In this work, we question the ability of existing ranking-based semantics to capture persuasion settings, emphasising in particular the phenomena of procatalepsis and of fading. Some widely accepted principles of ranking-based semantics are incompatible with a faithful treatment of these phenomena, which means that no existing ranking-based semantics can capture these two principles together. This motivates us to introduce a new parametrized ranking-based semantics based on the notion of propagation which extends the existing propagation semantics 139–150) by adding an additional (...) parameter allowing us to gradually decrease the impact of arguments when the length of the path between two arguments increases. We show that this parameter gives the possibility of choosing if one wants to satisfy the property Void Precedence or not and to control the scope of the impact of the arguments. We also propose an experiment to show that the new semantics remains stable when this parameter varies and an axiomatic evaluation to compare it with existing ranking-based semantics in the literature. (shrink)

1. Argumentation consists in reasoning with conflicting information based on the exchange and evaluation of interacting arguments. It can be used for modelling dialogue (persuasion, negotiation), d...

The graph edit distance (GED) measures the dissimilarity between two graphs as the minimal cost of a sequence of elementary operations transforming one graph into another. This measure is fundamental in many areas such as structural pattern recognition or classification. However, exactly computing GED is NP-hard. Among different classes of heuristic algorithms that were proposed to compute approximate solutions, local search based algorithms provide the tightest upper bounds for GED. In this paper, we present K-REFINE and RANDPOST. K-REFINE generalizes and (...) improves an existing local search algorithm and performs particularly well on small graphs. RANDPOST is a general warm start framework that stochastically generates promising initial solutions to be used by any local search based GED algorithm. It is particularly efficient on large graphs. An extensive empirical evaluation demonstrates that both K-REFINE and RANDPOST perform excellently in practice. (shrink)

The norm of reciprocity has only been considered and experimentally demonstrated between two individuals. However, comments from several authors invite the consideration of an expanded form of this norm. 120 passersby, randomly assigned to 3 conditions, were asked to watch a confederate’s belongings. Depending on the condition, they had either previously been given a gift or not. In addition, the gift was offered by either the confederate making the target request or by a second confederate, not initially involved. First, results (...) show that passersby are significantly more likely to comply with the target request if they were offered a gift than if they weren’t no matter who the confederate was. Second, the confederate offering the gift gets significantly more compliance than the one not initially involved. Results are discussed in terms of self-presentation theory, internalization of norm and positive mood induction. (shrink)

Cancers rely on multiple, heterogeneous processes at different scales, pertaining to many biomedical fields. Therefore, understanding cancer is necessarily an interdisciplinary task that requires placing specialised experimental and clinical research into a broader conceptual, theoretical, and methodological framework. Without such a framework, oncology will collect piecemeal results, with scant dialogue between the different scientific communities studying cancer. We argue that one important way forward in service of a more successful dialogue is through greater integration of applied sciences (experimental and clinical) (...) with conceptual and theoretical approaches, informed by philosophical methods. By way of illustration, we explore six central themes: (i) the role of mutations in cancer; (ii) the clonal evolution of cancer cells; (iii) the relationship between cancer and multicellularity; (iv) the tumour microenvironment; (v) the immune system; and (vi) stem cells. In each case, we examine open questions in the scientific literature through a philosophical methodology and show the benefit of such a synergy for the scientific and medical understanding of cancer. (shrink)

In this article, we present findings from a participatory action research program in France on the exercise of human rights and supported and substitute decision-making, inspired by the United Nations Convention on the Rights of Persons with Disabilities (“CRPD”). Bringing together persons with the lived experience of disability, academics, and health and social care and support professionals, the project used the method of “experience-based construction of public problem” to transform experience into collective expertise. This enabled the exploration of support that (...) persons in vulnerable situations, whose capacity to exercise their human rights has weakened, need to make decisions in their lives and participate meaningfully in public debate. The relationship between the awareness of rights and exercise of rights is discussed. We argue for the need to balance out the positions of different contributors in participatory action research, in a reasoned manner, by recognizing the scientific and citizen-based participation of all partners. (shrink)

