The primitive streak establishes the antero‐posterior body axis in all amniote species. It is thought to be the conduit through which mesoderm and endoderm progenitors ingress and migrate to their ultimate destinations. Despite its importance, the streak remains poorly defined and one of the most enigmatic structures of the animal kingdom. In particular, the posterior end of the primitive streak has not been satisfactorily identified in any species. Unexpectedly, and contrary to prevailing notions, recent evidence suggests that (...) the murine posterior primitive streak extends beyond the embryo proper. In its extraembryonic site, the streak creates a node‐like cell reservoir from which the allantois, a universal caudal appendage of all amniotes and the future umbilical cord of placental mammals, emerges. This new insight into the fetal/umbilical relationship may explain the etiology of a large number of umbilical‐associated birth defects, many of which are correlated with abnormalities of the embryonic midline. (shrink)

In vertebrates the antero‐posterior organization of the embryonic body axis is thought to result from the activity of two separate centers, the head organizer and the trunk organizer, as operationally defined by Spemann in the 1920s. Current molecular studies have supported the existence of a trunk organizer activity while the presence of a distinct head inducing center has remained elusive. Mainly based on analyses of headless mutants in mice, it has been proposed that the anterior axial mesoderm plays (...) a determining role in head induction. Recent gain‐ and loss‐of‐function studies in various organisms, however, provide compelling evidence that a largely ignored region, the anterior primitive endoderm, specifies rostral identity. In this review we discuss the emerging concept that the anterior primitive endoderm, rather than the prechordal plate mesoderm, induces head development in the vertebrate embryo. (shrink)

Somites are transient structures which represent the most overt segmental feature of the vertebrate embryo. The strict temporal regulation of somitogenesis is of critical developmental importance since many segmental structures adopt a periodicity based on that of the somites. Until recently, the mechanisms underlying the periodicity of somitogenesis were largely unknown. Based on the oscillations of c-hairy1 and lunatic fringe RNA, we now have evidence for an intrinsic segmentation clock in presomitic cells. Translation of this temporal periodicity into a spatial (...) periodicity, through somite formation, requires Notch signaling. While the Hox genes are certainly involved, it remains unknown how the metameric vertebrate axis becomes regionalized along the antero–posterior (AP) dimension into the occipital, cervical, thoracic, lumbar, and sacral domains. We discuss the implications of cell division as a clock mechanism underlying the regionalization of somites and their derivatives along the AP axis. Possible links between the segmentation clock and axial regionalization are also discussed. (shrink)

Embryonic development results in animals whose body plans exhibit a variety of symmetry types. While significant progress has been made in understanding the molecular events underlying the early specification of the antero‐posterior and dorso‐ventral axes, little information has been available regarding the basis for left‐right (LR) differences in animal morphogenesis. Recently however, important advances have been made in uncovering the molecular mechanisms responsible for LR patterning. A number of genes (including well‐known signaling molecules such as Sonic hedgehog and (...) activin) are asymmetrically expressed in early chick embryos, well before the appearance of morphological asymmetries. One of these, nodal, is asymmetrically expressed in frogs and mice as well, and its expression is altered in mouse mutants exhibiting defects in laterality. In the chick, these genes regulate each other in a sequential cascade, which independently determines the situs of the heart and other organs. (shrink)

The evolutionarily conserved genomic organization of the Hox genes has been a puzzle ever since it was discovered that their order along the chromosome is similar to the order of their functional domains along the antero‐posterior axis. Why has this colinearity been maintained throughout evolution? A close look at regulatory sequences from the mouse Hox clusters(1,2) suggests that enhancer sharing between adjacent Hox genes may be one reason. Moreover, characterizing the activity of one of these mouse enhancers in (...) Drosophila(2) illustrates that despite many similarities, not all Hox clusters are built in the same way. (shrink)

In the minds of many, Hox gene null mutant phenotypes have confirmed the direct role that these genes play in specifying the pattern of vertebrate embryos. The genes are envisaged as defining discrete spatial domains and, subsequently, conferring specific segmental identities on cells undergoing differentiation along the antero‐posterior axis. However, several aspects of the observed mutant phenotypes are inconsistent with this view. These include: the appearance of other, unexpected transformations along the dorsal axis; the occurrence of mirror‐image duplications; (...) and the development of anomalies outside the established domains of normal Hox gene expression. In this paper, Hox gene disruptions are shown to elicit regeneration‐like responses in tissues confronted with discontinuities in axial identity. The polarities and orientations of transformed segments which emerge as a consequence of this response obey the rules of distal transformation and intercalary regeneration. In addition, the incidence of periodic anomalies suggests that the initial steps of Hox‐mediated patterning occurs in Hensen's node. As gastrulation proceeds, mesoderm cell cycle kinetics impose constraints upon subsequent cellular differentiation. This results in the delayed manifestation of transformations along the antero‐posterior axis. Finally, a paradigm is sketched in which temporal, rather than spatial axial determinants direct differentiation. Specific, testable predictions are made about the role of Hox genes in the establishment of segmental identity. (shrink)

