In this paper, we present a way to translate the metainferences of a mixed metainferential system into formulae of an extended-language system, called its associated σ-system. To do this, the σ-system will contain new operators (one for each standard), called the σ operators, which represent the notions of "belonging to a (given) standard". We first prove, in a model-theoretic way, that these translations preserve (in)validity. That is, that a metainference is valid in the base system if and only if its (...) translation is a tautology of its corresponding σ-system. We then use these results to obtain other key advantages. Most interestingly, we provide a recipe for building unlabeled sequent calculi for σ-systems. We then exemplify this with a σ-system useful for logics of the ST family, and prove soundness and completeness for it, which indirectly gives us a calculus for the metainferences of all those mixed systems. Finally, we respond to some possible objections and show how our σ-framework can shed light on the “obeying” discussion within mixed metainferential contexts. (shrink)

In this article, I examine the issue of the alleged circularity in the determination of homologies within cladistic analysis. More specifically, I focus on the claims made by the proponents of the dynamic homology approach, regarding the distinction (sometimes made in the literature) between primary and secondary homology. This distinction is sometimes invoked to dissolve the circularity issue, by upholding that characters in a cladistic data matrix have to be only primarily homologous, and thus can be determined independently of phylogenetic (...) hypotheses, by using the classical Owenian criteria (for morphological characters) or via multiple sequence alignment (for sequence data). However, since in the dynamic approach, sequence data can be analyzed without being pre-aligned, proponents have claimed that the distinction between primary and secondary homology has no place within cladistics. I will argue that this is not the case, since cladistic practice within the dynamic framework does presuppose primary homology statements at a higher level. (shrink)

An interesting metatheoretical controversy took place during the 1980’s and 1990’s between pattern and phylogenetic cladists. What was always at stake in the discussion was not how work in systematics should be carried out, but rather how this practice should be metatheoretically interpreted. In this article, we criticize Pearson’s account of the metatheoretical factors at play in this discussion. Following him, we focus on the issue of circularity, and on the role that phylogenetic hypotheses play in the determination of “primary (...) homologies”. Pearson argues that the recognition of primary homologies cannot be achieved without recourse to previous phylogenetic knowledge, and that to claim otherwise is to state that primary homologies are observable. To show why that view would be inadequate, he appeals to Hanson’s views about theory-laden observation, alongside with a specific case study, which allegedly illustrates the more complex relation between observation and theory. We will argue that the pattern cladists’ point is better addressed by taking a quite different approach: instead of thinking in terms of observability, the topic can be tackled by paying attention to the way in which concepts are determined. We will take the notion of T-theoricity from metatheoretical structuralism and show that, once the issue is discussed with the appropriate metatheoretical framework, the alleged counterexample brought up by Pearson is not problematic at all for pattern cladism. (shrink)

The propensity account of fitness intends to solve the classical tautologicity issue by identifying fitness with a disposition, the ability to survive and reproduce. As proponents recognized early on, this account requires operational independence from actual reproductive success to avoid circularity and vacuousness charges. They suggested that operational independence is achieved by measuring fitness values through optimality models. Our goal in this article is to develop this suggestion. We show that one plausible procedure by which these independent operationalizations could be (...) thought to take place, and which is in accordance with what is said in the optimality literature, is unsound. We provide two independent lines of reasoning to show this. We then provide a sketch of a more adequate account of the role of optimality models in evolutionary contexts and draw some consequences. (shrink)

The adequacy of Elliott Sober’s analogy between classical mechanics and evolutionary theory—according to which both theories explain via a zero-force law and a set of forces that alter the zero-force state—has been criticized from various points of view. I focus here on McShea and Brandon’s claim that drift shouldn’t be considered a force because it is not directional. I argue that there are a number of different theses that could be meant by this, and show that one of those theses—the (...) idea that drift cannot bias populations to be taken somewhere in the evolutionary space from one generation to the next—is actually false. Not only has this thesis been implicitly assumed in the discussion of the force analogy thus far, but it is also commonly found in a wider range of philosophical and biological texts. I argue that correcting this view, and the usual images associated with it, will thereby bring heuristic benefits that impact the force analogy discussion, but that also go beyond it. (shrink)