This study examines the multiple dimensions of the agdal system, a traditional Berber form of environmental management that regulates access to communal natural resources so as to allow the regeneration of natural resources. In fact, this ingenious system of agro-pastoral land rotation is ultimately beneficial for the conservation of the bio-physical environment, the performance of the present-day local economy and the maintenance of prevailing social cohesion and cultural coherence. Hence, agdals constitute a key element for the reinforcement of the sustainability (...) of existing agro-pastoral societies and ecosystems, but need to be better understood in order to explore necessary adaptations in the changing world of today. (shrink)

PREFACEProf. Göran Sundholm of Leiden University inspired the group of Logic at Lille and Valparaíso to start a fundamental review of the dialogical conception of logic by linking it to constructive type logic. One of Sundholm's insights was that inference can be seen as involving an implicit interlocutor. This led to several investigations aimed at exploring the consequences of joining winning strategies to the proof-theoretical conception of meaning. The leading idea is, roughly, that while introduction rules lay down the conditions (...) under which a winning strategy for the Proponent may be built, the elimination rules lay down those elements of the Opponent's assertions that the Proponent has the right to use for building winning strategy. It is the pragmatic and ethical features of obligations and rights that naturally lead to the dialogical interpretation of natural deduction.During the Visiting Professorship of Prof. Sundholm at Lille in (2012) the group of Lille started delving into the ways of implementing Per Martin-Löf's Constructive Type Theory with the dialogical perspective. In particular, Aarne Ranta's (1988) paper, the first publication on the subject, was read and discussed during Sundholm’s seminar. The discussions strongly suggested that the game-theoretical conception of quantifiers as deploying interdependent moves provide a natural link between CTT and dialogical logic. This idea triggered several publications by the group of Lille in collaboration with Nicolas Clerbout and Juan Redmond at the University of Valparaíso, including the publication of the book (2015) by Clerbout / Rahman that provides a systematic development of this way of linking CTT and the dialogical conception of logic. However the Clerbout / Rahman book was written from the CTT perspective on dialogical logic, rather than the other way round. The present book should provide the perspective from the other side of the dialogue between the Dialogical Framework and Constructive Type Theory. The main idea of our present study is that Sundholm's (1997) notion of epistemic assumption is closely linked to the Copy-Cat Rule or Socratic Rule that distinguishes the dialogical framework from other game-theoretical approaches. One way to read the present book is as a further development of Sundholm’s extension of Austin's (1946, p. 171) remark on acts of assertion to inference. Indeed, Sundholm (2013, p. 17) gave the following forceful formulation: When I say therefore, I give others my authority for asserting the conclusion, given theirs for asserting the premisses.Per Martin-Löf, in recent lectures, have utilized the dialogical perspective on epistemic assumptions to get out of a certain circle that threatens the explanation of the notions of inference and demonstration. A demonstration may be explained as a chain of (immediate) inferences starting from no premisses. That an inference J1... Jn—————Jis valid means that the conclusion J can be made evident on the assumption that J1, …, Jn are known. The notion of epistemic assumption thus enters in the explanation of valid inference. We cannot, however, in this explanation understand 'known' in the sense of demonstrated, for then we are explaining the notion of inference in terms of demonstration, whereas demonstration has been explained in terms of inference. Martin-Löf suggests that we here understand 'known' in the sense of asserted, so that epistemic assumptions are judgements others have made, judgements for which others have taken the responsibility; that the inference is valid then means that, given that others have taken responsbility for the premisses, I can take responsibility for the conclusion:The circularity problem is this: if you define a demonstration to be a chain of immediate inferences, then you are defining demonstration in terms of inference. Now we are considering an immediate inference and we are trying to give a proper explanation of that; but, if that begins by saying: Assume that J1, …, Jn have been demonstrated – then you are clearly in trouble, because you are about to explain demonstration in terms of the notion of immediate inference, hence when you are giving an account of the notion of immediate inference, the notion of demonstration is not yet at your disposal. So, to say: Assume that J1, …, Jn have already been demonstrated, makes you accusable of trying