem of spreading arrogance / Michael P. Lynch -- Arrogance, polarization and arguing to win / Alessandra Tanesini -- Partisanship, humility, and epistemic polarization / Thomas Nadelhoffer, Rose Graves, Gus Skorburg, Mark Leary, and Walter Sinnott-Armstrong -- Science denial, polarization, and arrogance / Lee McIntyre -- The polarization toolkit / Quassim Cassam -- Epistemic rights in a polarized world : the right to know and the abortion / Debate Lani Watson. (shrink)

BackgroundConventionally, transcranial direct current stimulation (tDCS) aims to focalize the current reaching the target region-of-interest (ROI). The focality can be quantified by the dose-target-determination-index (DTDI). Despite having a uniform tDCS setup, some individuals receive focal stimulation (high DTDI) while others show reduced focality (“non-focal”). The volume of cerebrospinal fluid (CSF), gray matter (GM), and white matter (WM) underlying each ROI govern the tDCS current distribution inside the brain, thereby regulating focality.AimTo determine the regional volume parameters that differentiate the focal and (...) non-focal groups.MethodsT1-weighted images of the brain from 300 age-sex matched adults were divided into three equal groups- (a) Young (20 ≤ × < 40 years), (b) Middle (40 ≤ × < 60 years), and (c) Older (60 ≤ × < 80 years). For each group, inter and intra-hemispheric montages with electrodes at (1) F3 and right supraorbital region (F3-RSO), and (2) CP5 and Cz (CP5-Cz) were simulated, targeting the left- Dorsolateral Prefrontal Cortex (DLPFC) and -Inferior Parietal Lobule (IPL), respectively. Both montages were simulated for two current doses (1 and 2 mA). For each individual head simulated for a tDCS configuration (montage and dose), the current density at each region-of-interest (ROI) and their DTDI were calculated. The individuals were categorized into two groups- (1) Focal (DTDI ≥ 0.75), and (2) Non-focal (DTDI < 0.75). The regional volume of CSF, GM, and WM of all the ROIs was determined. For each tDCS configuration and ROI, three 3-way analysis of variance was performed considering- (i) GM, (ii) WM, and (iii) CSF as the dependent variable (DV). The age group, sex, and focality group were the between-subject factors. For a given ROI, if any of the 3 DV’s showed a significant main effect or interaction involving the focality group, then that ROI was classified as a “focal ROI.”ResultsRegional CSF was the principal determinant of focality. For interhemispheric F3-RSO montage, interaction effect (p < 0.05) of age and focality was observed at Left Caudate Nucleus, with the focal group exhibiting higher CSF volume. The CSF volume of focal ROI correlated positively (r ∼ 0.16, p < 0.05) with the current density at the target ROI (DLPFC). For intrahemispheric CP5-Cz montage, a significant (p < 0.05) main effect was observed at the left pre- and post-central gyrus, with the focal group showing lower CSF volume. The CSF volume correlated negatively (r ∼ –0.16, p < 0.05) with current density at left IPL. The results were consistent for both current doses.ConclusionThe CSF channels the flow of tDCS current between electrodes with focal ROIs acting like reservoirs of current. The position of focal ROI in the channel determines the stimulation intensity at the target ROI. For focal stimulation in interhemispheric F3-RSO, the proximity of focal ROI reserves the current density at the target ROI (DLPFC). In contrast, for intrahemispheric montage (CP5-Cz), the far-end location of focal ROI reduces the current density at the target (IPL). (shrink)

Among the results of this paper are the following: 1. Every Boolean (ultra) power is the union of an updirected elementary family of direct ultrapowers. 2. Under certain conditions, a finitely iterated Boolean ultrapower is isomorphic to a single Boolean ultrapower. 3. A ω-bounded filtral power is an elementary substructure of a filtral power. 4. Let K be an elementary class closed under updirected unions (e.g., if K is an amalgamation class); then K is closed under finite products if and (...) only if K is closed under reduced products if and only if K is a Horn class. (shrink)

