Etimologicamente, epistemologia significa discurso (logos) sobre a ciência e, em um sentido amplo, pode ser conceituada como o estudo metódico e reflexivo da ciência, de sua organização, de sua formação, do seu funcionamento e produtos intelectuais. Em função do evidente crescimento da produção científica brasileira em torno do biodiesel, verifica-se a necessidade de um estudo de natureza epistemológica desta produção, pois é uma maneira de se observar e avaliar a qualidade do que está sendo produzido. O presente trabalho propõe uma discussão de natureza epistemológica sobre artigos de autoria brasileira, relacionados ao assunto biodiesel, publicados em periódicos internacionais no período de janeiro de 2000 a junho de 2011. Com este trabalho, do tipo exploratório-descritivo, foi possível reconhecer e identificar o que está sendo pesquisado a respeito do biodiesel no Brasil e quais as tendências temáticas e metodológicas que estão sendo usadas, além de determinar como vem se desenvolvendo o conhecimento ao longo dos anos constituintes do intervalo de tempo considerado. Para realização desta pesquisa, optou-se por uma abordagem do tipo teórico-empírica e, a pesquisa documental seguida de uma análise crítica, como estratégias de pesquisa. Os resultados mostram que é significativa a quantidade de artigos produzidos por pelo menos um autor filiado ao Brasil, especialmente a partir do ano 2008, quando se deu a obrigatoriedade do uso do biocombustível no país. No entanto, é patente a escolha, de certo modo recorrente, de um padrão de pesquisa durante a condução destes trabalhos, tanto na seleção dos temas e formulação das propostas, como também na opção pelas abordagens metodológicas utilizadas. Foram encontrados muitos estudos com propostas e estruturas semelhantes. A maior parte dos artigos amostrados é do tipo empírico-positivista e faz uso do delineamento experimental para tratar de métodos, técnicas e processos químicos para produção do biodiesel. Pode-se dizer que, de uma maneira geral, tais estudos exercem sua contribuição para o desenvolvimento científico, mas ainda há muito para ser pesquisado. Para uma evolução da produção científica a respeito do biodiesel, é necessário que se procure inovar nas escolhas das estratégias e abordagens metodológicas utilizadas, bem como despender maior cuidado na formulação dos problemas e objetivos das pesquisas. A qualidade dos estudos pode e deve ser aprimorada, especialmente se a intenção implica aproveitar os resultados dessas pesquisas para que se consiga solucionar os problemas ainda vigentes, relacionados à consolidação do uso do biocombustível no país. / Etymologically, epistemology means speech (logos) of the Science and, in a wide sense, may be conceived as the methodic and reflexive study of science, its organization, its formation, its functioning and intellectual products. Owing to the clear growth of the Brazilian scientific production about biodiesel, it is noticed the necessity of an epistemological study of this production since it is a way to observe and evaluate the quality of what is being produced. This paper proposes an epistemological discussion about Brazilian authorship articles related to biodiesel published on international journals from January 2000 to June 2011. With this exploratory-descriptive paper, it has been possible to recognize and identify what is being researched about biodiesel in Brazil and what thematic and methodological trends are being used, besides to determine how knowledge has been developing along the constituent years of the considered time interval. In order to carry out this research the option has been for a theoretical empirical approach and the inquiry followed by a critical analysis as research strategies. The results show that it is significant the number of articles produced by at least one author associated with Brazil, particularly from 2008 on when the use of biofuel became mandatory in the country. However, it is evident the choice, some way recurrent, of a research pattern during the leading of these works, not only concerning the selection of the themes and formulation of the proposals, but also on the options for the methodological approaches used. Many studies have been found with similar proposals and structures. Most part of the sampled articles are of empirical positivist type and it uses the experimental delineation to deal with the methods, techniques and chemical processes for the biodiesel production. It may be said that altogether, such studies contribute to the scientific development but there is still much to be researched. In order to reach an evolution of the scientific production of the biodiesel, it is necessary to innovate in choices of the strategies and methodological approaches used as well as to take greater care on the formulation of the matters and targets of the researches. The quality of the studies may and should be perfected, especially if the intention implies to improve the results of these researches to solve the current matters related to the consolidation of the use of biofuel in the country.