In this article, I develop three conceptual innovations within the area of formal metatheory, and present a computer program, called Reconstructor, that implements those developments. The first development consists in a methodology for testing formal reconstructions of scientific theories, which involves checking both whether translations of paradigmatically successful applications into models satisfy the formalisation of the laws, and also whether unsuccessful applications do not. I show how Reconstructor can help carry this out, since it allows the end-user to specify a (...) formal language, input axioms and models formulated in that language, and then ask if the models satisfy the axioms. The second innovation is the introduction of incomplete models (for which the denotation of some terms is missing) into scientific metatheory, in order to represent cases of missing information. I specify the paracomplete semantics built into Reconstructor to deal with sentences where denotation failures occur. The third development consists in a new way of explicating the structuralist notion of a determination method, by equating them with algorithms. This allows determination methods to be loaded into Reconstructor and then executed within a model to find out the value of a previously non-denoting term (i.e. it allows the formal reconstruction to make predictions). This, in turn, can help test the reconstruction in a different way. Finally, I conclude with some suggestions about additional uses the program may have. (shrink)

The observational-theoretical distinction has played a central role in the philosophy of science from logical empiricism onwards. Developments within the discipline have shown that such a distinction hides two non-identical distinctions: observational vs. non-observational and theoretical vs. non-theoretical. Likewise, metatheoretical structuralism proposed a more sophisticated treatment of theoricity in terms of the operational dependence or independence of concepts from the theories in which they appear. Despite this remarkable sophistication, it is still generally accepted that the distinction between theoretical and non-theoretical (...) concepts coincides with the explanatory vs. non-explanatory and testing vs. non-testing distinctions. Ginnobili and Carman argued for the independence between theoricity and explanation. In this paper we will focus on testing and argue for its independence from both theoricity and explanation. To do so, we propose an account of theory testing based on the framework of metatheoretical structuralism and apply it to natural selection theory and cladistics. (shrink)

En un libro reciente McShea y Brandon defienden que la diversidad y la complejidad de la vida se explican, principalmente, por la acción de un principio que llaman “la ley evolutiva de fuerzas cero” o “ZFEL”. Tal principio actuaría de un modo implícito por detrás de muchas explicaciones de la biología, pero nunca habría sido explicitado. Asumiendo que esta idea es interesante, y que los autores en cuestión tienen razón, discutiremos el modo metateórico en que presentan dicho principio, como siendo (...) parte de la teoría de la probabilidad. Esto permite a los autores afirmar que la teoría de la probabilidad brindaría la base reductiva para toda la biología evolutiva (dado que consideran que otros principios, como el de selección natural, también serían parte de la teoría de la probabilidad). Defenderemos que, efectivamente, ZFEL no es propio de la biología únicamente, pero no por formar parte de la teoría de la probabilidad, sino por tratarse de una versión específica del principio de causa común. -/- In a recent book, McShea and Brandon argue that the observed diversity and complexity of life are explainable by a principle they call the “zero-force evolutionary law” or “ZFEL”. Although this principle would be implicit in many explanations given by biologists, it would have never been made explicit. Assuming that this idea is interesting, and that the authors are right, we will discuss the metatheoretical way in which they present said principle, as being a part of probability theory. This allows the authors to claim that probability theory provides the reductive basis for all evolutionary biology. We will defend, in accordance with them, that ZFEL is not a solely biological principle, but not because it is a part of probability theory, but rather because it is a specific version of the principle of common cause. (shrink)

A given explanatory theory T falls into circular reasoning if the only way to determine its explanandum is through the application of T. To find an underlying theory T′ that determines T′s explanandum helps us save T from this accusation of circularity. We follow the structuralist view of theories in presenting and dealing with this issue, by applying it to particular theories. More specifically, we focus on the relationship between the Darwinian theory of common ancestry and the determination of homologies.