Motor Imagery reproduces cognitive operations associated with the actual motor preparation and execution. Postural recordings during MI reflect somatic motor commands targeting peripheral effectors involved in balance control. However, how these relate to the actual motor expertise and may vary along with the MI modality remains debated. In the present experiment, two groups of expert and non-expert gymnasts underwent stabilometric assessments while performing physically and mentally a balance skill. We implemented psychometric measures of MI ability, while stabilometric variables were calculated (...) from the center of pressure oscillations. Psychometric evaluations revealed greater MI ability in experts, specifically for the visual modality. Experts exhibited reduced surface COP oscillations in the antero-posterior axis compared to non-experts during the balance skill. Experts further exhibited reduced length of COP displacement in the antero-posterior axis and as a function of the displacement area during visual and kinesthetic MI compared to the control condition. Predictive relationships were found between the stabilometric correlates of visual MI and physical practice of the balance skill, as well as between the stabilometric correlates of kinesthetic MI and the training experience in experts. Present results provide original stabilometric insights into the relationships between MI and expertise level. While data support the incomplete inhibition of postural commands during MI, whether postural responses during MI of various modalities mirror the level of motor expertise remains unclear. (shrink)

Somites are transient structures which represent the most overt segmental feature of the vertebrate embryo. The strict temporal regulation of somitogenesis is of critical developmental importance since many segmental structures adopt a periodicity based on that of the somites. Until recently, the mechanisms underlying the periodicity of somitogenesis were largely unknown. Based on the oscillations of c-hairy1 and lunatic fringe RNA, we now have evidence for an intrinsic segmentation clock in presomitic cells. Translation of this temporal periodicity into a spatial (...) periodicity, through somite formation, requires Notch signaling. While the Hox genes are certainly involved, it remains unknown how the metameric vertebrate axis becomes regionalized along the antero–posterior (AP) dimension into the occipital, cervical, thoracic, lumbar, and sacral domains. We discuss the implications of cell division as a clock mechanism underlying the regionalization of somites and their derivatives along the AP axis. Possible links between the segmentation clock and axial regionalization are also discussed. BioEssays 22:72–83, 2000. ©2000 John Wiley & Sons, Inc. (shrink)

The aging process involves changes in immune regulation, i.e. adaptive immunity declines whereas innate immunity becomes activated. NF‐κB signaling is the master regulator of the both immune systems. Two recent articles highlight the role of the NF‐κB system in aging and immune responses. Adler et al1 showed that the NF‐κB binding domain is the genetic regulatory motif which is most strongly associated with the aging process. Kwon et al2 studying HIV‐1 infection and subsequent immune deficiency process demonstrated that HIV‐1 Tat (...) protein binds to SIRT1 protein, a well‐known longevity factor, and inhibits the SIRT1‐mediated deacetylation of the p65 component of the NF‐κB complex. As a consequence, the transactivation efficiency of the NF‐κB factor was greatly potentiated, leading to the activation of immune system and later to the decline of adaptive immunity. These observations support the scenario where immune responses and aging process can be enforced by the potentiation of NF‐κB transactivation efficiency. Longevity factors, such as SIRT1 and its activators, might regulate the efficiency of the NF‐κB signaling, the major outcome of which is inflamm‐aging via proinflammatory responses. BioEssays 30:939–942, 2008. © 2008 Wiley Periodicals, Inc. (shrink)

The foundations of AI design discourse are worth analyzing. Here, attention is paid to the nature of theory languages used in designing new AI technologies because the limits of these languages can clarify some fundamental questions in the development of AI. We discuss three types of theory language used in designing AI products: formal, computational, and natural. Formal languages, such as mathematics, logic, and programming languages, have fixed meanings and no actual-world semantics. They are context- and practically content-free. Computational languages (...) use terms referring to the actual world, i.e., to entities, events, and thoughts. Thus, computational languages have actual-world references and semantics. They are thus no longer context- or content-free. However, computational languages always have fixed meanings and, for this reason, limited domains of reference. Finally, unlike formal and computational languages, natural languages are creative, dynamic, and productive. Consequently, they can refer to an unlimited number of objects and their attributes in an unlimited number of domains. The differences between the three theory languages enable us to reflect on the traditional problems of strong and weak AI. (shrink)