Submitted by admin tede (tede@pucgoias.edu.br) on 2018-02-06T16:38:35Z No. of bitstreams: 1 PRISCILA OLIVEIRA DA COSTA VILAR.pdf: 582158 bytes, checksum: 3a5f21f2e13188b74de74f5b8bd4db41 (MD5) / Made available in DSpace on 2018-02-06T16:38:35Z (GMT). No. of bitstreams: 1 PRISCILA OLIVEIRA DA COSTA VILAR.pdf: 582158 bytes, checksum: 3a5f21f2e13188b74de74f5b8bd4db41 (MD5) Previous issue date: 2001-06-01 / The present study intends to investigate how physical educational teachers learners mediate children’s development processes during school activities. Based on historic-cultural perspective the study focuses on qualitative epistemology analysis as a methodological approach. Research starts from ESEFEGO’s curriculum investigation to the confronts within practice by the use of participant observation and interview over a semester, involving two teachers learners from that institution supervised on their practice at school in 1999. Considerations emphasize changes that occur in teachers learners’ planning during class activities and in the relationship between themselves and the children involved in activities such as their considerations on practice. Furthermore the study points to some paradoxes between academic learning and reconstruction throughout practice and repercussions of these factors within children psychological development. / A presente investigação teve como principal objetivo o estudo de como a formação teórico-prática do Professor de Educação Física atua como mediadora dos processos de desenvolvimento psicológico da criança durante a prática da Educação Física Escolar. Tendo como principal referência a abordagem sócio-histórica-cultural e, utilizando uma metodologia engendrada a partir dos fundamentos da Epistemologia Qualitativa, o estudo parte da análise dos próprios currículos da ESEFEGO até o confronto com a prática através da observação, participação e realização de entrevistas durante um semestre de estágio supervisionado de duas estagiárias desta instituição no ano de 1999. Dentre as considerações que puderam ser feitas ao final do trabalho, destacam-se as que se referem às mudanças que ocorriam no planejamento e relacionamento das professoras estagiárias, tanto entre si como delas com as crianças, durante o movimento das aulas e da reflexão da própria prática durante as entrevistas, apontando, alguns paradoxos entre o que era academicamente aprendido e o que na prática era reconstruído, além das repercussões destes fatores no desenvolvimento psicológico das crianças.

Orientador: Adolfo Ramos Lamar. / Dissertação (mestrado) - Universidade Regional de Blumenau, Centro de Ciências da Educação, Programa de Pós-Graduação em Educação.

Orientador: Adolfo Ramos Lamar. / Dissertação (mestrado) - Universidade Regional de Blumenau, Centro de Ciências da Educação, Programa de Pós-Graduação em Educação.

Orientador: Adolfo Ramos Lamar. / Dissertação (mestrado) - Universidade Regional de Blumenau, Centro de Ciências da Educação, Programa de Pós-Graduação em Educação.

