The aim of this paper lies in characterizing the explanations and models used in the field of evolutionary developmental biology throughout its history. While manipulative experiments in controlled conditions have been useful to set the bases of the discipline and are still routinely performed, this approach supposes a tension between the reliability and the representativity of the conclusions. Given the recent changes in the understanding of evolutionary phenomena, different authors currently emphasize the need of avoiding excessive simplifications in experimental approaches, (...) incorporating the complexity of the analyzed systems as a relevant trait in the study of biological diversity. On the other hand, the fragile and contingent nature of evolutionary processes and the impossibility of intervening some of these phenomena underscore the importance of non-manipulative models that allow the elucidation of how-possibly mechanisms. We argue that a pluralism characterized by the integration of different kinds of explanations, models and metaphors used in evo-devo allows to exploit their respective advantages, favours interdisciplinarity and can contribute to form a representative description of evolutionary processes without relinquishing the local and detailed study of actual mechanisms. (shrink)

Una interpretación particularmente influyente de la teoría de la implicación lógica de Bertrand Russell y Clarence I. Lewis es la propuesta por Quine en su artículo “Reply to Professor Marcus”. Allí Quine sostiene que la lógica modal de Lewis nació en pecado: el pecado de confundir uso con mención, ya que cuando se afirma que una oración implica lógicamente a otra, estas oraciones no están siendo usadas sino mencionadas. Según la interpretación de Quine, Clarence I. Lewis persistió en el error (...) de Russell, que consistió en confundir la implicación material con la implicación lógica, y confundió la implicación estricta con la implicación lógica. Estos ‘pecados’ de Russell y Lewis pueden entenderse mejor si se tiene en cuenta que tanto Lewis como Russell sostienen que los axiomas y los teoremas en un cálculo lógico se usan de dos maneras: (a) como premisas a partir de las cuales se obtienen nuevos teoremas, y (b) como reglas de inferencia mediante las cuales se obtienen nuevos teoremas. En efecto, estos autores suscriben la teoría del doble uso de los principios lógicos que parece originarse en la obra de Peano y que ha sido casi completamente ignorada en la literatura acerca de la historia de la lógica. -/- A particularly influential interpretation of Bertrand Russell’s and Clarence I. Lewis’s theory of logical implication is the one proposed by Quine in his article "Reply to Professor Marcus". In that article Quine argues that Lewis's modal logic was born in sin: the sin of confusing use with mention, since when it is stated that a sentence logically implies another sentence, these sentences are not being used but mentioned. According to Quine's interpretation, Clarence I. Lewis persisted in Russell's error, which consisted in confusing material implication with logical implication, and confused strict implication with logical implication. These 'sins' of Russell and Lewis can be better understood if we take into account that both logicians argue that the axioms and theorems in a logical calculus are used in two ways: (a) as premises from which new theorems are obtained, and (b) as rules of inference by which new theorems are obtained. In fact, these authors subscribe to the theory of the double use of logical principles that seems to originate in Peano's work and that has been almost completely ignored in the literature about the history of logic. (shrink)