The concept of faster-than-light (FTL) motion challenges our fun- damental understanding of causality and relativity. This paper ex- plores a phenomenological model for velocity computation, examining the dependence of normalized velocity v/c on parameters such as the effective coupling Γx, the angle β, and terms incorporating lα and Θr. Multiple parameter configurations are investigated through numerical simulation to identify cases where velocities approach or exceed c, the speed of light. Key trends and observations are highlighted, providing a framework for future (...) theoretical work. (shrink)

We recall, "a priori," numeric energy expression: -/- Energy Numbers -/- $\begin{gathered}\mathcal{V}=\left\{f \mid \exists\left\{e_1, e_2, \ldots, e_n\right\} \in E \cup R\right\} \\ \mathcal{V}=\left\{f \mid \exists\left\{e_1, e_2, \ldots, e_n\right\} \in E, \text { and }: E \mapsto r \in R\right\} \\ \mathcal{V}=\left\{E \mid \exists\left\{a_1, \ldots, a_n\right\} \in E, E \not \neg r \in R\right\}\end{gathered}$ -/- We now introduce the set of optimized energy numbers: -/- ($H_a \in \mathcal{H}$ or $P^n = NP$ or $(P,\mathcal{L},F) = NP$). -/- Based on our formulation of (...) the bi-objective optimization task, we can make the following mathematical inferences: -/- 1. If the optimized energy numbers set $\mathcal{N}_H$ is equal to the original energy numbers set $\mathcal{E}$, i.e. $\mathcal{N}_H = \mathcal{E}$, then the maximum optimization score is achieved, i.e. the bi-objective optimization task is solved. This implies that there exists at least one solution to the optimization problem and $H_a \in \mathcal{H}$, where $H_a$ is the hypothesis that states the existence of an efficient algorithm to solve the problem. -/- 2. If the optimized energy numbers set $\mathcal{N}_H$ is a subset of the original energy numbers set $\mathcal{E}$, i.e. $\mathcal{N}_H \subset \mathcal{E}$, then the optimization score is less than the maximum score. This indicates that there may exist more efficient algorithms to solve the problem, and the hypothesis $H_a$ is still possible. -/- 3. If the optimized energy numbers set $\mathcal{N}_H$ is a superset of the original energy numbers set $\mathcal{E}$, i.e. $\mathcal{N}_H \supset \mathcal{E}$, then the optimization score is higher than the maximum score. This implies that the optimization problem may be easier than initially thought, and $P^n = NP$, or at least some form of $NP$-completeness. -/- 4. If the optimized energy numbers set $\mathcal{N}_H$ is a strict subset of the original energy numbers set $\mathcal{E}$, i.e. $\mathcal{N}_H \subsetneq \mathcal{E}$, and $P^n \neq NP$, then it can be concluded that the optimization problem is complex but there may exist algorithms that can efficiently approximate the solution. -/- 5. If the optimized energy numbers set $\mathcal{N}_H$ is empty, i.e. $\mathcal{N}_H = \emptyset$, then it can be inferred that the optimization problem is infeasible, i.e. no efficient algorithm exists to solve it, and $H_a$ is false. -/- 6. Comparing the two objectives in the bi-objective optimization task, we can make the following statements: -/- - The first objective, $\frac{\delta_{v(f)}(\mathbf{v}, \mathbf{w_{max}})} {\langle \mathbf{v_f}, \mathbf{1_f}\rangle}$, measures the efficiency of the algorithm and its ability to find low energy numbers. - The second objective, $\rho(\mathcal{N}_H)$, measures the accuracy of the algorithm in terms of loss and perplexity on the HyperLanguageModel. - Therefore, by optimizing both objectives simultaneously, we aim to find an efficient algorithm that also minimizes the loss and perplexities on the HyperLanguageModel. - If the optimization task is successfully solved, then the algorithm achieves both high efficiency and high accuracy. This would imply that the algorithm is able to find low energy numbers effectively and also generalize well on the HyperLanguageModel. -/- The optimized energy numbers aim to find a set of numbers $\mathbf{v}$ that maximize the bi-objective optimization task, while also minimizing the loss and perplexity of the HyperLanguageModel. This is achieved by finding the set of numbers that have the highest delta value and the lowest perplexity, resulting in a more optimized and efficient set of energy numbers. -/- By comparing the optimized energy numbers to the original set, we can see that the optimized set may have a higher delta value and a lower perplexity, indicating that it is a better set of numbers for the given task. This shows that the optimized energy numbers have successfully achieved their goal of maximizing efficiency while minimizing loss and perplexity. (shrink)

Higher - dimensional calculus and integral transformation play crucial roles in advancing our understanding of complex systems in mathematics and theoretical physics . Integral transformations are instrumental in simplifying complex differential equations, enabling the resolution of multi - dimensional problems that arise in various scientific fields . This paper aims to delve into a specific higher - dimensional integral transformation defined by the axioms \(F[q, s, l, \alpha]\) and \(G[q, s, l, \beta, c]\) . We start by outlining the axioms (...) which define the functions \(F\) and \(G\) . Specifically, Axiom 1 defines \(F\) as a function of four variables : \(q\), \(s\), \(l\), and \( \alpha\), whereas Axiom 2 defines \(G\) as a function that additionally includes variables \( \beta\) and \(c\) . Axiom 3 relates \(h\) and \(l\) via a sine function . The core of our investigation is the integral transformation expressed as a five - dimensional integral involving \(G\) and proving its equivalence to \(F\), provided a specific condition on \(c\) holds . We approach this problem by first deriving the expression for \(c\) through detailed differentiation of \(F\) and equating it to \(G\) . The derivation involves advanced calculus techniques and symbolic mathematics to solve the resulting equations . We then verify the derived expression for \(c\) by substituting it back into the relationship between \(F\) and \(G\), ensuring that the equality holds under integral transformation . Finally, to corroborate our findings, we employ visualizations through multidimensional contour plots to illustrate the relationship between the derived expressions . This provides an intuitive confirmation of the mathematical consistency and validity of the transformation . This paper contributes to the field by providing a nuanced and detailed examination of higher - dimensional integral transformations and their underlying mathematical structures . The results have potential implications for theoretical physics, particularly in areas involving complex systems and multi - dimensional analyses . (shrink)