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Jean Piaget desenvolveu, a partir dos anos 60, uma teoria de adaptação e evolução das especies que unifica o todo o funcionamento do organismo, desde seu comportamento ate as modificacoes geneticas, sob um paradigma cibernetico e interativo. Tal modelo, ignorado a epoca, tem se mostrado cada vez mais coerente com as descobertas da Biologia Moderna. Este trabalho procura mostrar a congruencia do modelo de Piaget as evidencias levantadas Biologia do seculo XXI e extrair dai algumas consequência para a Psicologia e para outras areas do conhecimento e da ação humanas / Jean Piaget developed, from the sixties onward, a theory for adaptation and evolution of species that unifies under a cybernetic and interactive paradigm the entire living being functioning, from the behavior to the genetic modifications. This model, ignored at the time, has become ever more consistent with the findings of modern biology. This work aims to show the congruence of Piaget\'s model to the evidence raised Biology of the XXI century and then extract some consequence for psychology and other areas of knowledge and human action

Orientador: Irineu Bicudo / Banca: José Rodrigues Seabra Filho / Banca: Renata Cristina Geromel Meneghetti / Banca: Marcos Vieira Teixeira / Banca: Inocêncio Fernandes Balieiro Filho / Resumo: O objetivo dessa tese é investigar a relação entre matemática e filosofia em três obras de Platão: o Mênon, o Fédon e A República. Busca-se com isso esclarecer, primeiramente, a influência da matemática no desenvolvimento da filosofia, e, depois, o efeito desta na evolução metodológica daquela, principalmente no que diz respeito ao método analítico, ou hipotético. A pesquisa é norteada pelos testemunhos de Proclus em seus Comentários ao Livro I dos Elementos de Euclides, onde o nome de Platão é associado ao método. Em seguida, verifica-se a descrição dos métodos da análise e síntese feita por Pappus de Alexandria em sua Coleção matemática, a partir da qual são procurados nos diálogos os elementos precursores. A interpretação dos trechos matemáticos dos textos platônicos apoiase nos testemunhos e fragmentos de Hipócrates de Quios, Filolau de Crotona e Árquitas de Tarento, elaborando assim um quadro geral do estado da arte das ciências matemáticas nos séculos V-VI a.C. O seu intuito foi o de contextualizar as principais questões da matemática que teriam atraído o interesse de Platão, levando-o a valer-se da matemática como paradigma metodológico e heurístico a ser adaptado à filosofia. Apresentando uma inovação didática envolta por problemas da imprecisão da linguagem, Platão reformula as doutrinas présocráticas combinadas ao pensamento matemático, cujos desdobramentos são essenciais à organização aristotélica e à formalização Euclidiana / Abstract: The objective of this thesis is to investigate the relationship between mathematics and philosophy in three Plato‟s work: the Meno, the Phaedo and the Republic. Searching with this to clarify, first, the influence of mathematics in the philosophy‟s development, and then, the effect of this one on the methodological development of that, especially with regard to the analytical or hypothetical method. The research is guided by the Proclus testimony in his Commentary On The First Book of Euclid's Element, where the name of Plato is associated with the method. Hereupon, is checked the description of the methods of analysis and synthesis made by Pappus of Alexandria in his Mathematical Collection, from which is searched the precursor elements on the dialogues. The interpretation of the mathematical passages of the Platonic texts are based on testimonies and fragments of Hippocrates of Chios, Philolaus of Croton, and Archytas of Tarentum, thus elaborating a general picture of the mathematical sciences state of the art in the centuries V-VI BC. Its scope was to contextualize the main issues of the mathematics that have attracted the Plato‟s interest and that led him to avail himself of that science as a methodological and heuristic paradigm to be adapted to the philosophy. Featuring a didactic innovation surrounded by the imprecision of language problems, Plato reformulates the pre-Socratic doctrines combined to the mathematical thinking, whose developments are essential to Aristotelian organization and Euclidean formalization / Doutor

