Spontaneous discrimination of small quantities: shoaling preferences in angelfish (<Emphasis Type="Italic">Pterophyllum scalare</Emphasis>)

The ability to quantify, i.e. to estimate quantity, may provide evolutionary advantages in some contexts and has been demonstrated in a variety of animal species. In a prior study, we showed that angelfish (Pterophyllum scalare) were able to discriminate between groups (shoals) in which a large number of conspecifics swam preferring to join the larger of the two. Our results implied that angelfish can compare relative shoal sizes likely on the basis of some quantitative attributes of the shoal. Here, also using a binary preference test, we examined whether angelfish are able to discriminate between shoals of small numbers of conspecifics, and if so whether their performance reveals a comparable underlying mechanism to that proposed for discrimination of small quantities in human and non-human animals, namely the possible precursor of the ability to count. Our results demonstrate that fish reliably chose 4 versus 1, 3 versus 1, 2 versus 1 and 3 versus 2 individuals, but were at chance performance level when having to choose between 4 versus 3, 5 versus 4 and 6 versus 5. Findings also reveal that the density of the fish in the stimulus shoals did not significantly affect the performance of experimental angelfish. These results are compatible with the hypothesis of the existence of an object-file mechanism to discriminate small quantities in vertebrates and provide evidence for spontaneous discrimination of up to three elements in angelfish, a similar limit to that found in human and non-human animals. The findings add to the growing body of data, suggesting that the mechanisms underlying discrimination between different quantities of items may be shared across different taxa and have an evolutionary ancient origin.     

Combinations of <Emphasis Type="Italic">Stit</Emphasis> with <Emphasis Type="Italic">Ought</Emphasis> and <Emphasis Type="Italic">Know</Emphasis>

This paper presents a short survey of recent developments in stit theories, with an emphasis on combinations of stit and deontic logic, and those of stit and epistemic logic.     

<Emphasis Type="Italic">Ziran</Emphasis> and <Emphasis Type="Italic">Wuwei</Emphasis> in the <Emphasis Type="Italic">Daodejing</Emphasis>: An Ethical Assessment

In Daoist philosophy, the self is understood as an individual interdependent with others, and situated within a broader environment. Within this framework, the concept ziran is frequently understood in terms of naturalness or nature while wuwei is explained in terms of non-oppressive government. In many existing accounts, little is done to connect these two key Daoist concepts. Here, I suggest that wuwei and ziran are correlated, ethical, concepts. Together, they provide a unifying ethical framework for understanding the philosophy of the Daodejing. I explore the meaning of ziran as self-so-ness or, in human terms, as pertaining to an individual’s spontaneity. The appropriate response to the spontaneity of individuals is to avoid, insofar as possible, imposing or using restrictive norms and methods, that is, wuwei. According to this view, ziran and wuwei offer an account of ethics that attends to core notions of interdependent selfhood, including mutuality, relationality, interdependence, symbiosis, and responsiveness.     

<Emphasis Type="Italic">Ceteris</Emphasis>-<Emphasis Type="Italic">Paribus</Emphasis> Qualifiers

Antecedent-strengthening, a trivially valid inference of classical logic of the form: P → Q ? (P & R) → Q, has a counterpart in everyday reasoning that often fails. A plausible solution to the problem involves assuming an implicit ceteris paribus (CP) qualifier that can be explicated as an additional conjunct in the antecedent of the premise. The qualifier can be explicated as ‘everything else relevant remains unchanged’ or alternatively as ‘nothing interferes’. The qualifier appears most prominently in the context of the discussion of laws in the sciences, where these laws are often expressed with a CP qualifier. From an analysis of the qualifier’s role in the problem of antecedent-strengthening, we can learn more about CP qualifiers in general and in their application to the laws used in the sciences.     

Deontological evidentialism and <Emphasis Type="Italic">ought</Emphasis> implies <Emphasis Type="Italic">can</Emphasis>

Deontological evidentialism is the claim that S ought to form or maintain S’s beliefs in accordance with S’s evidence. A promising argument for this view turns on the premise that consideration c is a normative reason for S to form or maintain a belief that p only if c is evidence that p is true. In this paper, I discuss the surprising relation between a recently influential argument for this key premise and the principle that ought implies can. I argue that anyone who antecedently accepts or rejects this principle already has a reason to resist either this argument’s premises or its role in support of deontological evidentialism.     