DESENVOLVIMENTO EMBRIONÁRIO E DIFERENCIAÇÃO SEXUAL -/- E. I. C. da Silva Departamento de Agropecuária – IFPE Campus Belo Jardim Departamento de Zootecnia – UFRPE sede -/- 1.1 INTRODUÇÃO O sexo foi definido como a soma das diferenças morfológicas, fisiológicas e psicológicas que distinguem o macho da fêmea permitindo a reprodução sexual e assegurando a continuidade das espécies. Os processos de diferenciação sexual são realizados durante o desenvolvimento embrionário, onde ocorre a proliferação, diferenciação e maturação das células germinativas e primordiais, precursoras (...) de ovócitos e espermatozoides em fêmeas e machos, respectivamente. Assim, os embriões machos e fêmeas iniciam o seu desenvolvimento de forma semelhante, de modo que em ambos os sexos se estabelecem em estruturas idênticas a partir das quais se formarão os órgãos reprodutores correspondentes a cada sexo. O conhecimento da origem e do desenvolvimento do aparelho genital é indispensável para entender sua função e as alterações que produzem infertilidade ou esterilidade. 1.2 DETERMINAÇÃO DO SEXO CROMOSSÔMICO Nos mamíferos, o sexo cromossômico é determinado no momento da fertilização, quando um óvulo, que contém um cromossomo X, é fecundado por um espermatozoide portador de um cromossomo X ou um cromossomo Y. No primeiro caso, o complemento cromossômico seria XX, o que originaria uma fêmea (sexo homogamético), e no segundo daria como resultado um macho com a fórmula cromossômica XY (sexo heterogâmico). 1.3 A GÔNADA INDIFERENCIADA A primeira manifestação das gônadas se aprecia no embrião em forma de um par de eminências longitudinais chamadas cristas ou dobras gonodais, situadas em ambos os lados da linha média entre os mesonefros (rins em desenvolvimento) e do mesentério dorsal. Nos embriões dos mamíferos, as células germinativas primordiais (CGP) manifestam-se em estágios precoces do desenvolvimento, podendo ser detectadas pela primeira vez na metade da gastrulação. As CGP são células grandes, de citoplasma claro e núcleo grande e redondo, localizadas na parede do saco vitelino, perto do alantoide. Essas células possuem grande capacidade de proliferação e vão migrar desde o endoderma do intestino e o epitélio do saco vitelino, através do mesentério, até as cristas gonodais. Isso ocorre por volta do 26° dia da gestação no bovino. Sua migração realiza-se graças aos movimentos de translocação passiva e deslocamento ameboide ativo. Desconhece-se o mecanismo pelo qual estas células são dirigidas para as cristas gonodais, porém foram estudadas algumas moléculas que se expressam durante sua migração e que poderiam desempenhar um papel importante na diferenciação deste tipo celular. A fosfatase alcalina é uma enzima que tem sido usada como marcador de CGP para determinar a sua origem e migração. Num estudo recente, foi inserido um marcador fluorescente que se exprime unicamente nas células germinativas primordiais de embriões transgênicos, e utilizando este marcador e a fosfatase alcalina determinou-se a origem e o padrão de migração destas células. O primeiro sinal de diferenciação das células germinativas primordiais é a expressão de fosfatase alcalina, e esta apareceu pela primeira vez na parte mais posterior da linha primitiva. No sétimo dia de desenvolvimento no embrião do camundongo, o endoderma visceral (AF+) é substituído pelo endoderma definitivo (AF-) originado na parte anterior da linha primitiva. O fator de transcrição Oct-4 é expresso nas CGP de ambos os sexos, pelo que acredita-se estar envolvido na mantença a totipotêncialidade das células. O receptor tirosina quinase, cujo ligante é o fator de Steel, é outra das moléculas que expressam as CGP. Tem sido demonstrado que este receptor possui um papel muito importante na sobrevivência deste tipo celular. Existem outros fatores que promovem a sobrevivência e/ou proliferação de CGP in vitro. Em experiências realizadas com o fator de transformação beta I (TGFβ-I), observou-se que este tem um efeito negativo sobre a proliferação das CGP. Outra atividade que tem sido postulada a este fator é o de um agente quimioatraente que possivelmente possa direcionar a migração destas células para a gônada. a) Um formado pelas células germinativas primordiais (precursoras dos gametas masculinos ou femininos), rodeadas de células somáticas das quais posteriormente se derivarão as células de Sertoli no macho e as células da granulosa na fêmea. b) O tecido que formará o estroma da gônada: tecido conjuntivo, vasos sanguíneos e as células intersticiais com atividade esteroidogênica (células de Leydig no testículo e a teca interna do ovário). As células somáticas do primórdio gonodal originam-se do mesoderma. Inicialmente são de três tipos: mesenquimáticas, mesoteliais e endoteliais. As células mesenquimáticas e mesoteliais iniciam grande atividade proliferativa ao chegar as CGP. Observa-se então uma condensação de células de origem mesotelial e mesenquimatoso que forma um agregado compacto denominado "blastema gonodal". A partir deste primórdio embrionário, diferenciam-se dois tecidos gonodais: os cordões sexuais e o estroma. Os cordões sexuais são arranjos epiteliais que se encontram delimitados por uma folha basal, e dentro deles encontramos as CGP. Por sua vez, no estroma encontram-se células do tipo mesenquimático e vasos sanguíneos. Neste momento, as gônadas são indiferenciadas e bipotencialmente sexuais, sendo impossível diferenciar, morfologicamente, uma gônada masculina de uma feminina, mas no caso dos machos genéticos já existe uma diferenciação da gônada a nível molecular. Nesta fase já se encontram presentes as estruturas das quais se desenvolvem os dutos mesonéfricos ou de Wolff precursores do aparelho genital masculino e os dutos paramesonéfricos ou de Müller que darão origem ao aparelho reprodutor feminino. Há uma série de fatores envolvidos no desenvolvimento precoce da gônada, entre os quais o fator esteroidogênico I (SFI: Steroidogenic fator l), que é um membro da subfamília de receptores nucleares, receptores órfãos. Este fator de transcrição tem um local de ligação ao DNA composto por dois dedos-de-Zinc. O SFI foi identificado como um ativador de genes envolvidos na biossíntese de esteroides em diferentes células. O SFI está presente durante o desenvolvimento embrionário em regiões associadas com funções endócrinas como gônadas, adrenais, pituitárias e hipotálamos. Os animais homozigotos para o gene SFI defeituoso, necessitam de gônadas e adrenais e têm a função gonadotrófica alterada. Os ratos sem SFI carecem de gonadotrofos e têm um desenvolvimento anormal do núcleo ventro-medial do hipotálamo; em particular as gônadas deixam de se desenvolver entre os dias 11 a 15 e degeneram-se por apoptose. No entanto, a crista genital forma-se e é colonizada pelas células germinativas, o que indica que estas continuam a receber o sinal adequado para a sua migração. Portanto, o SFI não está envolvido no desenvolvimento precoce da gônada e do sistema urogenital, mas parece estar envolvido na manutenção do crescimento das células somáticas presentes na gônada indiferenciada. O gene associado ao tumor de Wilms (WTI: Wilm's tumor Associated) está envolvido no desenvolvimento da gônada e do rim. Durante o desenvolvimento embrionário, WTI se expressa em todo o mesoderma intermediário e posteriormente na gônada indiferenciada, bem como no rim em formação. WTI regula o sinal indutivo do mesênquima para o epitélio celômico dos mesonefros. Se este for o caso, então WTI é responsável pelo crescimento da crista genital ao dirigir a entrada do epitélio celômico. Dado que estas células darão origem às células de Sertoli, a carência de WTI pode causar o desenvolvimento de embriões XY como fêmeas simplesmente porque não se formam as células de Sertoli. Em geral, todos os genes importantes na diferenciação do mesoderma intermediário e do sistema urogenital intervêm no desenvolvimento da gônada precoce. 