This is a contribution to combinatorial set theory, specifically to infinite Ramsey Theory, which deals with partitions of infinite sets. The basic pigeon hole principle states that for every partition of the set of all natural numbers in finitely many classes there is an infinite set of natural numbers that is included in some one class. Ramsey’s Theorem, which can be seen as a generalization of this simple result, is about partitions of the set [N]k of all k-element sets of natural numbers. It states that for every k ≥ 1 and every partition of [N]k into finitely many classes, there is an infinite subset M of N such that all k-element subsets of M belong to some same class. Such a set is said to be homogeneous for the partition. In Ramsey’s own formulation (Ramsey, [8], p.264), the theorem reads as follows. Theorem (Ramsey). Let Γ be an infinite class, and μ and r positive numbers; and let all those sub-classes of Γ which have exactly r numbers, or, as we may say, let all r−combinations of the members of Γ be divided in any manner into μ mutually exclusive classes Ci (i = 1, 2, . . . , μ), so that every r−combination is a member of one and only one Ci; then assuming the axiom of selections, Γ must contain an infinite sub-class △ such that all the r−combinations of the members of △ belong to the same Ci. In [5], Neil Hindman proved a Ramsey-like result that was conjectured by Graham and Rotschild in [3]. Hindman’s Theorem asserts that if the set of all natural numbers is divided into two classes, one of the classes contains an infinite set such that all finite sums of distinct members of the set remain in the same class. Hindman’s original proof was greatly simplified, though the same basic ideas were used, by James Baumgartner in [1]. We will give new proofs of these two theorems which rely on forcing arguments. After this, we will be concerned with the particular partial orders used in each case, with the aim of studying its basic properties and its relations to other similar forcing notions. The partial order used to get Ramsey’s Theorem will be seen to be equivalent to Mathias forcing. The analysis of the partial order arising in the proof of Hindmans Theorem, which we denote by PFIN, will be object of the last chapter of the thesis. A summary of our work follows. In the first chapter we give some basic definitions and state several known theorems that we will need. We explain the set theoretic notation used and we describe some forcing notions that will be useful in the sequel. Our notation is generally standard, and when it is not it will be sufficiently explained. This work is meant to be self-contained. Thus, although most of the theorems recorded in this first, preliminary chapter, will be stated without proof, it will be duly indicated where a proof can be found. Chapter 2 is devoted to a proof of Ramsey’s Theorem in which forcing is used to produce a homogeneous set for the relevant partition. The partial order involved is isomorphic to Mathias forcing. In Chapter 3 we modify Baumgartner’s proof of Hindman’s Theorem to define a partial order, denoted by PC , from which we get by a forcing argument a suitable homogeneous set. Here C is an infinite set of finite subsets of N, and PC adds an infinite block sequence of finite subsets of natural numbers with the property that all finite unions of its elements belong to C. Our proof follows closely Baumgartner’s. The partial order PC is similar both to the one due to Matet in [6] and to Mathias forcing. This prompts the question whether it is equivalent to one of them or to none, which can only be solved by studying PC , which we do in chapter 4. In chapter 4 we first show