For T any completion of Peano Arithmetic and for n any positive integer, there is a model of T of size $\beth_n$ with no (n + 1)-length sequence of indiscernibles. Hence the Hanf number for omitting types over T, H(T), is at least $\beth_\omega$ . (Now, using an upper bound previously obtained by Julia Knight H (true arithmetic) is exactly $\beth_\omega$ ). If T ≠ true arithmetic, then $H(T) = \beth_{\omega1}$ . If $\delta \not\rightarrow (\rho)^{ , then any completion of (...) Peano Arithmetic has a model of size δ with no set of indiscernibles of size ρ. There are similar results for theories strongly resembling Peano Arithmetic, e.g., ZF + V = L. (shrink)

Dehumanization is routinely invoked in social science and law as the primary factor in explaining how propaganda encourages support for, or participation in, violence against targeted outgroups. Yet the primacy of dehumanization is increasingly challenged by the apparent influence of revenge on collective violence. This study examines critically how various propaganda influence audiences. Although previous research stresses the dangers of dehumanizing propaganda, a recently published study found that only revenge propaganda significantly lowered outgroup empathy. Given the importance of these findings (...) for law and the behavioral sciences, this research augments that recent study with two additional samples that were culturally distinct from the prior findings, showing again that only revenge propaganda was significant. To explore this effect further, we also conducted a facial electromyography (fEMG) among a small set of participants, finding that revenge triggered significantly stronger negative emotions against outgroups than dehumanization. (shrink)

We show that the double jump is definable in the computably enumerable sets. Our main result is as follows: let [Formula: see text] is the Turing degree of a [Formula: see text] set J ≥T0″}. Let [Formula: see text] such that [Formula: see text] is upward closed in [Formula: see text]. Then there is an ℒ property [Formula: see text] such that [Formula: see text] if and only if there is an A where A ≡T F and [Formula: see text]. (...) A corollary of this is that, for all n ≥ 2, the high n computably enumerable degrees are invariant in the computably enumerable sets. Our work resolves Martin's Invariance Conjecture. (shrink)

This article reviews Fernando Leal and Hubert Marraud’s How Philosopher’s Argue: An Adversarial Collaboration on the Russell-Copleston Debate (Springer 2022).

The purpose of this communication is to announce some recent results on the computably enumerable sets. There are two disjoint sets of results; the first involves invariant classes and the second involves automorphisms of the computably enumerable sets. What these results have in common is that the guts of the proofs of these theorems uses a new form of definable coding for the computably enumerable sets.We will work in the structure of the computably enumerable sets. The language is just inclusion, (...) ⊆. This structure is called ε.All sets will be computably enumerable non-computable sets and all degrees will be computably enumerable and non-computable, unless otherwise noted. Our notation and definitions are standard and follow Soare [1987]; however we will warm up with some definitions and notation issues so the reader need not consult Soare [1987]. Some historical remarks follow in Section 2.1 and throughout Section 3.We will also consider the quotient structure ε modulo the ideal of finite sets, ε*. ε* is a definable quotient structure of ε since “Χ is finite” is definable in ε; “Χ is finite” iff all subsets of Χ are computable. We use A* to denote the equivalent class of A under the ideal of finite sets. (shrink)

We show that if A and $\widehat{A}$ are automorphic via Φ then the structures $S_{R}(A)$ and $S_{R}(\widehat{A})$ are $\Delta_{3}^{0}-isomorphic$ via an isomorphism Ψ induced by Φ. Then we use this result to classify completely the orbits of hhsimple sets.

Newborn screening involves a complex logistical process, which depends on the close cooperation of many professionals, such as midwives, laboratory technicians, general practitioners and pediatricians. These professionals may encounter moral problems in the process, which have not been systematically studied before. This study fills this gap. We conducted interviews with 36 professionals involved in NBS in the Netherlands and made an inventory of the moral problems they encounter, as well as of the ways in which they tend to respond to (...) them. The moral problems professionals encounter stem from interpersonal conflicts and intrapersonal conflicts. Given the complexity of the work of NBS professionals, the study suggests that the moral problems that occur on the work floor cannot easily be solved by means of offering better or more stringent policy guidelines. Rather, it should be appreciated that professionals contribute significantly to shaping the morality of NBS with the help of their daily choices, and they should be supported in carrying out this task—for example with the help of a moral training or regular multidisciplinary moral deliberation, facilitated by an ethicist. (shrink)

The goal of this paper is to announce there is a single orbit of the c.e. sets with inclusion, ε, such that the question of membership in this orbit is ${\Sigma _1^1 }$ -complete. This result and proof have a number of nice corollaries: the Scott rank of ε is $\omega _1^{{\rm{CK}}}$ + 1; not all orbits are elementarily definable; there is no arithmetic description of all orbits of ε; for all finite α ≥ 9, there is a properly $\Delta (...) _\alpha ^0 $ orbit (from the proof). (shrink)

Contemporary policymakers, as their predecessors, continue to view nomadic people as a weak minority, and their way of life and raising livestock as a backward and inefficient paradigm. Wherever nomads are not the dominant group, the trend to settle them continues even today as in the past. This book describes the changes forced upon formerly nomadic groups and how they still attempt to maintain their traditional, social, and cultural practices in their new settings. The book deals with the several modes (...) of livelihood of these communities, including entrepreneurship, and demonstrates the impact of investment-oriented urbanization policies leading to eviction from ancestral lands, and hurdles for nomadic mobility, ultimately threatening their survival. The book illustrates how some groups like the Borana and the Maasai practice livelihood diversity and raise productive livestock, and how other groups migrate to urban centers in search of employment and remit money to family members left in the rural areas. The book aims to raise awareness among the research community, especially those who work on regional and demographic labor policies. It helps in understanding why society needs to help build business and livelihood strategies without harming the values of nomadic groups. (shrink)