1.4 DIFERENCIAÇÃO GONODAL O desenvolvimento das gônadas e ductos genitais descritos até o momento, é o mesmo para ambos os sexos. Igualmente, os genes descritos, que estão envolvidos no desenvolvimento das gônadas, ductos genitais e migração das células germinativas, afetam igualmente os embriões com genótipo XX ou XY. A gônada primitiva consiste anatomicamente de uma medula (interna) e uma crosta (externa), e de acordo com o local onde ocorre a colonização das células germinativas, diferenciara em testículo ou um ovário, respectivamente. Nos mamíferos, a primeira manifestação estrutural de diferenciação sexual é detectada na gônada dos machos, onde as células germinativas estão localizadas na medula. A diferenciação do testículo inicia-se quando os cordões sexuais se separam do epitélio celômico como consequência dos arranjos produzidos por uma invasão do mesênquima e vasos sanguíneos que provoca a compactação dos cordões, agora denominados cordões testiculares. As células que rodeiam os cordões se achatam e formam as células mioides, que são responsáveis pela formação das membranas basais. As células do epitélio interno, ou seja, as células de Sertoli, têm duas funções principais: o suporte das CGP e a síntese da hormona antimulleriana, responsável pela regressão dos ductos de Müller e secretada durante o período de diferenciação sexual. As células do estroma que rodeiam os cordões testiculares diferenciam-se para formar vários tipos de células: células mioides, fibroblastos, endotélio e células de Leydig, que são as mais importantes pela sua atividade endócrina. Posteriormente, os cordões testiculares dão origem aos túbulos seminíferos, que contêm o epitélio que produzirá os espermatozoides ao chegar à puberdade. Na fêmea, durante os estágios iniciais de diferenciação gonodal, não se observam mudanças em relação à gônada indiferenciada, só pode-se observar um certo crescimento devido à proliferação de células somáticas e germinativas. As células germinativas iniciam um período de proliferação, que termina com o início da meiose. Iniciada a meiose, dá-se o processo de foliculogênese; neste momento os cordões epiteliais se fragmentam, de tal maneira que cada ovócito fica rodeado de células epiteliais cobertas por uma folha basal fina (figura 1). Para que a gônada primitiva se desenvolva em testículo é indispensável a presença do cromossoma Y, independentemente do número de cromossomas X que contenha o genoma de um indivíduo. O gene determinante do testículo encontra-se localizado no cromossoma Y, denominado sry em ratos e SRY em humanos. O gene sry se expressa durante o desenvolvimento embrionário na crista genital de embriões de camundongos. A expressão é detectável no dia 10,5, pouco depois do aparecimento das cristas genitais, atinge o seu máximo durante o dia 11,5 e mantém-se até pouco depois de ocorrerem os primeiros sinais morfológicos de diferenciação testicular no dia 12,5. Este padrão de expressão é compatível com a teoria de que sry atua induzindo a ativação dos genes (figura 2) que conduzem ao desenvolvimento testicular, sem que exista a necessidade da expressão contínua de sry para manter a diferenciação do testículo após o dia 12,5. Como mencionado anteriormente, a gônada primitiva é composta por vários tipos de células. No entanto, as células germinativas primordiais não são o local de expressão do sry, já que os embriões que necessitam de células germinativas mantêm a expressão de sry e desenvolvem o sexo gonodal normalmente. As células somáticas na gônada em desenvolvimento incluem também as células de suporte. Sabe-se que é nestas células que o sry é expresso para que se diferenciem em células de Sertoli, e a expressão transitória de sry indica que deve ativar a outros genes para a manutenção das células de Sertoli. Uma vez diferenciadas as células de Sertoli, elas se encarregarão da diferenciação do resto das células na gônada. -/- Figura 1: Representação da diferenciação dos órgãos genitais internos. Adaptado de BRONSON, 1989. Figura 2: Cascada de genes envolvidos na diferenciação sexual, adaptado de KOOPMAN, 1999. O fator sry é necessário para a diferenciação do testículo. Embora não se conheçam os genes que provavelmente regulam esse gene, estudos realizados em camundongos demonstram que este gene parece coordenar-se com certos genes autossômicos. Entre estes genes autossômicos, o sox9, que é produzido pelas células de Sertoli uma vez que são estimuladas por sry, de modo que sox9 é um dos genes relacionados estruturalmente com sry. O Sox9 funciona como um fator de transcrição, mas não se sabe se a proteína tem qualquer outra função estrutural; este gene exprime-se abundantemente nos condrócitos e está relacionado com defeitos do aparelho ósseo chamados displasia campomélica. Curiosamente, os pacientes XY com esta condição sofrem frequentemente de reversão do sexo. O Sox9 é um dos poucos genes, além do SRY, do qual as mutações demonstraram interferir com a determinação sexual masculina. No entanto, apenas 75% dos pacientes com anomalias esqueléticas de tipo displasia campomélica têm reversão sexual e não foram encontrados casos de reversão sexual devido a um defeito de Sox9 que não seja acompanhado de defeitos esqueléticos. Isso indica que o Sox9 é apenas um membro da rede de genes que são ativados para determinar a diferenciação sexual, enquanto a rota que rege a condrogênese é mais sensível a perturbações deste. O momento em que se detecta a expressão do gene Sox9 (11dpc em ratos) coincide com a máxima expressão de sry, o que poderia indicar a possibilidade de que sry regule positivamente a Sox9. De fato, na região do promotor de Sox9 há um local de união ao que potencialmente se pode unir o sry. A expressão de Sox9 durante a diferenciação sexual sugere um papel abaixo de sry na diferenciação das células de Sertoli. O cromossoma X também é importante na diferenciação gonodal. O gene DAX-I foi isolado do lócus DSS (Dosage sensitive sex reversal) do cromossoma X. DAX-I é parte da cascata de determinação sexual, mas não é necessário para a formação do testículo. DAX-I é um membro dos receptores nucleares conhecidos como receptores órfãos. Este gene demonstrou ser um poderoso repressor da transcrição de SFI e de vários genes. Os padrões de expressão de DAX-I são complementares daqueles de SFI, ambos expressos nas cristas genitais. Em resumo, dada a evidência exposta, desenvolveu-se a hipótese de que DAX-I é um antagonista de sry; esse antagonismo é dependente dos níveis relativos de DAX-I e sry e de um limiar que varia de espécie para espécie. A DAX-I foi classificada como o gene antitestículo. Na fêmea (cariótipo XX) é importante que ocorra a inativação de um dos cromossomas sexuais X para que se mantenha o equilíbrio genético ao igualar o conteúdo de DNA dos cromossomas. Esse cromossoma inativado constitui o chamado corpúsculo de Barr. No entanto, para que a meiose se realize, é necessário dos dois cromossomas X ativos nos ovócitos para assegurar a diferenciação ovárica e a fertilidade. 1.5 DIFERENCIAÇÃO DOS DUCTOS SEXUAIS O embrião possui, além das gônadas indiferenciadas, dois sistemas de ductos: os de potencialidade masculina denominam-se ductos de Wolff ou mesonéfricos, e os de potencialidade feminina se chamam ductos de Müller ou paramesonéfricos (figura 1). Se a diferenciação gonodal levou à formação de um testículo, a partir do ducto mesonéfrico ou de Wolff se desenvolverão os ductos eferentes, o epidídimo, os ductos deferentes e as vesículas seminais. As hormonas importantes no desenvolvimento do aparelho genital masculino são a testosterona, produzida pelas células de Leydig, e sua forma 5α reduzida, a 5α di-hidrotestosterona. Acredita-se que a testosterona é responsável pela virilização dos ductos de Wolff, e a di-hidrotestosterona dos órgãos genitais externos. No macho, os canais de Müller atrofiam-se devido à ação de uma hormona fetal de origem testicular denominada hormona inibidora das estruturas de Müller (HIM) ou hormona antimulleriana. Este processo começa assim que os cordões espermáticos se formam e se diferenciam as células de Sertoli. A existência de HIM foi proposta baseada em estudos realizados em bezerras freemartin, devido à existência de uma hormona responsável pela atresia dos ductos de Müller que na fêmea dá origem ao útero e aos ovidutos. Essa hormona provoca a involução do aparelho genital do bovino nas gestações gemelares nas quais os produtos de diferente sexo têm comunicação sanguínea por ter ocorrido a anastomose dos vasos de ambas as placentas (figura 3). A HIM é uma glicoproteína pertencente à subfamília de TGFβ, é expressa pelas células que darão origem às células de Sertoli e é um dos primeiros marcadores de diferenciação nestas células. A HIM é secretada na vida adulta pelas células de Sertoli no testículo e por células da granulosa no ovário. No rato a HIM é expressa-se no 12° dia em um teste padrão que segue muito de perto o aumento na expressão de sry. No macho, esta secreção de HIM continua durante a vida fetal e adulta, contudo os níveis de HIM declinam na puberdade devido a um aumento na secreção de testosterona. Vários fatores intervêm na regulação do gene de HIM, incluindo os acima descritos SFI e Sox9. O gene HIM contém segmentos de DNA que são conservados em várias espécies de vertebrados. Existe um nexo de ligação para SFI, que ativa a transcrição de HIM. A mutação no local de ligação de SFI resulta em reversão do sexo em indivíduos XY incluindo genitais femininos normais, presença de um útero formado enfatizando a importância de SFI na determinação sexual e na expressão de HIM. Embora SFI seja um bom candidato como regulador de HIM, é expresso em outras células, como as de Leydig e adrenais, que não expressam HIM. Em contrapartida, Sox9 é expresso unicamente nas células de Sertoli que são as produtoras de HIM. O gene HIM também tem um nexo de ligação para Sox9. Além disso, Sox9 pode atuar sinergicamente com SFI para promover a secreção de HIM. Ao contrário destes dois fatores de transcrição, DAX-I antagoniza a ação de Sox9 e provavelmente SFI sobre o promotor de HIM. Assim, para que as células de Sertoli secretem HIM, a transcrição de DAX-I deve diminuir. Figura 3: Representação da diferenciação dos órgãos genitais externos. Adaptado de BRONSON, 1989. Os