Is there some general reason to expect organisms that have beliefs to have false beliefs? And after you observe that an organism occasionally occupies a given neural state that you think encodes a perceptual belief, how do you evaluate hypotheses about the semantic content that that state has, where some of those hypotheses attribute beliefs that are sometimes false while others attribute beliefs that are always true? To address the first of these questions, we discuss evolution by natural selection and (...) show how organisms that are risk-prone in the beliefs they form can be fitter than organisms that are risk-free. To address the second question, we discuss a problem that is widely recognized in statistics – the problem of over-fitting – and one influential device for addressing that problem, the Akaike Information Criterion (AIC). We then use AIC to solve epistemological versions of the disjunction and distality problems, which are two key problems concerning what it is for a belief state to have one semantic content rather than another. (shrink)

We conceptualize observation selection effects (OSEs) by considering how a shift from one process of observation to another affects discrimination-conduciveness, by which we mean the degree to which possible observations discriminate between hypotheses, given the observation process at work. OSEs in this sense come in degrees and are causal, where the cause is the shift in process, and the effect is a change in degree of discrimination-conduciveness. We contrast our understanding of OSEs with others that have appeared in the literature. (...) After describing conditions of adequacy that an acceptable measure of degree of discrimination-conduciveness must satisfy, we use those conditions of adequacy to evaluate several possible measures. We also discuss how the effect of shifting from one observation process to another might be measured. We apply our framework to several examples, including the ravens paradox and the phenomenon of publication bias. (shrink)

We argue in Roche and Sober (2013) that explanatoriness is evidentially irrelevant in that Pr(H | O&EXPL) = Pr(H | O), where H is a hypothesis, O is an observation, and EXPL is the proposition that if H and O were true, then H would explain O. This is a “screening-off” thesis. Here we clarify that thesis, reply to criticisms advanced by Lange (2017), consider alternative formulations of Inference to the Best Explanation, discuss a strengthened screening-off thesis, and consider how (...) it bears on the claim that unification is evidentially relevant. (shrink)

In their 2010 book, Biology’s First Law, D. McShea and R. Brandon present a principle that they call ‘‘ZFEL,’’ the zero force evolutionary law. ZFEL says (roughly) that when there are no evolutionary forces acting on a population, the population’s complexity (i.e., how diverse its member organisms are) will increase. Here we develop criticisms of ZFEL and describe a different law of evolution; it says that diversity and complexity do not change when there are no evolutionary causes.

We argue elsewhere that explanatoriness is evidentially irrelevant . Let H be some hypothesis, O some observation, and E the proposition that H would explain O if H and O were true. Then O screens-off E from H: Pr = Pr. This thesis, hereafter “SOT” , is defended by appeal to a representative case. The case concerns smoking and lung cancer. McCain and Poston grant that SOT holds in cases, like our case concerning smoking and lung cancer, that involve frequency (...) data. However, McCain and Poston contend that there is a wider sense of evidential relevance—wider than the sense at play in SOT—on which explanatoriness is evidentially relevant even in cases involving frequency data. This is their main point, but they also contend that SOT does not hold in certain cases not involving frequency data. We reply to each of these points and conclude with some general remarks on screening-off as a test of evidential relevance. (shrink)

We argued that explanatoriness is evidentially irrelevant in the following sense: Let H be a hypothesis, O an observation, and E the proposition that H would explain O if H and O were true. Then our claim is that Pr = Pr. We defended this screening-off thesis by discussing an example concerning smoking and cancer. Climenhaga argues that SOT is mistaken because it delivers the wrong verdict about a slightly different smoking-and-cancer case. He also considers a variant of SOT, called (...) “SOT*”, and contends that it too gives the wrong result. We here reply to Climenhaga’s arguments and suggest that SOT provides a criticism of the widely held theory of inference called “inference to the best explanation”. (shrink)

Los filósofos han tendido a discutir el esencialismo como si fuera una doctrina global, una filosofía que, por alguna razón uniforme, debiera ser adoptada por todas las ciencias o por ninguna. Popper (1972) ha adoptado una postura global negativa, porque ve al esencialismo como un obstáculo fundamental para la racionalidad científica. También Quine (1953b, 1960), por una combinación de motivos semánticos y epistemológicos, quiere desterrar el esencialismo de la totalidad del discurso científico. Sin embargo, en fechas más recientes, Putnam (1975) (...) y Kripke (1972) han propugnado doctrinas esencialistas y han afirmado que es tarea de cada ciencia investigar las propiedades esenciales de sus clases naturales constitutivas. (shrink)

Do traits evolve because they are good for the group, or do they evolve because they are good for the individual organisms that have them? The question is whether groups, rather than individual organisms, are ever “units of selection.” My exposition begins with the 1960’s, when the idea that traits evolve because they are good for the group was criticized, not just for being factually mistaken, but for embodying a kind of confused thinking that is fundamentally at odds with the (...) logic that Darwin’s theory requires. A counter-movement has arisen since the 1960’s, called multi-level selection theory, according to which selection acts at multiple levels, including the level of the group. After discussing the 1960’s attack on group selection and the concept’s subsequent revival, I examine Darwin’s views on the subject. I discuss what Darwin says about four examples: human morality, the barbed stinger of the honeybee, neuter workers in species of social insect, and the sterility of many interspecies hybrids. I argue that Darwin defended hypotheses of group selection in the first three problems, but rejected it in the fourth. I also discuss Darwin’s general views about the role of group selection in evolution. (shrink)