Para San Juan de Ávila la salvación de las almas es el principal negocio de Dios que estará unido, dada su situación histórica, a la reforma de la Iglesia y de los pastores. La Iglesia y el sacramento del orden, tienen un origen y una realización concomitante, obran simultáneamente la salvación, ninguno de ellos es consecuencia del otro sino que ambos son en Cristo. El objetivo de este artículo es presentar la identidad eclesial del sacramento del orden desde la doctrina (...) de San Juan de Ávila. Las consecuencias de esta reflexión sobre la identidad eclesial del sacerdocio nos llevará a comprender la profundidad de la doctrina avilista y saber enriquecer la actual reflexión teológica. (shrink)

It is commonplace that the modern world is more international than at any point in human history. Yet the sheer profusion of terms for describing political orders above the nation-state-including "international," "global," "transnational," and "cosmopolitan," among others-is but one indication of how conceptually complex this topic actually is. Taking a wide view of international projects in Europe since the eighteenth century, Nationalism and Internationalism Intertwined explores discourses and practices to challenge nation-centered histories and trace the entanglements that arise from international (...) cooperation. In this volume, a multidisciplinary group of scholars in history, political science, philosophy, computer science, and other fields ask how internationalism and adjacent concepts have been experienced, understood, constructed, debated, and redefined across different European political cultures. (shrink)

Purpose – The purpose of this paper is to analyse the current status of ownership of patient information from a Lockean perspective and then present Datenherrschaft as a new model for patient ownership of patient information. Design/methodology/approach – This paper is theoretical in approach. It is based on arguments derived from Locke’s Two Treatises of Government. Legal examples of the current situation are derived from Finnish, UK and Swedish legislation. Findings – Current legislation concerning patient information is not clearly formulated (...) and so recognising a new right on the part of the patient, Datenherrschaft, would be an ethically justifiable way of remedying the issue. Research limitations/implications – The legal analysis was limited to Finland, the UK and Sweden, and so other legislation should be looked at in future research. Datenherrschaft is used as an example of an ethically justified way of regulating patient information ownership and should be analysed further. Originality/value – Patient information ownership is an issue that is not unambiguously solved in many countries, nor has it, in our view, been ethically justified. The potential solution presented in this paper is clear and has strong ethical justifications. (shrink)

In times of crisis, one of the areas heavily affected has been food, as a direct consequence of the damage caused to family farming and therefore to Food and Nutrition Security (SAN). Climate change, in turn, causes widespread crises, which, due to their impact on humanity, and above all, on SAN, provide complex humanitarian crises, worsening hunger. The military conflict imposes difficulties in access to food and production. This study aimed to critically describe the panorama of climate change and armed (...) conflicts in Africa, relating them to the pandemic of COVID-19 as a factor of aggravating the situation of food insecurity in African countries. A literature review study was carried out in various databases, journals and portals for this purpose, with emphasis on Google Scholar, CAPES and governmental portals. The results point to climate change, as being multicausal, and constitute a risk factor for agriculture and SAN, in African countries, characterized by the destruction of crops and the reduction of food availability. Armed conflicts makes difficult to produce and distribute food, especially for people who’s affected. (shrink)

During the past few years significant progress has been made in our understanding of the structure and function of the proteins involved in eukaryotic DNA replication. Data from several laboratories suggest that, in contrast to prokaryotic DNA replication, two distinct DNA polymerases are required for eukaryotic DNA replication, i.e. DNA polymerase delta for the synthesis of the leading strand and DNA polymerase alpha for the lagging strand. Several accessory proteins analogous to prokaryotic replication factors have been identified and some of (...) these are specific for pol delta whereas others affect both DNA replicases. The replicases and their accessory proteins appear to be highly conserved in eukaryotes, as homologous proteins have been found in species ranging from humans to yeast. (shrink)