Revalidation of the <Emphasis Type="Italic">Sat</Emphasis>-<Emphasis Type="Italic">Chit</Emphasis>-<Emphasis Type="Italic">Ananda</Emphasis> Scale

Sat-Chit-Ananda is an indigenous construct that refers to absolute bliss and consciousness. The present study aimed to strengthen the psychometric properties of the newly developed Sat-Chit-Ananda scale (Singh et al. in Int J Vedic Found Manag 1(2):54–74, 2014). A total of 398 students aged 17–36 years (mean age = 21.33 years, SD = 2.2, 70% males) participated in this study. An exploratory as well as confirmatory factor analysis was computed for the 17-item scale. Its’ concurrent validity was established by assessing its correlation with other well-being measures, namely Flourishing (Diener et al. in Soc Indic Res 97:143–156 2010) and Scale of Positive and Negative Experience (Diener et al. 2010). Satisfactory results were obtained from both exploratory and confirmatory factor analyses. Sat-Chit-Ananda and its factors were found to be significantly positively correlated with Flourishing and Positive Experiences and were negatively correlated with Negative Experiences. Thus, the validity of the Sat-Chit-Ananda (Singh et al. 2014) scale stands further substantiated—offering this scale as a promising new assessment tool.     

Robust representations of individual faces in chimpanzees (<Emphasis Type="Italic">Pan troglodytes</Emphasis>) but not monkeys (<Emphasis Type="Italic">Macaca mulatta</Emphasis>)

Being able to recognize the faces of our friends and family members no matter where we see them represents a substantial challenge for the visual system because the retinal image of a face can be degraded by both changes in the person (age, expression, pose, hairstyle, etc.) and changes in the viewing conditions (direction and degree of illumination). Yet most of us are able to recognize familiar people effortlessly. A popular theory for how face recognition is achieved has argued that the brain stabilizes facial appearance by building average representations that enhance diagnostic features that reliably vary between people while diluting features that vary between instances of the same person. This explains why people find it easier to recognize average images of people, created by averaging multiple images of the same person together, than single instances (i.e. photographs). Although this theory is gathering momentum in the psychological and computer sciences, there is no evidence of whether this mechanism represents a unique specialization for individual recognition in humans. Here we tested two species, chimpanzees (Pan troglodytes) and rhesus monkeys (Macaca mulatta), to determine whether average images of different familiar individuals were easier to discriminate than photographs of familiar individuals. Using a two-alternative forced-choice, match-to-sample procedure, we report a behaviour response profile that suggests chimpanzees encode the faces of conspecifics differently than rhesus monkeys and in a manner similar to humans.     

The codification of intersubjectivity in the diachronic change <Emphasis Type="Italic">AD locative</Emphasis> &gt; <Emphasis Type="Italic">A</Emphasis>(<Emphasis Type="Italic">D</Emphasis>) <Emphasis Type="Italic">indirect object</Emphasis> in Spanish

The principal aim of this paper is to analyze the relationship between intersubjectivity and grammar. We argue that intersubjectivity represents, on the one hand, a prerequisite for the development of language as a symbolic system, and therefore also for the development of grammar. Furthermore, we attempt to show that language, and especially grammar, codify intersubjectivity. That is to say, grammatical constructions represent the intersubjective interactions that situated agents maintain in different pragmatic contects. We call this phenomenon the meta-representational capacity of language. Our main object of analysis is the development of the ditransitive construction (give something to someone - dar algo a alguien) in the Spanish language. The evolution of this construction makes it clear that there is an important correlation between the degree of complexity of the codified intersubjective interaction and grammatically obligatory nature and the prominence of the grammatical construction that codifies it: the greater the complexity, the greater its obligatoriness, and vice versa.     

When quantity trumps number: discrimination experiments in cotton-top tamarins (<Emphasis Type="Italic">Saguinus oedipus</Emphasis>) and common marmosets (<Emphasis Type="Italic">Callithrix jacchus</Emphasis>)

The capacity for non-linguistic, numerical discrimination has been well characterized in non-human animals, with recent studies providing careful controls for non-numerical confounds such as continuous extent, density, and quantity. More poorly understood are the conditions under which animals use numerical versus non-numerical quantification, and the nature of the relation between these two systems. Here we test whether cotton-top tamarins and common marmosets can discriminate between two quantities on the basis of the amount of food rather than on number. In three experiments, we show that when choosing between arrays containing different numbers and sizes of food objects, both species based their decisions on the amount of food with only minor influences of numerical information. Further, we find that subjects successfully discriminated between two quantities differing by a 2:3 or greater ratio, which is consistent with the ratio limits found for numerical discrimination with this species. These studies demonstrate that non-human primates possess mechanisms that enable quantification of total amount, in addition to the numerical representations demonstrated in previous studies, with both types of quantification subject to similar processing limits.     

That <Emphasis Type="Italic">F</Emphasis>

Jeffrey King’s principal objection to the direct-reference theory of demonstratives is analyzed and criticized. King has responded with a modified version of his original argument aimed at establishing the weaker conclusion that the direct-reference theory of demonstratives is either incomplete or incorrect. It is argued that this fallback argument also fails.