to explain things in a circle. The solution to this circularity problem, it seems to me now, comes naturally out of this dialogical analysis. […]The solution is that the premisses here should not be assumed to be known in the qualified sense, that is, to be demonstrated, but we should simply assume that they have been asserted, which is to say that others have taken responsibility for them, and then the question for me is whether I can take responsibility for the conclusion. So, the assumption is merely that they have been asserted, not that they have been demonstrated. That seems to me to be the appropriate definition of epistemic assumption in Sundholm's sense. One of the main tenets of the present study is that the further move of relating the Socratic Rule rule with judgemental equality provides both a simpler and more direct way to implement the constructive type theoretical approach within the dialogical framework. Such a reconsideration of the Socratic Rule, roughly speaking, amounts to the following. 1.A move from P that brings-forward a play-object in order to defend an elementary proposition A can be challenged by O. 2.The answer to such a challenge, involves P bringing forward a definitional equality that expresses the fact that the play-object chosen by P copies the one O has chosen while positing A. For short, the equality expresses at the object-languaje level that the defence of P relies on the authority given to O to be able to produce the play-objects she brings forward. More generally, according to this view, a definitional equality established by P and brought forward while defending the proposition A, expresses the equality between a play-object (introduced by O) and the instruction for building a play-object deployed by O while affirming A. So it can be read as a computation rule that indicates how to compute O's instructions. Let us recall that from the strategic point of view, O's moves correspond to elimination rules of demonstrations. Thus, the dialogical rules that prescribe how to introduce a definitional equality – correspond – at the strategic level – to the definitional equality rules for CTT as applied to the selector-functions involved in the elimination rules. So, what we are doing here is extending the dialogical interpretation of Sundholm's epistemic assumption to the rules that set up the definitional equality of a type.The present work is structured in the following way:•In the Introduction we state the main tenets that guide our book•Chapter II contains a brief overview of Constructive Type Theory penned by Ansten Klev with exercises and their solutions. •Chapter III offers a novel presentation of the dialogical conception of logic. In fact, the first two sections of the chapter provide an overview of standard dialogical logic – including solved exercises, slightly adapted to the content of the present volume. The rest of the sections develop a new dialogical approach to Constructive Type Theory. •Chapters IV and V contain the main body of our study, namely the relation between the Socratic Rule, epistemic assumptions, and equality. The chapter provides the reader with thoroughly worked out examples with comments. •After the Final Remarks the book containsa.An appendix containing a an overview of all the rules for the new formulation of dialogical approach to constructive type theory developed in the book; b.a brief outline of Per Martin-Löf's informal presentation of the demonstration of the axiom of choice.c.two examples of a tree-shaped graph of an extensive strategy. Acknowledgments: Many thanks to Mark van Atten (Paris1), Giuliano Bacigalupo (Zürich), Charles Zacharie Bowao (Univ. Ma Ngouabi de Brazzaville, Congo), Christian Berner (Lille3), Michel Crubellier (Lille3), Pierre Cardascia (Lille3), Oumar Dia (Dakar), Marcel Nguimbi ((Univ. Marien Ngouabi de Brazzaville, Congo), Adjoua Bernadette Dango (Lille3 / Alassane Ouattara de Bouaké, Côte d'Ivoire), Steephen Rossy Eckoubili (Lille3), Johan Georg Granström (Zürich), Gerhard Heinzmann (Nancy2), Muhammad Iqbal (Lille3), Matthieu Fontaine (Lille3), Radmila Jovanovic (Belgrad), Hanna Karpenko (Lille3), Laurent Keiff (Lille3), Sébastien Magnier (Saint Dennis, Réunion), Clément Lion (Lille3), Gildas Nzokou (Libreville), Fachrur Rozie (Lille3), Helge Rückert (Mannheim), Mohammad Shafiei (Paris1), and Hassan Tahiri (Lisbon), for rich interchanges, suggestions on the main claims of the present study and proof-reading of specific sections of the text. Special thanks to Gildas Nzokou (Libreville), Steephen Rossy Eckoubili (Lille3) and Clément Lion (Lille3), with whom a Pre-Graduate Textbook in French on dialogical logic and CTT is in the process of being worked out – during the visiting-professorship in 2016 of the former. Eckoubili is the author of the sections on exercises for dialogical logic, Nzokou cared of those involving the development of CTT-demonstrations out of winning-strategies. Special thanks also to Ansten Klev (Prague) for helping with technical details and conceptual issues on CTT, particularly so as author of the chapter introducing CTT. (shrink)