Posterior parietal cortex has traditionally been considered to be a sensory association area in which higher-order processing and intermodal integration of incoming sensory information occurs. In this paper, evidence from clinical reports and from lesion and behavioral-electrophysiological experiments using monkeys is reviewed and discussed in relation to the overall functional organization of posterior parietal association cortex, and particularly with respect to a proposed posterior parietal mechanism concerned with the initiation and control of certain classes of eye and (...) limb movements. Preliminary data from studies of the effects of posterior parietal lesions on oculomotor control in monkeys are reported.The behavioral effects of lesions of posterior parietal cortex in monkeys have been found to be similar to those which follow analogous damage of the minor hemisphere in humans, while behavioral-electrophysiological experiments have disclosed classes of neurons in this area which have functional properties closely related to the behavioral acts that are disrupted by lesions of the area. On the basis of current data from these areas of study, it is proposed that the sensory association model of posterior parietal function is inadequate to account for the complexities of the present evidence. Instead, it now appears that many diverse neural mechanisms are locatedin partin parietal cortex, that some of these mechanisms are involved in sensory processing and perceptual functions, but that others participate in motor control, and that still others are involved in attentional, motivational, or emotional processes. It is further proposed that the elementary units of these various neural mechanisms are distributed within posterior parietal cortex according to the columnar hypothesis of Mountcastle. (shrink)

BL Features of the new edition: The translation has been completely rewritten, and the commentary thoroughly revised in the light of recent scholarship There is an additional glossary, and extended bibliography The Posterior Analytics contains some of Aristotle's most influential thoughts in logic, epistemology, metaphysics, and the philosophy of science. The first book expounds and develops the notions of a demonstrative argument and of a formal, axiomatized science; the second discusses a cluster of problems raised by the axioms or (...) principles of such a science, and investigates in particular the theory of definition. (shrink)

O autor analisa a posição de Antero de Quental perante o movimento iberista do século XIX, destacando a origem peninsular deste e a sua tradição, com raízes no liberalismo. Aponta a influência nesse movimento de um proudhonismo ingénuo, e destaca o papel de José Félix Henriques Nogueira como transmissor de um ideal federativo com base na concepção de uma "pátria espanhola comum", em que a federação tende no limite paraa fusão.A propósito conclui que a formulação dada por Antero (...) a este pensamento, em Portugal perante a Revolução de Espanha não é mais radical que a de Nogueira, antes é uma consequência contida no pensamento deste precursor do republicanismo. Por outro lado, Teófilo Braga, além de partilhar do ideal liberalista, advogou a separação dos Açores do continente português, contrariamente a Antero de Quental, que pensava que os açorianos só podiam ser portugueses, devendo entrar, federados com o Continente, num estado ibérico. /// L'auteur analyse la position de Antero de Quental devant le mouvement ibériste du XlX.e siècle, en mettant en relief son origine péninsulaire et sa tradition enracinée dans le libéralisme portugais. Il remarque l'influence sur ce mouvement d'un proudhonisme naïf et met en relief l'importance de José Félix Henriques Nogueira en tant que diffuseur d'un idéal fédératif basé sur la conception d'une "patrie espagnole commune", dans laquelle la fédération, à la limite, tend vers la fusion. À ce propos il remarque que la formulation donnée à cette pensée par Antero dans Portugal perante a Revolução de Espanha n'est pas plus radicale que celle de Nogueira; elle est plutôt une conclusion contenue dans la pensée de ce précurseur du républicanisme portugais. Par ailleurs, Teófilo Braga non seulement partagea l'idéal ibériste, mais il a été partisant de la séparation des Açores du Portugal continental, contrairement à Antero de Quental, qui jugeait que les Açoréens ne pourraient être que Portugais, et devraient entrer en fédération avec le Portugal ibérique dans un état péninsulaire. /// The author analises the position of Antero de Quental within the Iberist movement of the XlXth century and emphazises its Peninsular origin and its tradition with roots in the Portuguese Liberalism. He points to the influence in this movement of a certain naive proudhonism and the rêle of José Félix Henriques Nogueira as a transmitter of a federative ideal based on the conception of a "common Spanish fatherland" in which the federation tends at the limit towards fusion. In this context he concludes that the formulation given by Antero in the opuscule Portugal perante a Revolução de Espanha is no more radical than that of Nogueira; it is rather a consequence of the thought of that forerunner of the republicanism in Portugal. On the other hand Teófilo Braga not only shared the Iberist ideal, but also defended the separation of the Azores from the Portuguese homeland, contrarily to Antero de Quental, who thought that the Azoreans could only be Portuguese and that they should accede to an Iberian state federated with the mainland. (shrink)

For the second edition, the translation has been completely rewritten and the commentary has been thoroughly revised in the light of recent scholarship.