that the forcing notion PC is equivalent to a more manageable partial order, which we denote by PFIN. From a PFIN- generic filter an infinite block sequence can be defined, from which, in turn, the generic filter can be reconstructed, roughly as a Mathias generic filter can be reconstructed from a Mathias real. In section 4.1 we prove that PFIN is not equivalent to Matet forcing. This we do by showing that PFIN adds a dominating real, thus also a splitting real (see [4]). But Blass proved that Matet forcing preserves p-point ultrafilters in [2], from which follows that Matet forcing does not add splitting reals. Still in section 4.1 we prove that PFIN adds a Mathias real by using Mathias characterization of a Mathias real in [7] according to which x ⊆ ω is a Mathias real over V iff x diagonalizes every maximal almost disjoint family in V . In fact, we prove that if D = (Di)i∈ω is the generic block sequence of finite sets of natural numbers added by forcing with PFIN, then both {minDi : i ∈ ω} and {maxDi : i ∈ ω} are Mathias reals. In section 4.2 we prove that PFIN is equivalent to a two-step iteration of a σ-closed and a σ-centered forcing notions. In section 4.3 we prove that PFIN satisfies Axiom A and in section 4.4 that, as Mathias forcing, it has the pure decision property. In section 4.5 we prove that PFIN does not add Cohen reals. So far, all the properties we have found of PFIN are also shared by Mathias forcing. The question remains, then, whether PFIN is equivalent to Mathias forcing. This we solve by first showing in section 5.1 that PFIN adds a Matet real and then, in section 5.2, that Mathias forcing does not add a Matet real, thus concluding that PFIN and Mathias forcing are not equivalent forcing notions. In the last, 5.3, section we explore another forcing notion, denoted by M2, which was introduced by Shelah in [9]. It is a kind of “product” of two copies of Mathias forcing, which we relate to denoted by M2. Bibliography [1] J.E. Baumgartner. A short proof of Hindmanʼs theorem. Journal of Combinatorial Theory, 17:384–386, 1974. [2] A. Blass. Applications of superperfect forcing and its relatives. In Set theory and its applications. Lecture notes in Mathematics. Springer, Berlin., 1989. [3] R.L. Graham and B. L. Rothschild. Ramseyʼs theorem for n-parameter sets. Transaction American Mathematical Society, 159:257–292, 1971. [4] L. Halbeisen. A playful approach to Silver and Mathias forcing. Studies in Logic (London), 11:123142, 2007. [5] N. Hindman. Finite sums from sequences within cells of partition of N. Journal of Combinatorial Theory (A), 17:1–11, 1974. [6] P. Matet. Some filters of partitions. The Journal of Symbolic Logic, 53:540– 553, 1988. [7] A.R.D. Mathias. Happy families. Annals of Mathematical logic, 12:59– 111, 1977. [8] F.P. Ramsey. On a problem of formal logic. London Mathematical Society, 30:264–286, 1930. [9] S. Shelah and O. Spinas. The distributivity numbers of finite products of P(ω)/fin. Fundamenta Mathematicae, 158:81–93, 1998. / Aquesta tesi és una contribució a la teoria combinatria de conjunts, específcament a la teoria de Ramsey, que estudia les particions de conjunts infinits. El principi combinatori bàsic diu que per a tota partició del conjunt dels nombres naturals en un nombre finit de classes hi ha un conjunt infinit de nombres naturals que està inclòs en una de les classes. El teorema de Ramsey [6], que hom pot veure com una generalització d'aquest principi bàsic, tracta de les particions del conjunt [N]k de tots els subconjunts de k elements de nombres naturals. Afirma que, per a cada k >/=1 i cada partició de [N]k en un nombre finit de classes, existeix un subconjunt infinit de nombres naturals, M, tal que tots els subconjunts de k elements de M pertanyen a una mateixa classe. Els conjunts amb aquesta propietat són homogenis per a la partició. En [3], Neil Hindman va demostrar un resultat de tipus Ramsey que Graham i Rotschild havien conjecturat en [2]. El teorema de Hindman afirma que si el conjunt de nombres naturals es