Resumen -/- El objetivo de este trabajo consiste en analizar las relaciones entre los modelos de optimalidad y la selección natural. Defenderemos que esas relaciones pueden dividirse en dos tipos, en tanto hay dos tipos de explicaciones seleccionistas, que llamaremos “históricas” y “ahistóricas”. Las explicaciones históricas revelan como una población dada adquiere un rasgo que es adaptativo en ese ambiente e involucran muchas generaciones, variación, etc. Las explicaciones ahistóricas, explican por qué, en determinado momento, ciertos tipos de organismos tienen un (...) mayor éxito reproductivo que otros. Mostraremos que los modelos de optimalidad pueden jugar un rol en la determinación del explanandum de las explicaciones histórica seleccionistas, esto es, que ayudan a reconocer qué rasgos son adaptativos. Por otra parte, mostramos que los modelos de optimalidad nos permiten determinar a veces la parte del explanans de las explicaciones ahistóricas (particularmente, el concepto de fitness). -/- Abstract -/- The goal of this paper is to analyze the relations between optimality models and natural selection. We contend that these relationships can be divided into two kinds, as there are two kinds of natural selection explanations, which we call “historical” and “ahistorical”. Historical explanations reveal how a given population acquires a trait which is adaptive in its environment, and involves many generations, variations, etc. Ahistorical ones, explain why, at a given moment, certain kinds of organisms have a greater reproductive success than others. We show that optimality models can play a role in determining the explanandum of historical selectionist explanations, that is, they help us to recognize which traits are adaptive. And, on the other hand, that optimality models sometimes allow us to determine part of the explanans of ahistorical explanations (particularly, the concept of fitness). (shrink)

How questions and why questions interact in complex ways within biological practice. One of the most fruitful accounts to think about this relation is the widely known systemic approach, which has its origin mainly in the works of Robert Cummins (1975, 1983). As we will show, this approach effectively manages to capture much of what biologists do, especially in areas such as molecular biology, neuroscience and neuroethology. Our aim with this work is to discuss the metatheoretical status of the presuppositions (...) behind systemic analysis. We will hold that these assumptions are of an empirical nature, and that they can be reconstructed as parts of a theory. (shrink)

The present work analyzes the controversy within biological systematics regarding the status of cladistics. The use of the parsimony method for phylogenetic reconstruction has been defended by appealing to a methodological principle of simplicity, as well as to empirical principles that external to systematics. I propose new kind of approach, which consists in considering it an empirical theory, thus justifying its application by its empirical success. To defend this point, a formal structuralist reconstruction of cladistics will be provided, which will (...) help clarify what its central empirical statements are. At the same time, I show how these principles have been used to test that theory using experimental phylogenies. (shrink)

In this paper, we examine the issue of the empirical or non-empirical status of philosophical metatheories. In particular, we ask whether a specific type of metatheoretical product, formal reconstructions of scientific theories, can be empirically tested. To answer this, we take Metatheoretical Structuralism as a metatheory and Classical Mechanics as our case studies. We show how classical mechanics can be reconstructed from structuralism. We then present a computer program, called Reconstructor, and show how it can be used to test the (...) adequacy of the reconstruction. Finally, we discuss some philosophical points regarding these tests, namely, the issues of holism, circularity and metatheoretical predictions. (shrink)

El objetivo de este trabajo consiste en analizar las relaciones entre los modelos de optimalidad y la selección natural. Defenderemos que esas relaciones pueden dividirse en dos tipos, en tanto hay dos tipos de explicaciones seleccionistas, que llamaremos “históricas” y “ahistóricas”. Las explicaciones históricas revelan como una población dada adquiere un rasgo que es adaptativo en ese ambiente e involucran muchas generaciones, variación, etc. Las explicaciones ahistóricas, explican por qué, en determinado momento, ciertos tipos de organismos tienen un mayor éxito (...) reproductivo que otros. Mostraremos que los modelos de optimalidad pueden jugar un rol en la determinación del explanandum de las explicaciones histórica seleccionistas, esto es, que ayudan a reconocer qué rasgos son adaptativos. Por otra parte, mostramos que los modelos de optimalidad nos permiten determinar a veces la parte del explanans de las explicaciones ahistóricas (particularmente, el concepto de fitness). The goal of this paper is to analyze the relations between optimality models and natural selection. We contend that these relationships can be divided into two kinds, as there are two kinds of natural selection explanations, which we call “historical” and “ahistorical”. Historical explanations reveal how a given population acquires a trait which is adaptive in its environment, and involves many generations, variations, etc. Ahistorical ones, explain why, at a given moment, certain kinds of organisms have a greater reproductive success than others. We show that optimality models can play a role in determining the explanandum of historical selectionist explanations, that is, they help us to recognize which traits are adaptive. And, on the other hand, that optimality models sometimes allow us to determine part of the explanans of ahistorical explanations (particularly, the concept of fitness). (shrink)