ductos de Wolff tornam-se o sistema de ejaculação do macho. A porção mais próxima dos testículos dá origem ao epidídimo, a parte central ao ducto deferente e a porção mais distal às vesículas seminais. A próstata e a parte membranosa da uretra do macho desenvolvem-se a partir da porção pélvica do seio urogenital. A virilização e diferenciação dos ductos de Wolff dependem da produção de testosterona pelo testículo. Quanto aos órgãos genitais externos do macho, o tubérculo genital é ampliado e as dobras uretrais se fundem para formar a uretra peniana. A fusão das dobras uretrais aproxima os tubérculos genitais para formar o escroto (figura 4). Figura 4: Diferenciação do aparelho genital da fêmea e do macho. Adaptado de KOOPMAN, 1989. A diferenciação dos órgãos genitais da fêmea ocorre de forma passiva, já que a ausência de testículos e por isso da hormona inibidora dos ductos de Müller (HIM), assim como dos andrógenos virilizantes, favorece o desenvolvimento dos ductos de Müller, enquanto os de Wolff sofrem atrofia. A porção cefálica dos ductos de Müller dá origem aos ovidutos, que na sua terminação caudal se fundem com o útero. O contato dos ductos de Müller com o seio urogenital induz uma intensa proliferação celular que resulta na formação da área uterovaginal localizado entre o seio urogenital e os ductos de Müller. As células do prato uterovaginal proliferam e aumentam a distância entre as duas estruturas criando o espaço que formará a vagina quando o prato é canalizado e forma um lúmen. Em contraste com o que ocorre no macho, na fêmea a maior parte do seio urogenital se mantém exposta na superfície da abertura onde desembocam a vagina e a uretra. O tubérculo urogenital da fêmea tem um crescimento limitado e forma o clitóris. A sequência de passos da diferenciação sexual do aparelho genital é resumida na tabela 1. Tabela 1: Destino em desenvolvimento dos rudimentos sexuais dos fetos macho e fêmea dos mamíferos -/- Rudimento sexual Macho Fêmea Gônada Testículo Ovário Ductos de Müller (Paramesonéfricos) Vestígios Útero, parte da vagina, ovidutos Ductos de Wolff (Mesonéfricos) Ductos eferentes deferentes, epidídimo, vesículas seminais Vestígios Seio urogenital Uretra, próstata, glândulas bulbouretrais Parte da vagina, uretra, vestíbulo, glândulas vestibulares Tubérculo genital Pênis Clitóris Pregas vestibulares Escroto Lábios vulvares Fonte: HAFEZ, 2004. 1.6 DIFERENCIAÇÃO SEXUAL DO HIPOTÁLAMO Os processos de diferenciação sexual não se limitam apenas às células somáticas do organismo do feto, mas incluem também os centros nervosos superiores do cérebro. Assim, da mesma maneira que a gônada e os ductos sexuais se desenvolvem para o tipo feminino ou masculino, propôs-se que o cérebro pode ser "masculinizado" ou permanecer "Feminizado". A diferenciação do hipotálamo vai depender do ambiente esteroidal do neonato e ocorre na fase perinatal. Estes eventos serão de grande transcendência na vida reprodutiva do indivíduo. Tanto a fêmea como o macho nascem com a capacidade de secreção de gonadotropinas de acordo com um padrão cíclico; contudo, no macho, a exposição do hipotálamo à ação dos andrógenos testiculares durante os primeiros dias da vida extrauterina provoca a masculinização, com o qual o hipotálamo do macho é programado para que a secreção de gonadotropinas se realize a um ritmo relativamente constante por parte da hipófise (secreção tônica). Na fêmea, tanto a secreção tônica como a cíclica se conservam. No entanto, observou-se que a injeção de testosterona ou o transplante de testículo na rata fêmea durante os primeiros dias de vida, suprime a sua futura atividade estral (secreção cíclica). Por outro lado, se os ovários forem transplantados para o rato macho normal castrado na idade adulta, o animal não desenvolve qualquer atividade cíclica, mas se os machos transplantados forem castrados ao nascer, o ovário é capaz de efetuar mudanças cíclicas e ovulações. Isto foi demonstrado em roedores, mas não em animais domésticos ou na espécie humana. Portanto, o padrão de secreção de gonadotropinas, seja cíclico ou tônico, não depende da hipófise, mas do hipotálamo e sua correta diferenciação. 1.7 CONCLUSÕES A maioria dos conhecimentos no campo da biologia do desenvolvimento e, muito especificamente, dos processos de diferenciação sexual têm sido originados de estudos relacionados com desordens congênitas, que na sua maioria devem-se a defeitos de genes específicos. A análise detalhada destas desordens permitiu entender alguns mecanismos endócrinos, moleculares e genéticos envolvidos na diferenciação sexual. A identificação do gene sry como determinante do testículo foi uma contribuição crucial e abriu as portas à compreensão dos mecanismos moleculares e celulares relacionados com o desenvolvimento do testículo. Se este gene não estiver presente, é criado um programa genético alternativo para levar a cabo a diferenciação gonodal para o ovário. Finalmente, devemos ter presente que é necessária uma correlação entre mudanças morfológicas e expressão de genes durante o desenvolvimento para entender os mecanismos relacionados com a diferenciação. -/- Apoio -/- Realização -/- REFERÊNCIAS BIBLIOGRÁFICAS ANDERSON, Robert et al. The onset of germ cell migration in the mouse embryo. Mechanisms of development, v. 91, n. 1-2, p. 61-68, 2000. AUSTIN, Colin Russell; SHORT, R. V. Reproduction in Mammals: Volume 1, Germ Cells and Fertilization. Londres: Cambridge University Press, 1972. BRONSON, Franklin H. Mammalian reproductive biology. Chicago: University of Chicago Press, 1989. BUEHR, Mia. The primordial germ cells of mammals: some current perspectives. Experimental cell research, v. 232, n. 2, p. 194-207, 1997. BYSKOV, Anne G. Differentiation of mammalian embryonic gonad. Physiological reviews, v. 66, n. 1, p. 71-117, 1986. CAPEL, Blanche et al. Migration of mesonephric cells into the mammalian gonad depends on Sry. Mechanisms of development, v. 84, n. 1-2, p. 127-131, 1999. CAPEL, Blanche. The battle of the sexes. Mechanisms of development, v. 92, n. 1, p. 89-103, 2000. DERIVAUX, Jules; BARNABÉ, Renato Campanarut. Reprodução dos animais domésticos. Zaragoza: Acribia, 1980. DOMENICE, Sorahia et al. Aspectos moleculares da determinação e diferenciação sexual. Arquivos Brasileiros de Endocrinologia & Metabologia, v. 46, n. 4, p. 433-443, 2002. DONAHOE, Patricia K. et al. Mullerian inhibiting substance activity in bovine fetal, newborn and prepubertal testes. Biology of reproduction, v. 16, n. 2, p. 238-243, 1977. HAFEZ, Elsayed Saad Eldin; HAFEZ, B. Reprodução animal. São Paulo: Manole, 2004. HANLEY, Neil A. et al. Steroidogenic factor 1 (SF-1) is essential for ovarian development and function. Molecular and cellular endocrinology, v. 163, n. 1-2, p. 27-32, 2000. HIORT, Olaf; PAUL-MARTIN, H. The molecular basis of male sexual differentiation. European journal of endocrinology, v. 142, n. 2, p. 101-110, 2000. HOLY, Lubos; MARTÍNEZ JÚSTIZ, G. Colab. Biología de la reproducción bovina. Havana: Revolucionária, 1975. JOSSO, Nathalie et al. The role of anti-Müllerian hormone in gonadal development. Molecular and cellular endocrinology, v. 145, n. 1-2, p. 3-7, 1998. JOST, Alfred et al. Studies on sex differentiation in mammals. In: Proceedings of the 1972 Laurentian Hormone Conference. Londres: Academic Press, 1973. p. 1-41. KNOBIL, Ernst. Knobil and Neill's physiology of reproduction. EUA: Gulf Professional Publishing, 2006. KOFMAN ALFARO, S.; MERCHANT LARIOS, H.; PEREZ PALACIOS, G. Diferenciacion sexual. I. Bases biologicas del dimorfismo sexual. Rev. invest. clín, p. 349-59, 1982. KOOPMAN, Peter. Sry and Sox9: mammalian testis-determining genes. Cellular and Molecular Life Sciences CMLS, v. 55, n. 6-7, p. 839-856, 1999. MCDONALD, L. E. Veterinary endocrinology. Lea & Febiger, Philadelphia, Pa, 1969. MEIZEL, S.; JOHNSON, M. H. Development in mammals. MH Johnson, Ed, v. 3, p. 1-64, 1978. MELLO, Maricilda Palandi de; ASSUMPÇÃO, Juliana de G.; HACKEL, Christine. Genes envolvidos na determinação e diferenciação do sexo. Arquivos Brasileiros de Endocrinologia & Metabologia, v. 49, n. 1, p. 14-25, 2005. -/- REFERÊNCIAS BIBLIOGRÁFICAS MERCHANT-LARIOS, H. Ovarian differentiation. The Vertebrate Ovary, p. 47-81, 1978. MIES FILHO, Antonio. Reprodução dos animais. Porto Alegre: Sulina, 1987. NEF, Serge; PARADA, Luis F. Hormones in male sexual development. Genes & Development, v. 14, n. 24, p. 3075-3086, 2000. PARKER, Keith L.; SCHEDL, Andreas; SCHIMMER, Bernard P. Gene interactions in gonadal development. Annual review of physiology, v. 61, n. 1, p. 417-433, 1999. SWAIN, Amanda; LOVELL-BADGE, Robin. Mammalian sex determination: a molecular drama. Genes & development, v. 13, n. 7, p. 755-767, 1999. WILHELM, Dagmar; PALMER, Stephen; KOOPMAN, Peter. Sex determination and gonadal development in mammals. Physiological reviews, v. 87, n. 1, p. 1-28, 2007. WILSON, Jean D.; GRIFFIN, James E.; GEORGE, Fredrick W. Sexual differentiation: early hormone synthesis and action. Biology of reproduction, v. 22, n. 1, p. 9-17, 1980. -/- Emanuel Isaque Cordeiro da Silva Belo Jardim, 07 de Maio de 2020. (shrink)