The field of neuroimaging has reached a watershed. Brain imaging research has been the source of many advances in cognitive neuroscience and cognitive science over the last decade, but recent critiques and emerging trends are raising foundational issues of methodology, measurement, and theory. Indeed, concerns over interpretation of brain maps have created serious controversies in social neuroscience, and, more important, point to a larger set of issues that lie at the heart of the entire brain mapping enterprise. In this volume, (...) leading scholars -- neuroimagers and philosophers of mind -- reexamine these central issues and explore current controversies that have arisen in cognitive science, cognitive neuroscience, computer science, and signal processing. The contributors address both statistical and dynamical analysis and modeling of neuroimaging data and interpretation, discussing localization, modularity, and neuroimagers' tacit assumptions about how these two phenomena are related; controversies over correlation of fMRI data and social attributions ; and the standard inferential design approach in neuroimaging. Finally, the contributors take a more philosophical perspective, considering the nature of measurement in brain imaging, and offer a framework for novel neuroimaging data structures. Contributors: William Bechtel, Bharat Biswal, Matthew Brett, Martin Bunzl, Max Coltheart, Karl J. Friston, Joy J. Geng, Clark Glymour, Kalanit Grill-Spector, Stephen José Hanson, Trevor Harley, Gilbert Harman, James V. Haxby, Rik N. Henson, Nancy Kanwisher, Colin Klein, Richard Loosemore, Sébastien Meriaux, Chris Mole, Jeanette A. Mumford, Russell A. Poldrack, Jean-Baptiste Poline, Richard C. Richardson, Alexis Roche, Adina L. Roskies, Pia Rotshtein, Rebecca Saxe, Philipp Sterzer, Bertrand Thirion, Edward Vul The hardcover edition does not include a dust jacket. (shrink)

Artificial intelligence and robots may progressively take a more and more prominent place in our daily environment. Interestingly, in the study of how humans perceive these artificial entities, science has mainly taken an anthropocentric perspective (i.e., how distant from humans are these agents). Considering people’s fears and expectations from robots and artificial intelligence, they tend to be simultaneously afraid and allured to them, much as they would be to the conceptualisations related to the divine entities (e.g., gods). In two experiments, (...) we investigated the proximity of representation between artificial entities (i.e., artificial intelligence and robots), divine entities and natural entities (i.e., humans and other animals) at both an explicit (Study 1) and an implicit level (Study 2). In the first study, participants evaluated these entities explicitly on positive and negative attitudes. Hierarchical clustering analysis showed that participants’ representation of artificial intelligence, robots and divine entities were similar, while the representation of humans tended to be associated with that of animals. In the second study, participants carried out a word/non-word decision task including religious semantic-related words and neutral words after the presentation of a masked prime referring to divine entities, artificial entities and natural entities (or a control prime). Results showed that after divine and artificial entity primes, participants were faster to identify religious words as words compared to neutral words arguing for a semantic activation. We conclude that people make sense of the new entities by relying on already familiar entities and in the case of artificial intelligence and robots, people appear to draw parallels to divine entities. (shrink)

According to philosophers like James Weinstein, our democratic values give us a compelling reason to tolerate hate speech. In fact, they argue that even if hate speech causes significant harms, our democratic values nonetheless sometimes call for a hands-off approach. In particular, they evoke the democratic value of citizens being free to criticize and voice dissent towards the laws that bind them. This paper seeks to establish two key points. First, that upon closer examination, the kind of arguments that Weinstein (...) presents against hate speech regulation is less than convincing. Secondly, that by building on Weinstein's discussion of the concept of viewpoint discrimination, we can construct a more convincing objection to hate speech regulation. That said, this more convincing objection falls short of calling for the abolition of all hate speech regulation, instead highlighting the need for transparency and consistency in the way governments regulate harmful speech. (shrink)

Now characterised by high-throughput sequencing methods that enable the study of microbes without lab culture, the human “microbiome” (the microbial flora of the body) is said to have revolutionary implications for biology and medicine. According to many experts, we must now understand ourselves as “holobionts” like lichen or coral, multispecies superorganisms that consist of animal and symbiotic microbes in combination, because normal physiological function depends on them. Here I explore the 1960s research of biologist René Dubos, a forerunner figure mentioned (...) in some historical accounts of the microbiome, and argue that he arrived at the superorganism concept 40 years before the Human Microbiome Project. This raises the question of why his contribution was not hailed as revolutionary at the time and why Dubos is not remembered for it. (shrink)