This article elaborates on McShea and Brandon’s idea that drift is unlike the rest of the evolutionary factors because it is constitutive rather than imposed on the evolutionary process. I show that the way they spelled out this idea renders it inadequate and is the reason why it received some objections. I propose a different way in which their point could be understood, that rests on two general distinctions. The first is a distinction between the underlying mathematical apparatus used to (...) formulate a theory and a concept proposed by that theory. With the aid of a formal reconstruction of a population genetic model, I show that drift belongs to the first category. That is, that drift is constitutive of population genetics in the same sense that multiplication is constitutive in classical mechanics, or that circle is constitutive in Ptolemaic astronomy. The second distinction is between eliminating a concept from a theory and setting its value to zero. I will show that even though drift can be set to zero just like the rest of the evolutionary factors, eliminating drift is much harder than eliminating those other factors, since it would require changing the entire mathematical apparatus of standard population genetic theory. I conclude by drawing some other implications from the proposed formal reconstruction. (shrink)

This article elaborates on McShea and Brandon’s idea that drift is unlike the rest of the evolutionary factors because it is constitutive rather than imposed on the evolutionary process. I show that the way they spelled out this idea renders it inadequate and is the reason why it received some objections. I propose a different way in which their point could be understood, that rests on two general distinctions. The first is a distinction between the underlying mathematical apparatus used to (...) formulate a theory and a concept proposed by that theory. With the aid of a formal reconstruction of a population genetic model, I show that drift belongs to the first category. That is, that drift is constitutive of population genetics in the same sense that multiplication is constitutive in classical mechanics, or that circle is constitutive in Ptolemaic astronomy. The second distinction is between eliminating a concept from a theory and setting its value to zero. I will show that even though drift can be set to zero just like the rest of the evolutionary factors, eliminating drift is much harder than eliminating those other factors, since it would require changing the entire mathematical apparatus of standard population genetic theory. I conclude by drawing some other implications from the proposed formal reconstruction. (shrink)

In this article, we defend that incorporating a rejection operator into a paraconsistent language involves fully specifying its inferential characteristics within the logic. To do this, we examine a recent proposal by Berto for a paraconsistent rejection, which — according to him — avoids paradox, even when introduced into a language that contains self-reference and a transparent truth predicate. We will show that this proposal is inadequate because it is too incomplete. We argue that the reason it avoids trouble is (...) that the inferential characteristics of the new operator are left unspecified, exporting the task of specifying them to metaphysicians. Additionally, we show that when completing this proposal with some plausible rules for the rejection operator, paradoxes do arise. Finally, we draw some more general implications from the study of this example. (shrink)

Es una opinión extendida que la teoría de la selección natural, tal como fue formulada originalmente por Darwin de manera “cualitativa”, ha sido reemplazada por una versión cuantitativa superior, brindada por la genética de poblaciones. En este artículo se discute contra esa tesis, sosteniendo en cambio que ambas teorías son complementarias, no sucesivas. Para ello, se introduce una línea de argumentación novedosa, que toma su inspiración en la crítica al “inductivismo estrecho” de Hempel. Se sostiene que los genetistas de poblaciones (...) serían incapaces de aplicar exitosamente su teoría sin hipótesis “ecológicas” preconcebidas, provenientes de la teoría darwiniana, que permitan particionar a la población en rasgos selectivamente relevantes. Se enfatiza además que la falla en notar este punto se debe a una mala comprensión de la estructura de la teoría darwiniana y de su ley o principio fundamental. A la luz de una mejor reconstrucción de dicho principio, se reexamina en mayor detalle la relación existente entre ambas teorías. (shrink)