The practice of medicine frequently involves the unconsented restriction of liberty. The reasons for unilateral liberty restrictions are typically that being confined, strapped down, or sedated are necessary to prevent the person from harming themselves or others. In this paper, we target the ethics of chemical restraints, which are medications that are used to intentionally restrict the mental states associated with the unwanted behaviors, and are typically not specifically indicated for the condition for which the patient is being treated. Specifically, (...) we aim to identify the conditions under which chemical restraints are ethically permissible. It is wrong to assume that what is morally true of physical restraints is also true of chemical restraints. Our aim is thus to identify the conditions under which chemical restraints are permissible while distinguishing these conditions from those of the application of physical restraints. (shrink)

Increasingly complex and autonomous systems require machine ethics to maximize the benefits and minimize the risks to society arising from the new technology. It is challenging to decide which type of ethical theory to employ and how to implement it effectively. This survey provides a threefold contribution. First, it introduces a trimorphic taxonomy to analyze machine ethics implementations with respect to their object (ethical theories), as well as their nontechnical and technical aspects. Second, an exhaustive selection and description of relevant (...) works is presented. Third, applying the new taxonomy to the selected works, dominant research patterns, and lessons for the field are identified, and future directions for research are suggested. (shrink)

While artificial intelligence (AI) is increasingly applied for decision-making processes, ethical decisions pose challenges for AI applications. Given that humans cannot always agree on the right thing to do, how would ethical decision-making by AI systems be perceived and how would responsibility be ascribed in human-AI collaboration? In this study, we investigate how the expert type (human vs. AI) and level of expert autonomy (adviser vs. decider) influence trust, perceived responsibility, and reliance. We find that participants consider humans to be (...) more morally trustworthy but less capable than their AI equivalent. This shows in participants’ reliance on AI: AI recommendations and decisions are accepted more often than the human expert’s. However, AI team experts are perceived to be less responsible than humans, while programmers and sellers of AI systems are deemed partially responsible instead. (shrink)

I argue that in the Phaedo, Plato maintains that the soul is located in space and is capable of locomotion and of interacting with the body through contact. Numerous interpreters have dismissed these claims as merely metaphorical, since they assume that as an incorporeal substance, the soul cannot possess spatial attributes. But careful examination of how Plato conceives of the body throughout his corpus reveals that he does not distinguish it from the soul in terms of spatiality. Furthermore, assigning spatial (...) attributes to the soul plays an important role in Plato’s account of the relation of body and soul. (shrink)

Recent work has defended “Euclidean” theories of set size, in which Cantor’s Principle (two sets have equally many elements if and only if there is a one-to-one correspondence between them) is abandoned in favor of the Part-Whole Principle (if A is a proper subset of B then A is smaller than B). It has also been suggested that Gödel’s argument for the unique correctness of Cantor’s Principle is inadequate. Here we see from simple examples, not that Euclidean theories of set (...) size are wrong, but that they must be either very weak and narrow or largely arbitrary and misleading. (shrink)

There is no uniquely standard concept of an effectively decidable set of real numbers or real n-tuples. Here we consider three notions: decidability up to measure zero [M.W. Parker, Undecidability in Rn: Riddled basins, the KAM tori, and the stability of the solar system, Phil. Sci. 70(2) (2003) 359–382], which we abbreviate d.m.z.; recursive approximability [or r.a.; K.-I. Ko, Complexity Theory of Real Functions, Birkhäuser, Boston, 1991]; and decidability ignoring boundaries [d.i.b.; W.C. Myrvold, The decision problem for entanglement, in: (...) R.S. Cohen et al. (Eds.), Potentiality, Entanglement, and Passion-at-a-Distance: Quantum Mechanical Studies fo Abner Shimony, Vol. 2, Kluwer Academic Publishers, Great Britain, 1997, pp. 177–190]. Unlike some others in the literature, these notions apply not only to certain nice sets, but to general sets in Rn and other appropriate spaces. We consider some motivations for these concepts and the logical relations between them. It has been argued that d.m.z. is especially appropriate for physical applications, and on Rn with the standard measure, it is strictly stronger than r.a. [M.W. Parker, Undecidability in Rn: Riddled basins, the KAM tori, and the stability of the solar system, Phil. Sci. 70(2) (2003) 359–382]. Here we show that this is the only implication that holds among our three decidabilities in that setting. Under arbitrary measures, even this implication fails. Yet for intervals of non-zero length, and more generally, convex sets of non-zero measure, the three concepts are equivalent. (shrink)

This analytical study explores the nature of scientific progress connected to current philosophical definitions and the role of institutional governance in promoting this progress. This paper examines how public and private initiatives intersect to create a wartime level of scientific progress during peacetime, as promoted in detail by Vannevar Bush, Director of the Office of Scientific Research and Development (OSRD) from 1941-47. This study suggests that the public benefit from the war footing approach to scientific progress should outweigh the losses (...) to the public good that accumulate due to wartime restrictions on scientific discourse during times of peace. The interaction and dependence of scientific progress on military development, public health and public needs in general, the tax code and the patent system form the foundation of Bush’s program for sustaining wartime levels of scientific progress during peacetime. This study references the COVID-19 period and the solutions that were applied to emergent public needs through scientific programs. Justice of the United States (U.S.) Supreme Court Neil Gorsuch noted in May 2023 that “…we may have experienced the greatest intrusions on civil liberties in the peacetime history of this country.” This study proposes that the dilution of scientific truth in public policy is the result of a collective institutional mindset among scientists. This mindset endorses public programs that provide society with a wartime risk response in peacetime. In this study, from an epistemological standpoint and considering the work of other researchers in this field, these developments in scientific progress will be analyzed. (shrink)

Some theorists argue that moral bioenhancement ought to be compulsory. I take this argument one step further, arguing that if moral bioenhancement ought to be compulsory, then its administration ought to be covert rather than overt. This is to say that it is morally preferable for compulsory moral bioenhancement to be administered without the recipients knowing that they are receiving the enhancement. My argument for this is that if moral bioenhancement ought to be compulsory, then its administration is a matter (...) of public health, and for this reason should be governed by public health ethics. I argue that the covert administration of a compulsory moral bioenhancement program better conforms to public health ethics than does an overt compulsory program. In particular, a covert compulsory program promotes values such as liberty, utility, equality, and autonomy better than an overt program does. Thus, a covert compulsory moral bioenhancement program is morally preferable to an overt moral bioenhancement program. (shrink)

Epistemic burdens – the nature and extent of our ignorance (that and how) with respect to various courses of action – serve to determine our incentive structures. Courses of action that seem to bear impossibly heavy epistemic burdens are typically not counted as options in an actor’s menu, while courses of action that seem to bear comparatively heavy epistemic burdens are systematically discounted in an actor’s menu relative to options that appear less epistemically burdensome. That ignorance serves to determine what (...) counts as an option means that epistemic considerations are logically prior to moral, prudential, and economic considerations: in order to have moral, prudential, or economic obligations, one must have options, and epistemic burdens serve to determine our options. One cannot have obligations without doing some epistemic work. We defend this claim on introspective grounds. We also consider how epistemic burdens distort surrogate decision-making. The unique epistemology of surrogate cases makes the priority of the epistemic readily apparent. We then argue that anyone who accepts a principle similar to ought implies can is committed to the logical priority of the epistemic. We also consider and reject several possible counterarguments. -/- . (shrink)

There is recent empirical evidence that personal identity is constituted by one’s moral traits. If true, this poses a problem for those who advocate for moral enhancement, or the manipulation of a person’s moral traits through pharmaceutical or other biological means. Specifically, if moral enhancement manipulates a person’s moral traits, and those moral traits constitute personal identity, then it is possible that moral enhancement could alter a person’s identity. I go a step further and argue that under the right conditions, (...) moral enhancement can constitute murder. I then argue that these conditions are not remote. (shrink)