The first book of NE is organised on the model of investigating definitions described in the second Book of the Posterior Analytics, although, of course, with some adaptation due to the subject matter. It first establishes if the object exists and looks for the meaning of the terms used in common language to indicate it, next considers some necessary qualities of the object and then concludes with a definition of the object. We find there a dialectical syllogism of definition, (...) and not the procedure in three steps described in NE VII 1, sometimes called 'the method of ethics'. In fact, the method described in NE VII 1 does not apply to the first book of the NE. Its relevance for the NE has been somehow exaggerated. (shrink)

The Posterior Analytics contains some of Aristotle's most influential thoughts in logic, epistemology, metaphysics, and the philosophy of science. The first book expounds and develops the notions of a demonstrative argument and of a formal, axiomatized science, and investigates in particular the theory of definition. For the second edition of this volume, the translation has been completely rewritten; and the commentary, which is done with the needs of philosophical readers in mind, has been thoroughly revised in the light of (...) the scholarship of the last twenty years. (shrink)

I present the text at Posterior Analytics II.11, 94b8-26, offer a tentative translation, discuss the main construals offered in the literature, and argue for my own interpretation. Some of the general questions I discuss are the following: 1. What is the nature of the explanatory syllogisms offered as examples, especially in the case of the moving and the final cause? Are they scientific demonstrative explanations? In the case of the final cause, are they practical syllogisms? Are they productive? 2. (...) Are we to read into such examples Aristotle’s requirements from APo I.4-6 that demonstrative premisses and conclusions are universal, per se, and necessary? If so, in what way? If such requirements do not apply here, what are the implications for question 1? 3. What, if any, is the advantage of one type of causal explanation over another in cases in which there is causal competition between complementary explanations? 4. What is the relation between the thesis of this chapter, especially the section dedicated to the final cause, and the argument of II.8-10? How is essence related to causes? How is explanation/demonstration-based definition related to causal explanation in terms of the four causes? (shrink)

This paper revisits Aristotle’s discussion of akrasia in NE VII. 1–10. I try to offer a scientific reading of the book, according to which NE VII. 1–10 closely instantiates the main guidelines of Aristotle’s Posterior Analytics. I propose that NE VII. 1–2, which aims to establish the fact that akrasia exists, corresponds to the ὅτι-stage of an Aristotelian scientific inquiry, and NE VII. 3–10, which aims to explain both the cause and the object of akrasia, corresponds to the διότι-stage (...) of the inquiry. (shrink)

The Drosophila anterior‐posterior pattern genes of the terminal class, particularly the tailless gene, affect structures derived from the acron and the tail region of the embryo. These domains correspond in position and function to asegmental domains at the termini of annelids and more primitive insect embryos. This suggests that terminal genes in Drosophila may have originated in an ancestor common to both annelids and arthropods, and thus that the specification of termini in these metameric organisms is an ancient, evolutionarily (...) conserved process. (shrink)

Like most bilaterian animals, the annelid Platynereis dumerilii generates the majority of its body axis in an anterior to posterior temporal progression with new segments added sequentially. This process relies on a posterior subterminal proliferative body region, known as the "segment addition zone" (SAZ). We explored some of the molecular and cellular aspects of posterior elongation in Platynereis, in particular to test the hypothesis that the SAZ contains a specific set of stem cells dedicated to posterior (...) elongation.We cloned and characterized the developmental expression patterns of orthologs of 17 genes known to be involved in the formation, behavior, or maintenance of stem cells in other metazoan models. These genes encode RNA-binding proteins(e.g., tudor, musashi, pumilio) or transcription factors(e.g., myc, id, runx) widely conserved in eumetazoans. Most of these genes are expressed both in the migrating primordial germ cells and in overlapping ring-like patterns in the SAZ, similar to some previously analyzed genes(piwi, vasa). The SAZ patterns are coincident with the expression of proliferation markers cyclin B and PCNA. EdU pulse and chase experiments suggest that new segments are produced through many rounds of divisions from small populations of teloblast-like posterior stem cells. The shared molecular signature between primordial germ cells and posterior stem cells in Platynereis thus corresponds to an ancestral "stemness" program. (shrink)