Dans ce livre, Malebranche expose sa philosophie à travers des entretiens avec un philosophe, un janséniste et un mandarin chinois. Il explore les différentes dimensions de la métaphysique, de la religion et de la mort et cherche à répondre aux questions fondamentales de l'existence. Tout étudiant en philosophie trouvera ce livre intéressant et instructif. This work has been selected by scholars as being culturally important, and is part of the knowledge base of civilization as we know it. This work is (...) in the "public domain in the United States of America, and possibly other nations. Within the United States, you may freely copy and distribute this work, as no entity (individual or corporate) has a copyright on the body of the work. Scholars believe, and we concur, that this work is important enough to be preserved, reproduced, and made generally available to the public. We appreciate your support of the preservation process, and thank you for being an important part of keeping this knowledge alive and relevant. (shrink)

Object identification via a perceptual-demonstrative mode of presentation has been studied in cognitive science as a particularly direct and context-dependent means of identifying objects. Several recent works in cognitive science have attempted to clarify the relation between attention, demonstrative identification and context exploration. Assuming a distinction between ‘ demonstrative reference' and ‘perceptual-demonstrative identification', this article aims at specifying the role of attention in the latter and in the linking of conceptual and non conceptual contents while exploring a spatial context. First, (...) the analysis presents an argument to the effect that selection by overt and covert attention is needed for perceptual-demonstrative identification since overt/covert selective attention is required for the situated cognitive access to the target object. Second, it describes a hypothesis that makes explicit some of the roles of attention: the hypothesis of identification by epistemic attention via the control of perceptual routines. (shrink)

This essay explores the research practice of French geometer Michel Chasles, from his 1837 Aperçu historique up to the preparation of his courses on ‘higher geometry’ between 1846 and 1852. It argues that this scientific pursuit was jointly carried out on a historiographical and a mathematical terrain. Epistemic techniques such as the archival search for and comparison of manuscripts, the deconstructive historiography of past geometrical methods, and the epistemologically motivated periodization of the history of mathematics are shown to have played (...) a crucial role in the shaping of Chasles's own theories. In particular, we present Chasles's approach to the ‘material history’ of algebraic symbolism and argue that it motivated and informed his subsequent invention of a novel notational technology for the writing of geometrical proofs and propositions. In return, this technology allowed Chasles to carry out a programme for the modernization of geometry in keeping with epistemic requirements he had also delineated via a form of historical writing. (shrink)

Belief merging aims at combining several pieces of information coming from different sources. In this paper we review the works on belief merging of propositional bases. We discuss the relationship between merging, revision, update and confluence, and some links between belief merging and social choice theory. Finally we mention the main generalizations of these works in other logical frameworks.

Animals who live in cities must coexist with us. They are, as a result, entitled to the conditions of their flourishing. This article argues that, as the boundaries of cities and urban areas expand, the boundaries of our conception of captivity should expand too. Urbanization can undermine animals’ freedoms, hence their ability to live good lives. I draw the implications of an account of “pervasive captivity” against the background of the Capabilities Approach. I construe captivity, including that of urban animals, (...) as affecting a range of animal capabilities, understood as freedoms, and I address some tensions within Nussbaum’s treatment of human-animal conflicts. Using the Capabilities Approach as a guide, I will attempt to motivate a convergence between habitat preservation in urbanized environments, urban design guided by justice, and the individual freedoms of animals. (shrink)

To circumvent both historicism and utopianism, Reiner Schürmann develops an account of a three-tiered temporal difference in which the entitative and the event-like are connected by an “economy of presence.” This paper investigates Schürmann’s notion of “economy” to draw out the historical-systematic status of what he construes as “economic anarchy” in distinction from both Giorgio Agamben’s idea of a “true anarchy” purged of all oikonomia and from Miguel Vatter’s rights-based notion of “politico-legal anarchy.” What is at stake in “economic anarchy” (...) is the preparation of a place that puts an end to domination by first principles without fantasizing a clean cut that ends up reproducing hegemonic fantasms. Rather, Schürmann insists on the aporetic and incongruous nature of that “caesura-place” in which the synchronic and the diachronic, universalization and singularization, are bound together. At variance with both Agamben’s appeal to a destituent potential and Vatter’s assertion of constituent power, Schürmann draws out the discordance of times that is implied by what he calls originary or individual practice. The paper concludes with a brief confrontation of Schürmann’s critique of epochal economy with a Marxian critique of political economy. (shrink)