Among the results of this paper are the following: 1. Every Boolean power is the union of an updirected elementary family of direct ultrapowers. 2. Under certain conditions, a finitely iterated Boolean ultrapower is isomorphic to a single Boolean ultrapower. 3. A $\omega$-bounded filtral power is an elementary substructure of a filtral power. 4. Let $\mathscr{K}$ be an elementary class closed under updirected unions ; then $\mathscr{K}$ is closed under finite products if and only if $\mathscr{K}$ is closed under reduced (...) products if and only if $\mathscr{K}$ is a Horn class. (shrink)

The notion that our society, its education system and its intellectual life, is characterised by a split between two cultures – the arts or humanities on one hand and the sciences on the other – has a long history. But it was C. P. Snow's Rede lecture of 1959 that brought it to prominence and began a public debate that is still raging in the media today. This fiftieth anniversary printing of The Two Cultures and its successor piece, A Second (...) Look features an introduction by Stefan Collini, charting the history and context of the debate, its implications and its afterlife. The importance of science and technology in policy run largely by non-scientists, the future for education and research, and the problem of fragmentation threatening hopes for a common culture are just some of the subjects discussed. (shrink)

OBJECTIVES: To compare 2005 and 1995 ethics guidelines from journal editors to authors regarding requirements for institutional review board (IRB) approval and conflict-of-interest (COI) disclosure. DESIGN: A descriptive study of the ethics guidelines published in 103 English-language biomedical journals listed in the Abridged Index Medicus in 1995 and 2005. Each journal was reviewed by the principal author and one of four independent reviewers. RESULTS: During the period, the proportion of journals requiring IRB approval increased from 42% (95% CI 32.2% to (...) 51.2%, p<0.001) to 76% (95% CI 66.4% to 83.1%, p<0.001). In 2005, an additional 9% referred to the Declaration of Helsinki or the International Committee of Medical Journal Editors' Uniform requirements for ethical guidelines; 15% (95% CI 8.5% to 22.5%, p<0.01) provided ambiguous or no requirements. The proportion of journals requiring COI disclosure increased from 75% (95% CI 66.6% to 83.3%, p<0.05) to 94% (95% CI 89.4% to 98.6%, p<0.05); 41% had comprehensive requirements, while some addressed only funding source (6%), were vague (10%) or both (14%). Criteria for authorship rose from 40% (95% CI 30.5% to 49.5%, p<0.05) to 72% (95% CI 63.3% to 80.7%, p<0.05). Journals with higher impact factors were more likely to require IRB approval (p<0.01). Journals in anaesthesia and radiology all required IRB approval; requirements in other disciplines varied. CONCLUSIONS: Instructions to authors regarding ethical standards have improved. Some remain incomplete, especially regarding the scope of disclosure of COI. The ethical guidelines presented to authors need further clarification and standardisation. (shrink)

The notion that our society, its education system and its intellectual life, is characterised by a split between two cultures – the arts or humanities on one hand, and the sciences on the other – has a long history. But it was C. P. Snow's Rede lecture of 1959 that brought it to prominence and began a public debate that is still raging in the media today. This 50th anniversary printing of The Two Cultures and its successor piece, A Second (...) Look features an introduction by Stefan Collini, charting the history and context of the debate, its implications and its afterlife. The importance of science and technology in policy run largely by non-scientists, the future for education and research, and the problem of fragmentation threatening hopes for a common culture are just some of the subjects discussed. (shrink)