divideix en dues classes, almenys una d'aquestes classes conté un conjunt infinit tal que totes les sumes finites d'elements distints del conjunt pertanyen a la mateixa classe. La demostració original del Teorema de Hindman va ser simplificada per James Baumgartner en [1]. En aquesta tesi donem noves demostracions d'aquests dos teoremes, basades en la tècnica del forcing. Després, analitzem els ordres parcials corresponents i n'estudiem les propietats i la relació amb altres ordres coneguts semblants. L'ordre parcial emprat en la demostració del teorema de Ramsey és equivalent al forcing de Mathias, definit en [5]. L'ordre parcial que apareix en la prova del teorema de Hindman, que anomenem PFIN, serà l'objecte d'estudi principal de la tesi. En el primer capítol donem algunes definicions bàsiques i enunciem alguns teoremes coneguts que necessitarem més endavant. El segon capítol conté la demostració del teorema de Ramsey. Usant la tècnica del forcing, produïm un conjunt homogeni per a una partició donada. L'ordre parcial que utilitzem és equivalent al de Mathias. En el tercer capítol, modifiquem la demostració de Baumgartner del teorema de Hindman per definir un ordre parcial, que anomenem PC , a partir del qual, mitjançant arguments de forcing, obtenim el conjunt homogeni buscat. Aquí, C es un conjunt infinit de conjunts finits disjunts de nombres naturals, i PC afegeix una successió de conjunts finits de nombres naturals amb la propietat de que totes les unions finites de elements d'aquesta successió pertanyen al conjunt C . A partir d'aquesta successió és fàcil obtenir un conjunt homogeni per a la partició del teorema original de Hindman. L'ordre parcial PC és similar a l'ordre definit per Pierre Matet en [4] i també al forcing de Mathias. Per això, és natural preguntar-nos si aquests ordres són equivalents o no. En el quart capítol treballem amb un ordre parcial que és equivalent a PC i que anomenem PFIN. Mostrem que PFIN té les propietats següents: (1) A partir d'un filtre genèric per a PFIN obtenim una successió infinita de conjunts finits de nombres naturals. Com en el cas del real de Mathias, aquesta successi_o ens permet reconstruir tot el filtre genèric. (2) PFIN afegeix un real de Mathias, que és un "dominating real". Ara bé, si afegim un "dominating real" afegim també un "splitting real". Aquest fet ens permet concloure que PFIN no és equivalent al forcing de Matet, ja que el forcing de Matet no afegeix "splitting reals" (3) PFIN es pot veure com una iteració de dos ordres parcials, el primer dels quals és "sigma-closed" i el segon és "sigma-centered". (4) PFIN té la "pure decision property". (5) PFIN no afegeix reals de Cohen. En el cinquè capítol demostrem que PFIN afegeix un real de Matet i, finalment, que el forcing de Mathias no afegeix reals de Matet. Això és com demostrem que el forcing de Mathias i PFIN no són ordres equivalents. Al final del capítol donem una aplicació de PFIN. Demostrem que un cert ordre definit per Saharon Shelah en [7], que anomenem M2, és una projecció de PFIN. Això implica que si G és un filtre PFIN-genèric sobre V, l'extensió V [G] conté també un filtre genèric per a M2. L'ordre M2 és una mena de producte de dues cópies del forcing de Mathias. REFERÈNCIES [1] J.E. Baumgartner. A short proof of Hindman's theorem, Journal of Combinatorial Theory, 17: 384-386, (1974). [2] R.L. Graham and B.L. Rothschild. Ramsey's theorem for m-parameter sets, Transaction American Mathematical Society, 159: 257-292, (1971). [3] N. Hindman. Finite sums from sequences within cells of partitions of N, Journal of Combinatorial Theory (A), 17: 1-11, (1974). [4] P. Matet. Some _lters of partitions, The Journal of Symbolic Logic, 53: 540-553, (1988). [5] A.R.D. Mathias. Happy families, Annals of Mathematical Logic, 12: 59-111, (1977). [6] F.P. Ramsey. On a problem of formal logic, London Mathematical Society, 30:264_D286, 1930. [7] S. Shelah and O. Spinas. The distributivity numbers of finite products of P(!)=fin, Fundamenta Mathematicae, 158:81_D93, 1998.