Le dernier étage de l’ Aufbau de Carnap est occupé par le type des objets culturels . L’examen des remarques fugitives de Carnap et la formulation des embarras ou des lacunes qu’elles manifestent montrent notamment, de l’intérieur, les faiblesses du cadre extensionnaliste en ce qui concerne la compréhension des objets culturels. La mention comparative de certains essais phénoménologiques d’ontologie des objets culturels suggère d’autres voies .The last floor of the Carnap's Aufbau by is inhabited by the type of cultural objects (...) . The examination of Carnap's brief remarks and the formulation of the embarrassments or the lacunas they exhibit show, from within, the weaknesses of the extensionalist framework for the comprehension of cultural objects. The comparative mention of phenomenological attempts at an ontology of cultural objects suggests other ways of handling them. (shrink)

This article has two purposes: first, to describe some archival discoveries about Nicod’s family background, academic development and political life; and second, to publish and comment on a newly discovered article by Nicod about Russell. This article acclaims not only Russell’s achievements in logic and philosophy—as one might expect from such a devoted protégé as Nicod—but also (albeit only in glimpses permitted by France’s wartime censorship) his anti-war politics and writings. As the reader will realize, the two objectives are connected: (...) what the archives reveal and what the article illustrates is a hitherto underappreciated level of political awareness and pacifist commitment in Nicod. (shrink)

High and low alexithymia scorers were confronted with a modified visual oddball task that allowed the study of categorical perception of emotional expressions on faces. Participants had to quickly detect a deviant (rare) morphed face that shared or did not share the same emotional expression as the frequent one. Expected categorical perception effects, which were also neurophysiologically indexed, showed that rare stimuli were detected faster if they depicted a different emotional expression compared to rare stimuli depicting the same emotional expression (...) than the frequent one. Even if no differences were observed at a behavioural level, high alexithymia scorers evidenced overall delayed neurophysiological responses in components related to the attentional processing of rare emotional faces. Moreover, the categorical perception effects for event-related components associated with the attentional processing were smaller in high alexithymia scorers and were even absent for anger. These results show that high alexithymia scorers present discrimination delays that are already observed at the attentional level. (shrink)

This study investigates the social–psychological mechanisms leading individuals in organizations to engage in environmental citizenship behaviors, which entail keeping abreast of, and participating in, the environmental affairs of a company. Informed by the corporate greening and organizational behavior literature, we suggested that an employee’s level of involvement in the management of a company’s environmental impact was the overt manifestation of his or her discretionary sense of commitment to environmental concerns in the work context, and that such commitment developed through the (...) interplay of individual, organizational, and supervisory factors. Our general findings support the idea that when environmental protection is valued and encouraged by the company and line managers, organization members are more likely to experience a volitional sense of attachment and responsibility to corporate environmental goals and values, which is enacted through citizenship behaviors. We also expected that individual ecological beliefs would strengthen the environmental commitment of employees via identification with, and adherence to, the socially responsible cause embodied by the organization and its managerial staff. But it did not. On the contrary, the data indicated that corporate environmental policy is more likely to influence an employee’s level of environmental commitment when he or she holds weak versus strong personal ecological beliefs. Theoretical and managerial implications of our findings are discussed. (shrink)

Written seven years after publication of his Search after Truth, Malebranche's Treatise on Ethics develops a detailed, experimental science of ethics in two parts - the ethics of virtue and the ethics of duty.

Virtual reality allows the user to be immersed in environments in which they can experience situations and social interactions from different perspectives by means of virtual embodiment. In the context of rehabilitation of violent behaviors, a participant could experience a virtual violent confrontation from different perspectives, including that of the victim and bystanders. This approach and other virtual scenes can be used as a useful tool for the rehabilitation of intimate partner violence perpetrators, through improvement of their empathic skills or (...) for training in non-violent responses. In this perspective, we revise and discuss the use of this tool in a prison environment for the rehabilitation of IPV perpetrators with a particular focus on practical aspects based on our experience. (shrink)

Syllogisms (e.g. “All A are B; All B are C; What is true about A and C?”) are a long‐studied area of human reasoning. Riesterer, Brand, and Ragni compare a variety of models to human performance and show that not only do current models have a lot of room for improvement, but more importantly a large part of this improvement must come from examining individual differences in performance.