The view that phenomenally conscious robots are on the horizon often rests on a certain philosophical view about consciousness, one we call “nomological behaviorism.” The view entails that, as a matter of nomological necessity, if a robot had exactly the same patterns of dispositions to peripheral behavior as a phenomenally conscious being, then the robot would be phenomenally conscious; indeed it would have all and only the states of phenomenal consciousness that the phenomenally conscious being in question has. We experimentally (...) investigate whether the folk think that certain (hypothetical) robots made of silicon and steel would have the same conscious states as certain familiar biological beings with the same patterns of dispositions to peripheral behavior as the robots. Our findings provide evidence that the folk largely reject the view that silicon-based robots would have the sensations that they, the folk, attribute to the biological beings in question. (shrink)

Offering an original perspective on the central project of Descartes' Meditations, this book argues that Descartes' free will theodicy is crucial to his refutation of skepticism. A common thread runs through Descartes' radical First Meditation doubts, his Fourth Meditation discussion of error, and his pious reconciliation of providence and freedom: each involves a clash of perspectives-thinking of God seems to force conclusions diametrically opposed to those we reach when thinking only of ourselves. Descartes fears that a skeptic could exploit this (...) clash of perspectives to argue that Reason is not trustworthy because self-contradictory. To refute the skeptic and vindicate the consistency of Reason, it is not enough for Descartes to demonstrate that our Creator is perfect; he must also show that our errors cannot prove God's imperfection. To do this, Descartes invokes the idea that we err freely. However, prospects initially seem dim for this free will theodicy, because Descartes appears to lack any consistent or coherent understanding of human freedom. In an extremely in-depth analysis spanning four chapters, Ragland argues that despite initial appearances, Descartes consistently offered a coherent understanding of human freedom: for Descartes, freedom is most fundamentally the ability to do the right thing. Since we often do wrong, actual humans must therefore be able to do otherwise-our actions cannot be causally determined by God or our psychology. But freedom is in principle compatible with determinism: while leaving us free, God could have determined us to always do the good. Though this conception of freedom is both consistent and suitable to Descartes' purposes, when he attempts to reconcile it with divine providence, Descartes's strategy fails, running afoul of his infamous doctrine that God created the eternal truths. (shrink)

In an influential article, Anthony Kenny charged that (a) the view of freedom in Descartes’ “1645 letter to Mesland” is incoherent, and (b) that this incoherence was present in Descartes’ thought from the beginning. Against (b), I argue that such incoherence would rather support Gilson’s suspicions that the 1645 letter is dishonest. Against (a), I offer a close reading of the letter, showing that Kenny’s objection seems plausible only if we misconstrue a key ambiguity in the text. I close by (...) defending Descartes against some related worries of my own about the degrees of Cartesian freedom. I conclude that there is really no good reason to deny that Descartes’ view in the 1645 letter is both internally coherent and a genuine explication of the Meditations’ account of freedom. (shrink)

Introduction THOMAS C. HELLER AND DAVID E. WELLBERY A he essays that follow originated in a conference entitled "Reconstructing Individualism," held at ...

Dan Baras has recently argued for the claim that Theistic Mathematical Platonism fares no better than Mathematical Platonism with respect to explaining why our mathematical beliefs are correlated with mind-independent mathematical truths. In this paper I argue that, insofar as TMP provides a proximate or local explanation for this truth-tracking correlation whereas MP fails to offer any corresponding explanation, Baras’s claim that TMP fares no better than MP with respect to explaining this correlation is false.

In this interview, C. P. Goodman invites British Polanyi scholar Richard T. Allen to reflect on his interest in Polanyi’s philosophical ideas and share what he believes is valuable in his thought.

The principle of alternative possibilities (PAP) says that doing something freely implies being able to do otherwise. I show that Descartes consistently believed not only in PAP, but also in clear and distinct determinism (CDD), which claims that we sometimes cannot but judge true what we clearly perceive. Because Descartes thinks judgment is always a free act, PAP and CDD seem contradictory, but Descartes consistently resolved this apparent contradiction by distinguishing between two senses of 'could have done otherwise.' In one (...) sense alternative possibilities are necessary for freedom and in another they are not. I discuss three possible interpretations of the two senses. (shrink)