In this paper, I offer a new interpretation of Aristophanes’ speech in Plato’s Symposium. Though Plato deliberately draws attention to the significance of Aristophanes’ speech in relation to Diotima’s (205d-206a, 211d), it has received relatively little philosophical attention. Critics who discuss it typically treat it as a comic fable, of little philosophical merit (e.g. Guthrie 1975, Rowe 1998), or uncover in it an appealing and even romantic treatment of love that emphasizes the significance of human individuals as love-objects to be (...) valued for their own sakes (e.g. Dover 1966, Nussbaum 1986). Against the first set of interpreters, I maintain that Aristophanes’ speech is of the utmost philosophical significance to the dialogue; in it, he sets forth a view of eros as a state of lack and a corresponding desire for completion, which is the starting-point for Diotima’s subsequent analysis. Against the second, I argue that Aristophanes’ speech contains a profoundly pessimistic account of eros. Far from being an appreciative response to the individuality of the beloved, eros, for Aristophanes, is an irrational urge, incapable of satisfaction. It is this irrationality that precludes Aristophanes’ lovers from achieving the partial satisfaction of erotic desire that is open to their Socratic counterparts through their relationship to the forms. (shrink)

In this chapter, I offer an overview of current scholarly debates on Plato's Lysis. I also argue for my own interpretation of the dialogue. In the Lysis, Socrates argues that all love is motivated by the desire for one’s own good. This conclusion has struck many interpreters as unattractive, so much so that some attempt to reinterpret the dialogue, such that it either does not offer an account of interpersonal love, or that it offers an account on which love is, (...) in fact, an other-regarding state. Others, notably Vlastos, criticize Socrates’ theory as implausibly and repellently egoistic. I maintain, against the first group, that Socrates is indeed offering an egoistic theory of love. I argue, against the second, that, while Socrates’ theory may be repellent, it possesses considerable explanatory power and avoids certain weaknesses which infect contemporary approaches to love. (shrink)

Contemporary scholarship is divided over whether Anselm maintains a version of Eudaemonism. The debate centers on the question of whether the will for justice only moderates the will for happiness or, instead, provides a distinct end for which to act. Because of two key passages, various scholars hold that Anselm maintained elements of medieval Eudaemonism. In this article, I argue that Anselm separates morality from happiness, and I provide a sketch of his alternative view. First, I argue against some recent (...) perspectives that Anselm maintained Eudaemonism. To do so, I provide a non-Eudaemonist reading of the two key passages and show how Eudaemonist readings are lacking in different respects. Second, I examine what this argument means for Anselm’s understanding of happiness and moral obligation. While there are some Eudaemonist themes in Anselm’s thinking, he flatly denies and revises aspects of the system. (shrink)

A probability distribution is regular if no possible event is assigned probability zero. While some hold that probabilities should always be regular, three counter-arguments have been posed based on examples where, if regularity holds, then perfectly similar events must have different probabilities. Howson (2017) and Benci et al. (2016) have raised technical objections to these symmetry arguments, but we see here that their objections fail. Howson says that Williamson’s (2007) “isomorphic” events are not in fact isomorphic, but Howson is speaking (...) of set-theoretic representations of events in a probability model. While those sets are not isomorphic, Williamson’s physical events are, in the relevant sense. Benci et al. claim that all three arguments rest on a conflation of different models, but they do not. They are founded on the premise that similar events should have the same probability in the same model, or in one case, on the assumption that a single rotation-invariant distribution is possible. Having failed to refute the symmetry arguments on such technical grounds, one could deny their implicit premises, which is a heavy cost, or adopt varying degrees of instrumentalism or pluralism about regularity, but that would not serve the project of accurately modelling chances. (shrink)

This paper defends an intellectualist interpretation of Diotima’s speech in Plato’s Symposium. I argue that Diotima’s purpose, in discussing the lower lovers, is to critique their erōs as aimed at a goal it can never secure, immortality, and as focused on an inferior object, themselves. By contrast, in loving the form of beauty, the philosopher gains a mortal sort of completion; in turning outside of himself, he also ceases to be preoccupied by his own incompleteness.

Newton published his deduction of universal gravity in Principia (first ed., 1687). To establish the universality (the particle-to-particle nature) of gravity, Newton must establish the additivity of mass. I call ‘additivity’ the property a body's quantity of matter has just in case, if gravitational force is proportional to that quantity, the force can be taken to be the sum of forces proportional to each particle's quantity of matter. Newton's argument for additivity is obscure. I analyze and assess manuscript versions of (...) Newton's initial argument within his initial deduction, dating from early 1685. Newton's strategy depends on distinguishing two quantities of matter, which I call ‘active’ and ‘passive’, by how they are measured. These measurement procedures frame conditions on the additivity of each quantity so measured. While Newton has direct evidence for the additivity of passive quantity of matter, he does not for that of the active quantity. Instead, he tries to infer the latter from the former via conceptual analyses of the third law of motion grounded largely on analogies to magnetic attractions. The conditions needed to establish passive additivity frustrate Newton's attempted inference to active additivity. (shrink)

The collapse of society is inevitable, even if it is in the distant future. When it collapses, it is likely to do so within the lifetimes of some people. These people will have matured in pre-collapse society, experience collapse, and then live the remainder of their lives in the post-collapse world. I argue that this group of people—the transitional generation—will be the worst off from societal collapse, far worse than subsequent generations. As the transitional generation, they will suffer disparately. This (...) intergenerational disparity in suffering is inequitable. Given that other disparities in suffering are worthy of remediation, this intergenerational disparity in suffering is worthy of remediation. However, the only way to do so is to target the mental states of the members of the transitional generation. (shrink)

In this chapter, I offer an overview of current scholarly debates on Plato's Lysis. I also argue for my own interpretation of the dialogue. In the Lysis, Socrates argues that all love is motivated by the desire for one’s own good. This conclusion has struck many interpreters as unattractive, so much so that some attempt to reinterpret the dialogue, such that it either does not offer an account of interpersonal love, or that it offers an account on which love is, (...) in fact, an other-regarding state. Others, notably Vlastos, criticize Socrates’ theory as implausibly and repellently egoistic. I maintain, against the first group, that Socrates is indeed offering an egoistic theory of love. I argue, against the second, that, while Socrates’ theory may be repellent, it possesses considerable explanatory power and avoids certain weaknesses which infect contemporary approaches to love. (shrink)

It is plausible that current generations owe something to future generations. One possibility is that we have a duty to not harm them. Another possibility is that we have a duty to protect them. In either case, however, to satisfy the duties to future generations from environmental or political degradation, we need to engage in widespread collective action. But, as we are, we have a limited ability to do so, in part because we lack the self-discipline necessary for successful collective (...) action. Given that having an obligation hinges on being able to satisfy it, the apparent duty to future generations is at odds with our apparent inability to satisfy it. Thus, we either need to rethink our duties to future generations or rethink the nature of our abilities. I argue in this chapter that we should rethink the nature of our abilities. Specifically, we should enhance our self-discipline, which is distinct from enhancements of motivation, judgment, or emotion. Even the most intelligent, motivated, and empathetic actor is likely to slip up, which encourages others to withdraw their cooperation. Without the necessary self-discipline to sustain our public cooperative behavior, collective action is likely to fail, leaving us with one alternative: to abandon our duties to future generations. (shrink)

This paper analyzes the apraxia argument in Cicero’s Academica. It proposes that the argument assumes two modes: the evidential mode maintains that skepticism is false, while the pragmatic claims that it is disadvantageous. The paper then develops a tension between the two modes, and concludes by exploring some differences between ancient and contemporary skepticism.