This thesis focuses on the semantics of definite descriptions (DDs). In chapter 1 I introduce a framework for doing compositional semantics for natural language that follows Heim and Kratzer (1998) and Fintel and Heim (2011). I also address a number of issues concerning the methodology of natural language semantics, as well as the theoretical desiderata that we aim to achieve. In chapter 2 I offer a reconstruction within this theoretical framework of three classical theories of DDs: the Russellian theory, the Fregean theory, and the Barwise and Cooper (1981) theory. Chapter 3 focuses on incomplete DDs. The incompleteness problem affects not only the Russellian theory, but also the Fregean and B&C theories. I argue that the syntactic variable approach to QDR proposed by Stanley and Szabó (2000a) offers a solution to the incompleteness problem that is equally applicable to the three theories of DDs introduced. Chapter 4 focuses on the referential/attributive distinction. Although intuitions of singularity are not part of our methodology, I point out (following Neale (2004)) that there are independent reasons why the Russellian theory predicts that a DD is semantically a rigid designator when it is used referentially. I argue that this proposal is applicable not only to the Russellian theory, as Neale does, but also to the Fregean and the B&C theories. In Chapter 5 and 6 I look at non-denoting DDs (i.e. DDs for which either uniqueness or existence fails to be satisfied). In chapter 5 I address the phenomenon called ‘presupposition’ in the literature, distinguishing between various kinds of data that are usually treated under this heading. I argue that with respect to a certain characterization of presuppositions, the Fregean theory and the B&C theory have more explanatory power than the Russellian theory. Chapter 6 deals with the truth-value intuitions triggered by utterances of sentences containing improper DDs. With respect to failures of uniqueness, I discuss Ramachandran’s (1993) argument and offer an improved version of it, which provides a compelling objection against the Russellian theory. With respect to failures of existence, I argue that the Fregean and the B&C theorist are in a better position to account for the patter of data than the Russellian. In chapter 7 I address data concerning the embedding of DDs in propositional attitude verbs. I discuss in detail the objection proposed by Heim (1991) against the Russellian theory. Again, this poses an important problem to the Russellian theory, while the Fregean and the B&C theories are not affected by the objection. The overall conclusion that this discussion leads to is that the Russellian theory is in general less prepared to account for the kinds of truth-conditional data we have considered than the alternative proposals discussed. The conclusions of chapters 6 and 7, and partially those of chapter 5, all indicate that the Russellian theory is the worst of the three options considered. The main positive contribution of this thesis is to point out that the B&C theory, although generally ignored in the literature, has the same theoretical virtues as the Fregean theory with respect to accounting for the range of data considered. / Esta tesis se centra en la semántica de las descripciones definidas (DDs). En el capítulo 1 introduzco un marco teórico para la semántica composicional del lenguaje natural que sigue la propuesta de Heim y Kratzer (1998) y Fintel y Heim (2011). En el capítulo 2 ofrezco una reconstrucción dentro de este marco de tres teorías clásicas de las DDs: la teoría de Russell, la teoría de Frege, y la propuesta de Barwise y Cooper (1981). El capítulo 3 tiene como enfoque las DDs incompletas y el capítulo 4 se centra en la distinción entre los usos referenciales y los usos atributivos. Argumento que ninguno de estos fenómenos nos permite elegir entre las tres teorías de las DDs introducidas. En los capítulos 5 y 6 analizo las DDs que no denotan. En el capítulo 5 sostengo que, con respecto a una determinada caracterización de las presuposiciones, la teoría de Frege y la de B&C tienen más poder explicativo que la teoría russelliana. El capítulo 6 trata de las intuiciones acerca de los valores de verdad de las oraciones que contienen DDs que no denotan. Discuto la objeción de Ramachandran (1993) a la teoría russelliana y ofrezco una versión mejorada de esta objeción. En el capítulo 7 analizo los datos provenientes de la inserción de DDs en el complemento de los verbos de actitud proposicional. Discuto la objeción propuesta por Heim (1991) contra la teoría russelliana. Una vez más, se trata de un problema importante para esta teoría que no afecta a las teorías de Frege y de B&C. La conclusión general de esta discusión es que la teoría de Russell es la menos preparada de las tres propuestas consideradas para dar cuenta de los tipos de datos lingüísticos analizados. Esta conclusión se sostiene sobre los resultados de los capítulos 6 y 7, y parcialmente los del capítulo 5. La principal contribución positiva de este trabajo es la de señalar que la teoría de B&C, aunque generalmente ignorada en la literatura relevante, tiene las mismas virtudes teóricas que la teoría de Frege con respecto a los datos que se han considerado aquí.