In this article, we provide three generators of propositional formulae for arbitrary languages, which uniformly sample three different formulae spaces. They take the same three parameters as input, namely, a desired depth, a set of atomics and a set of logical constants (with specified arities). The first generator returns formulae of exactly the given depth, using all or some of the propositional letters. The second does the same but samples up-to the given depth. The third generator outputs formulae with exactly (...) the desired depth and all the atomics in the set. To make the generators uniform (i.e. to make them return every formula in their space with the same probability), we will prove various cardinality results about those spaces. (shrink)

El objetivo de este artículo es analizar qué quiere decir capturar una teoría (se utilizará la aritmética como ejemplo paradigmático) por medio de un sistema axiomático formal. Se considerarán para ello dos enfoques, que pueden denominarse “semántico” y “sintáctico”, tanto en términos de sus ventajas como de sus limitaciones. El enfoque semántico (presupuesto por Barrio y Da Ré en este volumen y expuesto en la primera sección), entiende la expresabilidad como una restricción de la clase de los modelos; se muestra (...) que esta concepción lleva a tres clases distintas de limitaciones expresivas. En la segunda sección se examinan -y finalmente rechazan- algunos posibles caminos de solución a estos problemas. En la última sección se ofrecen objeciones a las alternativas restantes y en base a ellas se elabora el enfoque sintáctico que liga la noción de captura a la de prueba de las oraciones relevantes. También se argumenta que desde este marco pueden evitarse algunas de las limitaciones del enfoque semántico. (shrink)

En este artículo sostenemos que, en aquellos casos en los cuales la capacidad _ explanandum _ de un análisis sistémico o mecanicista constituye una función biológica, globalmente, la función explica la estructura y no a la inversa, a pesar de que en algunos casos particulares, el orden en que se determinan los conceptos participantes en la explicación no coincide con el orden de la explicación. Para defender esta tesis, adoptaremos una concepción mínima de explicación basada en la idea de subsunción (...) ampliativa del estructuralismo e ilustraremos las diferencias entre el orden de la explicación y el orden de determinación de los conceptos mediante un estudio de caso tomado de la afasiología moderna. (shrink)

Due to an unfortunate turn of events, the family name of the first author was erroneously published as ‘RoffÕ’ in the original publication. The correct representation of the first author’s family name is listed above and below.

In a recent book, McShea and Brandon argue that the observed diversity and complexity of life are explainable by a principle they call the “zero-force evolutionary law” or “ZFEL”. Although this principle would be implicit in many explanations given by biologists, it would have never been made explicit. Assuming that this idea is interesting, and that the authors are right, we will discuss the metatheoretical way in which they present said principle, as being a part of probability theory. This allows (...) the authors to claim that probability theory provides the reductive basis for all evolutionary biology. We will defend, in accordance with them, that ZFEL is not a solely biological principle, but not because it is a part of probability theory, but rather because it is a specific version of the principle of common cause. (shrink)

En este ambicioso libro, el biólogo Daniel W. McShea y el filósofo de la biología Robert N. Brandon desafían las explicaciones explícitas encontradas en la litera-tura acerca del origen de la diversidad y la complejidad en los seres vivos. Estas explicaciones recurren en su mayoría a la acción de la selección natural, como ser, a la selección diversificadora/disruptiva, a la selección de niveles superiores favoreciendo a especies/clados con mayor propensión a la especiación, o a las ventajas de una mayor división (...) del trabajo, entre otras alternativas (p. 1). Si bien estas explicaciones pueden ser correctas, no constituirían toda la historia, según los autores, pues habría una tendencia de fondo no reconocida en la literatura (pero invocada en las explicaciones de casos concretos) hacia un aumento de la diversidad y la complejidad. Esta tendencia surgiría simplemente de que las variaciones azarosas, cuando se heredan, se acumulan en diferentes direcciones en diferentes poblaciones, con el resultado de que la diversidad se incrementa. Para expresar esta tendencia, los autores proponen una ley, que denominan ZFEL (por zero-force evolutionary law) y que formulan de la siguiente manera: “En cualquier sistema evolutivo en el que hay variación azarosa y he-rencia, en ausencia de fuerzas y constricciones, la diversidad y la complejidad tenderán a aumentar” (p. 4). (shrink)