Despite the lack of evidence for their effectiveness, the use of physical restraints for patients is widespread. The best ethical justification for restraining patients is that it prevents them from harming themselves. We argue that even if the empirical evidence supported their effectiveness in achieving this aim, their use would nevertheless be unethical, so long as well known exceptions to informed consent fail to apply. Specifically, we argue that ethically justifiable restraint use demands certain necessary and sufficient conditions. These conditions (...) are that the physician obtain informed consent for their application, that their application be medically appropriate, and that restraints be the least liberty-restricting way of achieving the intended benefit. It is a further question whether their application is ever medically appropriate, given the dearth of evidence for their effectiveness. (shrink)

Moral bioenhancement is the potential practice of manipulating individuals’ moral behaviors by biological means in order to help resolve pressing moral issues such as climate change and terrorism. This practice has obvious ethical implications, and these implications have been and continue to be discussed in the bioethics literature. What have not been discussed are the epistemological implications of moral bioenhancement. This article details some of these implications of engaging in moral bioenhancement. The argument begins by making the distinction between moral (...) bioenhancement that manipulates the contents of mental states and that which manipulates other, non-representational states. Either way, I argue, the enhanced moral psychology will fail to conform to epistemic norms, and the only way to resolve this failure and allow the moral bioenhancement to be effective in addressing the targeted moral issues is to make the moral bioenhancement covert. (shrink)

We aim to establish the following claim: other factors held constant, the relative weights of the epistemic burdens of competing treatment options serve to determine the options that patient surrogates pursue. Simply put, surrogates confront an incentive, ceteris paribus, to pursue treatment options with respect to which their knowledge is most adequate to the requirements of the case. Regardless of what the patient would choose, options that require more knowledge than the surrogate possesses (or is likely to learn) will either (...) be neglected altogether or deeply discounted in the surrogate’s incentive structure. We establish this claim by arguing that the relation between epistemic burdens and incentives in decision-making is a general feature of surrogate decision-making. After establishing the claim, we draw out some of the implications for surrogate decision-making in medicine and offer philosophical and psychological explanations of the phenomenon. (shrink)

Augustine’s privation theory of evil maintains that something is evil in virtue of a privation, a lack of something which ought to be present in a particular nature. While it is not evil for a human to lack wings, it is indeed evil for a human to lack rationality according to the end of a rational nature. Much of the literature on the privation theory focuses on whether it can successfully defend against counterexamples of positive evils, such as pain. This (...) focus of the discussion is not surprising, given that the privation theory is a theory about the nature of evil. But it is also a theory that protects venerable theological concerns, namely, that God is the good creator of everything, and that everything is good. It is the purpose of this article to further this discussion on both fronts. I argue that the counterexample of pain still defeats the privation theory despite the most recent defense. What is more, I suggest, this is not theologically disastrous. The individual who rejects the privation theory is not obligated to reject the theological theses which motivate it. To show how a rejection of the privation theory is a live option, I offer an alternative view of evil that also maintains these theological theses and encompasses both privative and positive evils. (shrink)

In the Protagoras, Socrates argues that what appears to be akrasia is, in fact, the result of a hedonic illusion: proximate pleasures appear greater than distant ones. On the face of it, his account is puzzling: why should proximate pleasures appear greater than distant ones? Certain interpreters argue that Socrates must be assuming the existence of non-rational desires that cause proximate pleasures to appear inflated. In this paper, I argue that positing non-rational desires fails to explain the hedonic error. However, (...) careful consideration of Socrates’ treatment of appearances reveals that he is not without resources to explain the illusion. I argue that in the Protagoras, appearances are imagistic mental representations that appear true but tend to be false. I suggest that proximate pleasures produce inflated hedonic predictions because we represent them more vividly than distant ones, yielding greater anticipatory pleasure which causes us to overestimate their magnitude. (shrink)

Humans are morally deficient in a variety of ways. Some of these deficiencies threaten the continued existence of our species. For example, we appear to be incapable of responding to climate change in ways that are likely to prevent the consequent suffering. Some people are morally better than others, but we could all be better. The price of not becoming morally better is that when those events that threaten us occur, we will suffer from them. If we can prevent this (...) suffering from occurring, then we ought to do so. That we ought to make ourselves morally better in order to prevent very bad things from happening justifies, according to some, the development and administration of moral enhancement. I address in this paper the idea that moral enhancement could give rise to moral transhumans, or moral post-persons. Contrary to recent arguments that we shouldn’t engender moral post-persons, I argue that we should. Roughly, the reasons for this conclusion are that we can expect moral post-persons to resemble the morally best of us, our moral exemplars. Since moral exemplars promote their interests by promoting the interests of others (or they promote others’ interests at the expense of their own) we can expect moral post-persons to pursue our interests. Since we should also pursue our own interests, we should bring about moral post-persons. (shrink)

Default positions, predetermined starting points that aid in complex decision-making, are common in clinical medicine. In this article, we identify and critically examine common default positions in clinical ethics practice. Whether default positions ought to be held is an important normative question, but here we are primarily interested in the descriptive, rather than normative, properties of default positions. We argue that default positions in clinical ethics function to protect and promote important values in medicine—respect for persons, utility, and justice. Further, (...) default positions in clinical ethics may also guard against harm. Where default positions exist, there are epistemic burdens to overturn them. The person wishing to reject the default position, rather than the person endorsing it, bears this burden. The person who bears the burden of meeting the epistemic requirements must provide evidence proportional to the degree of harm the default position protects against. Default positions that protect against significant harm impose significant epistemic requirements to overturn. This asymmetry not only makes medical decision-making more economical but also serves to promote and protect certain values. The identification and analysis of common and recognizable default positions can help to identify other default positions and the conditions under which their associated epistemic requirements are met. The article concludes with considerations of potential problems with the use of default positions in clinical ethics. (shrink)

One of the ways in which Plato has captured the popular imagination is with the claim that the philosopher can feel erôs, passionate love, for the objects of knowledge. Why should Plato make this claim? In this chapter, I explore Plato’s treatment of philosophical erôs along three dimensions. First, I consider the source of philosophical erôs. I argue that it is grounded in our mortality and imperfection, which give rise to a desire for immortality and the immortal. Second, I turn (...) to the object of philosophical erôs. I suggest that it is an arresting response to beauty, through which we come to value the ideal properties of the forms. Finally, I address the nature of erôs. I claim that it is a focusing desire, that overrides other concerns and causes us to overwhelmingly focus on its object. I conclude the chapter by considering the problem Vlastos famously raises for Plato’s account of erôs: can it do justice to disinterested, interpersonal love? In agreement with Vlastos, I claim that one who comes to grasp the forms will cease to feel interpersonal love; however, I also suggest that erôs can give rise to philia, beneficent concern with the wellbeing of others. (shrink)

According to Plato's successors, assimilation to god (homoiosis theoi) was the end (telos) of the Platonic system. There is ample evidence to support this claim in dialogues ranging from the Symposium through the Timaeus. However, the Philebus poses a puzzle for this conception of the Platonic telos. On the one hand, Plato states that the gods are beings beyond pleasure while, on the other hand, he argues that the best human life necessarily involves pleasure. In this paper, I argue that (...) the solution to this puzzle lies in the fact that the processes by which we assimilate to god, learning and becoming virtuous, are restitutive and hence pleasant. Thus, the reason why the best human life necessarily involves pleasure is that we can never become fully divine and perfect, but must constantly strive to become like the divine, through pleasureful restitutive processes. In this paper, I also provide a close examination and taxonomy of the different models that Plato presents throughout his corpus of assimilation to god. -/- Note: "Fleeing the Divine" (Philebus: Selected Papers from the VIII Symposium Platonicum) is an earlier, shorter version of this paper. (shrink)

It has recently been argued that a person’s moral judgments (about both their own and others’ actions) are constrained by the nature and extent of their relevant ignorance and, thus, that such judgments are determined in the first instance by the person’s epistemic circumstances. It has been argued, in other words, that the epistemic is logically prior to other normative (e.g., ethical, prudential, pecuniary) considerations in human decision-making, that these other normative considerations figure in decision-making only after (logically and temporally) (...) relevant ignorance has constrained the decision-maker’s menu of options. If this is right, then a person’s moral judgments in some set of circumstances should vary with their knowledge and ignorance of these circumstances. In this study, we test the hypothesis of the logical priority of the epistemic. We describe two experiments in which subjects’ knowledge and ignorance of relevant consequences were manipulated. In the second experiment, we also compared the effect of ignorance on moral judgments with that of personal force, a factor previously shown to influence moral judgments. We found broad empirical support for the armchair arguments that epistemic considerations are logically prior to normative considerations. (shrink)

Berger (forthcoming) states that moral intimacy is important in applying the best interests standard. But what he calls moral intimacy requires that someone has overcome epistemic burdens needed to represent the patient. We argue elsewhere that good surrogate decision-making is first and foremost a matter of overcoming epistemic burdens, or those obstacles that stand in the way of a surrogate decision-maker knowing what a patient wants and how to satisfy those preferences. Berger’s notion of moral intimacy depends on epistemic intimacy: (...) the fact that a surrogate's epistemic burdens with respect to the best interests of the incapacitated patient have been adequately surmounted, plus some other feature. Thus, where a particular patient-surrogate relationship fails to be morally intimate, what is lacking is either epistemic intimacy or this second feature. Furthermore, Berger uses the notion of moral intimacy as an explanans for the application of the best interests standard. We argue that the notions of epistemic intimacy and epistemic burdens not only help to explain the notion of moral intimacy, but also better explain the application of the best interests standard. Given the role of epistemic burdens and the epistemic intimacy that overcoming them enables, bioethicists and physicians should consider a surrogate’s epistemic standing relative to the patient’s best interests before pronouncing on the former’s ethical probity. (shrink)