Color and intensity discrimination in <Emphasis Type="Italic">Xenopus laevis</Emphasis> tadpoles

Investigations into the physiology of Xenopus laevis have the potential to greatly accelerate biomedical research, especially concerning neural plasticity and sensory systems, but are limited by the lack of available information on behavioral learning in this species. Here, we attempt to lay the foundations for a behavioral assay in Xenopus that can be used in conjunction with biological manipulations. We tested cohorts of Xenopus tadpoles across four light-mediated active-avoidance experiments, using either wavelength or intensity as the salient discriminative cue. In the wavelength task, we determine a baseline learning rate and characterize retention of learning, identifying active extinction effects as far more potent than the passage of time in the loss of behavior. In the intensity task, we examine the effects of varying differences between the discriminative stimuli on acquisition and extinction and identify a critical range of intensity differences where learning changes. The results of our experiments demonstrate that Xenopus is a tractable model organism for cognitive research and can learn a variety of associative tasks in the laboratory settings. These data reveal new aspects of the Xenopus larval visual processing system and facilitate future research between cognitive methods and biological/chemical manipulations to study mechanisms of brain structure and function.     

A Definition Framework for the Terms <Emphasis Type="Italic">Nanomaterial</Emphasis> and <Emphasis Type="Italic">Nanoparticle</Emphasis>

Scientific writings and policy documents define the terms nanomaterial and nanoparticle in various ways. This variation is considered problematic because the absence of a shared definition is understood as potentially hindering nanomaterial knowledge production and regulation. Another view is that the existence of a shared definition may itself cause problems, as rigid definitions arguably exclude important aspects of the studied phenomena. The aim of this paper is to inform this state of disagreement by providing analytical concepts for a systematic understanding of how, and even whether, nanomaterial and nanoparticle could and should be defined. To do this, we review definitions of nanomaterial and nanoparticle presented in research articles and policy documents. Definitions were identified by first conducting a Scopus search and then tracing cited definitions back to their sources. In total, 36 definitions were identified. Theories of definition from philosophy and linguistics provide analytical guidance for structuring and categorizing the identified definitions, and the main analytical dimensions of the definitions are then identified and discussed. Finally, we propose a framework for understanding the process of defining nanomaterial and nanoparticle. This framework considers both the generality needed for a shared understanding (by suggesting proto-definitions of nanomaterial and nanoparticle) and the level of precision required for different purposes (by allowing for various explications of the proto-definitions).     

Three-Valued Temporal Logic <Emphasis Type="Italic">Q</Emphasis><Subscript><Emphasis Type="Italic">t</Emphasis></Subscript> and Future Contingents

Prior’s three-valued modal logic Q was developed as a philosophically interesting modal logic. Thus, we should be able to modify Q as a temporal logic. Although a temporal version of Q was suggested by Prior, the subject has not been fully explored in the literature. In this paper, we develop a three-valued temporal logic Q _t and give its axiomatization and semantics. We also argue that Q _t provides a smooth solution to the problem of future contingents. Presented by Daniele Mundici     

The Problem of <Emphasis Type="Italic">Bildung</Emphasis> and the Basic Structure of <Emphasis Type="Italic">Bildungstheorie</Emphasis>

In this article, an attempt is made to introduce a systematization of the loosely connected group of authors called Bildungstheorie. This ought to not only be of significance for German-speaking educational science, for the concept of Bildung is also increasingly used internationally for the formulation and development of pedagogical issues. It is proposed that the concept of complexity could be suitable for bringing attention to common presuppositions in the theoretical dealing with the problem of Bildung. The thesis is that Bildung in theories of Bildung is described from various perspectives as complex, meaning it is an open and uncertain interplay of components irreducibly associated with planning and governance problems. As this thesis is corroborated by means of selected positions within Bildungstheorie, evidence is provided that complexity in educational science—differently than it may seem at first glance—is not for the first time today a theme of importance. Rather, it is demonstrated that a nascent discipline-specific complexity research can be linked to already existing traditions.     

Rescue of newborn ants by older <Emphasis Type="Italic">Cataglyphis</Emphasis><Emphasis Type="Italic">cursor</Emphasis> adult workers

Cataglyphis cursor worker ants are capable of highly sophisticated rescue behaviour in which individuals are able to identify what has trapped a nestmate and to direct their behaviour towards that obstacle. Nonetheless, rescue behaviour is constrained by workers’ subcaste: whereas foragers, the oldest workers, are able both to give and to receive the most help, the youngest workers, inactives, neither give nor receive any help whatsoever; nurses give and receive intermediate levels of aid, reflecting their intermediate age. Such differences in rescue behaviour across subcastes suggest that age and experience play a critical role. In this species, as in many others in which a sensitive period for nestmate recognition exists, newly enclosed ants, called callows, are adopted by ants belonging not only to different colonies but also to different species; foreign callows receive nearly the same special care provided to resident newborns. Because callows are younger than inactives, which are incapable of soliciting rescue, we wondered whether entrapped callows would receive such aid. In the present study, we artificially ensnared individual callows from their own colony (homocolonial), from a different colony (heterocolonial), and from a different species (heterospecific), and tested each one with groups of five potential C. cursor rescuers, either all foragers or all nurses. Our results show that all three types of callows are able to elicit rescue behaviour from both foragers and nurses. Nonetheless, nurse rescuers are better able to discriminate between the three types of callow victims than are foragers.