In recent years the study of local religious histories, especially in Europe, has gained in prominence. Because of the encounters between different cultural traditions in the Middle Ages and the voyages of discovery, the religious history of the Iberian Peninsula became one of the most complex in Europe. This article focuses on one portion of this history around the turn of the 19th/20th century, and in particular on two attempts to blame the Catholic religion for the general crisis in Spain (...) and Portugal at the start of the modern era. These two forms of critiquing religion are illustrated by the examples of Miguel de Unamuno and Antero de Quental, whose writings were characteristic of the typical relationship between religion and intellectuals in this period. Not only were the Spanish philosopher and the Portuguese poet influential on their own and later generations, but they are also truly representative of a certain tragic ”loss“ of religion in the Iberian Peninsula. (shrink)

In the opening sentences of Book 2 of Posterior Analytics, Aristotle defines the four types of question that one can pose within the demonstrative science. In the edition by William D. Ross, the text reads as follows : τὰ ζητούμενά ἐστιν ἴσα τὸν ἀριθμὸν ὅσαπερ ἐπιστάμεθα. ζητοῦμεν δὲ τέτταρα, τὸ ὅτι, τὸ διότι, εἰ ἔστι, τί ἐστιν. ὅταν μὲν γὰρ πότερον τόδε ἢ τόδε ζητῶμεν, εἰς ἀριθμὸν θέντες, οἷον πότερον ἐκλείπει ὁ ἥλιος ἢ οὔ, τὸ ὅτι ζητοῦμεν. σημεῖον δὲ (...) τούτου· εὑρόντες γὰρ ὅτι ἐκλείπει πεπαύμεθα· καὶ ἐὰν ἐξ ἀρχῆς εἰδῶμεν ὅτι ἐκλείπει, οὐ ζητοῦμεν πότερον. ὅταν δὲ εἰδῶμεν τὸ ὅτι, τὸ διότι ζητοῦμεν, οἷον εἰδότες ὅτι ἐκλείπει καὶ ὅτι κινεῖται ἡ γῆ, τὸ διότι ἐκλείπει ἢ διότι κινεῖται ζητοῦμεν.The things we seek are equal in number to those we understand. We seek four things: the fact, the reason why, if it is, what it is. For when we seek whether it is this or this, putting it into a number, we seek the fact. Evidence for this: on finding that it is eclipsed we stop; and if from the start we know that it is eclipsed, we do not seek whether it is. When we know the fact we seek the reason why. (shrink)

Neuronal aggregates involved in conscious awareness are not evenly distributed throughout the CNS but comprise key components referred to as the neural network correlates of consciousness (NNCC). A critical node in this network is the posterior cingulate, precuneal, and retrosplenial cortices. The cytological and neurochemical composition of this region is reviewed in relation to the Brodmann map. This region has the highest level of cortical glucose metabolism and cytochrome c oxidase activity. Monkey studies suggest that the anterior thalamic projection (...) likely drives retrosplenial and posterior cingulate cortex metabolism and that the midbrain projection to the anteroventral thalamic nucleus is a key coupling site between the brainstem system for arousal and cortical systems for cognitive processing and awareness. The pivotal role of the posterior cingulate, precuneal, and retrosplenial cortices in consciousness is demonstrated with posterior cingulate epilepsy cases, midcingulate lesions that de-afferent this region and are associated with unilateral sensory neglect, observations from stroke and vegetative state patients, alterations in blood flow during sleep, and the actions of general anesthetics. Since this region is critically involved in self reflection, it is not surprising that it is similarly a site for the NNCC. Interestingly, information processing during complex cognitive tasks and during aversive sensations such as pain induces efforts to terminate self reflection and result in decreased processing in posterior cingulate and precuneal cortices. (shrink)

Aristotle, in Posterior Analytics B.10, separates three stages in scientific enquiry: knowledge of the signification of the relevant terms, knowledge of the existence of the kind, and knowledge of the essence of the kind. One can, in all relevant cases, achieve the first stage of enquiry without achieving the second or third stages. So, knowledge of the signification of the relevant terms does not essentially involve knowledge of the existence of the kind in question.

The first book of NE is organised on the model of investigating definitions described in the second Book of the Posterior Analytics, although, of course, with some adaptation due to the subject matter. It first establishes if the object exists and looks for the meaning of the terms used in common language to indicate it, next considers some necessary qualities of the object and then concludes with a definition of the object. We find there a dialectical syllogism of definition, (...) and not the procedure in three steps described in NE VII 1, sometimes called 'the method of ethics'. In fact, the method described in NE VII 1 does not apply to the first book of the NE. Its relevance for the NE has been somehow exaggerated. (shrink)