As the science and technology of the brain and mind develop, so do the ways in which brains and minds may be surveilled and manipulated. Some cognitive libertarians worry that these developments undermine cognitive liberty, or “freedom of thought.” I argue that protecting an individual’s cognitive liberty undermines others’ ability to use their own cognitive liberty. Given that the threatening devices and processes are not relevantly different from ordinary and frequent intrusions upon one’s brain and mind, strong protections of cognitive (...) liberty may proscribe neurotechnological intrusions, but also ordinary intrusions. Thus, the cognitive libertarian position “hog-ties” others’ use of their own liberties. This problem for the cognitive libertarian is the same problem that ordinary libertarianism faces in protecting individual rights to property and person. But the libertarian strategies for resolving the problem don’t work for the cognitive libertarian. I conclude that the right to mental privacy is weaker than what cognitive libertarians want it to be. (shrink)

In a recent issue of Bioethics, I argued that compulsory moral bioenhancement should be administered covertly. Alexander Zambrano has criticized this argument on two fronts. First, contrary to my claim, Zambrano claims that the prevention of ultimate harm by covert moral bioenhancement fails to meet conditions for permissible liberty‐restricting public health interventions. Second, contrary to my claim, Zambrano claims that covert moral bioenhancement undermines autonomy to a greater degree than does overt moral bioenhancement. In this paper, I rebut both of (...) these arguments, then finish by noting important avenues of research that Zambrano’s arguments motivate. (shrink)

In this paper I’ll examine whether we could be justified in attributing consciousness to artificial intelligent systems. First, I’ll give a brief history of the concept of artificial intelligence (AI) and get clear on the terms I’ll be using. Second, I’ll briefly review the kinds of AI programs on offer today, identifying which research program I think provides the best candidate for machine consciousness. Lastly, I’ll consider the three most plausible ways of knowing whether a machine is conscious: (1) an (...) AI demonstrates a sufficient level of organizational similarity to that of a human thinker, (2) an inference to the best explanation, and (3) what I call “punting to panpsychism”, i.e., the idea that if everything is conscious, then we get machine consciousness in AI for free. However, I argue that all three of these methods for attributing machine consciousness are inadequate since they each face serious philosophical problems which I will survey and specifically tailor to each method. (shrink)

In standard probability theory, probability zero is not the same as impossibility. But many have suggested that only impossible events should have probability zero. This can be arranged if we allow infinitesimal probabilities, but infinitesimals do not solve all of the problems. We will see that regular probabilities are not invariant over rigid transformations, even for simple, bounded, countable, constructive, and disjoint sets. Hence, regular chances cannot be determined by space-time invariant physical laws, and regular credences cannot satisfy seemingly reasonable (...) symmetry principles. Moreover, the examples here are immune to the objections against Williamson’s infinite coin flips. (shrink)

With essay deadlines looming for many of our students, Matt Parker relives some of the angst involved in writing philosophy. You’re not alone.

In dialogues ranging from the Symposium to the Timaeus, Plato appears to propose that the philosopher’s grasp of the forms may confer immortality upon him. Whatever can Plato mean in making such a claim? What does he take immortality to consist in, such that it could constitute a reward for philosophical enlightenment? And how is this proposal compatible with Plato’s insistence throughout his corpus that all soul, not just philosophical soul, is immortal? In this chapter, I pursue these questions by (...) applying the distinction between general and earned immortality to the Phaedo and the Symposium. I argue that, while Plato attributes general immortality to all soul in the Phaedo, in the Affinity Argument, he proposes that the philosopher’s soul can achieve earned immortality through contemplating forms. It is this form of immortality that Plato claims is unavailable to humankind in the flux passage of the Symposium. At the same time, in the ascent passage, he holds out the possibility – albeit with significant reservations – that the philosopher’s soul may transcend its humanity and achieve earned immortality through its communion with the form. (shrink)

The puzzle of petitionary prayer: if we ask for the best thing, God was already going to do it, and if we ask for something that's not the best, God's not going to grant our request. In this paper, we give a new solution to the puzzle.

In biomedical ethics, there is widespread acceptance of moral realism, the view that moral claims express a proposition and that at least some of these propositions are true. Biomedical ethics is also in the business of attributing moral obligations, such as “S should do X.” The problem, as we argue, is that against the background of moral realism, most of these attributions are erroneous or inaccurate. The typical obligation attribution issued by a biomedical ethicist fails to truly capture the person's (...) actual obligations. We offer a novel argument for rife error in obligation attribution. The argument starts with the idea of an epistemic burden. Epistemic burdens are all of those epistemic obstacles one must surmount in order to achieve some aim. Epistemic burdens shape decision-making such that given two otherwise equal options, a person will choose the option that has the lesser of epistemic burdens. Epistemic burdens determine one's potential obligations and, conversely, their non-obligations. The problem for biomedical ethics is that ethicists have little to no access to others' epistemic burdens. Given this lack of access and the fact that epistemic burdens determine potential obligations, biomedical ethicists often can only attribute accurate obligations out of luck. This suggests that the practice of attributing obligations in biomedical ethics is rife with error. To resolve this widespread error, we argue that this practice should be abolished from the discourse of biomedical ethics. (shrink)

Many people find the manipulation of the human germline—editing the DNA of sperm or egg cells such that these genetic changes are passed to the resulting offspring—to be morally impermissible. In this paper, I argue for the claim that editing the human germline is morally permissible. My argument starts with the claim that outcome uncertainty regarding the effects of germline editing shows that the duty to not harm cannot ground the prohibition of germline editing. Instead, if germline editing is wrong, (...) it is wrong because it violates a duty to protect. However, we also have an epistemic duty to gather evidence regarding the effects of editing the human germline which overrides any moral duty to protect future generations. Thus, we have a duty to gather evidence regarding the effects of editing the human germline, which is to say that we have a duty to edit the human germline. (shrink)

In this paper, I explore parallels between philosophical and tyrannical eros in Plato's Republic. I argue that in arguing that reason experiences eros for the forms, Plato introduces significant tensions into his moral psychology.

Note: "Next to Godliness" (Apeiron) is an expanded version of this paper. -/- According to Plato's successors, assimilation to god (homoiosis theoi) was the end (telos) of the Platonic system. There is ample evidence to support this claim in dialogues ranging from the Symposium through the Timaeus. However, the Philebus poses a puzzle for this conception of the Platonic telos. On the one hand, Plato states that the gods are beings beyond pleasure while, on the other hand, he argues that (...) the best human life necessarily involves pleasure. In this paper, I argue that the solution to this puzzle lies in the fact that the processes by which we assimilate to god, learning and becoming virtuous, are restitutive and hence pleasant. Thus, the reason why the best human life necessarily involves pleasure is that we can never become fully divine and perfect, but must constantly strive to become like the divine, through pleasureful restitutive processes. In this paper, I also provide a close examination and taxonomy of the different models that Plato presents throughout his corpus of assimilation to god. (shrink)

We thank all the thoughtful authors for their insightful comments. In this response, we try to address some of themes that emerged from the commentaries. We leave aside some of those comments that...

Most current dental ethics curricula use a deontological approach to biomedical and dental ethics that emphasizes adherence to duties and principles as properties that determine whether an act is ethical. But the actual ethical orientation of students is typically unknown. The purpose of the current study was to determine the ethical orientation of dental students in resolving clinical ethical dilemmas. First-year students from one school were invited to participate in an electronic survey that included eight vignettes featuring ethical conflicts common (...) to the health care setting. The Multidimensional Ethics Scale was used to evaluate the students’ ethical judgments of these conflicts. Students rated each vignette along 13 ethically relevant items using a 7-point scale. Nine of the thirteen items were analyzed because they represent the dominant ethical theories, including deontology. One hundred sixteen dental students successfully completed the survey. Of the analyzed items, those associated with deontology had comparatively weak associations with whether students judged the action to be ethical and whether students judged themselves likely to perform the action. Whether an action was judged to be caring had the strongest association with whether the action was judged to be ethical and whether students judged themselves likely to perform the action. These results suggest that adherence to duties or principles has weaker association with students’ ethical judgments and behavior compared to caring, which was found to be more influential in their ethical judgments and behavior. Current dental school curricula with a primary focus on deontology may no. (shrink)