What you don’t know can’t hurt you: realism and the unconceived

Two of the most potent challenges faced by scientific realism are the underdetermination of theories by data, and the pessimistic induction based on theories previously held to be true, but subsequently acknowledged as false. Recently, Stanford (2006, Exceeding our grasp: Science, history, and the problem of unconceived alternatives. Oxford: Oxford University Press) has formulated what he calls the problem of unconceived alternatives: a version of the underdetermination thesis combined with a historical argument of the same form as the pessimistic induction. In this paper, I contend that while Stanford does present a novel antirealist argument, a successful response to the pessimistic induction would likewise defuse the problem of unconceived alternatives, and that a more selective and sophisticated realism than that which he allows is arguably immune to both concerns.

The Search for Adam Revisited: Evolution,Biblical Literalism,and the Question of Human Uniqueness

Abstract

This article questions the adequacy of the philosophical category of realism in characterizing Rheticus' endorsement of Copernicus' astronomy. Rheticus and Osiander agree that the human intellect is restricted in its aspirations to truth, resulting in a condition of “causal ignorance” regarding the celestial phenomena on Rheticus' part. Copernicus' pupil advances trust in the most true hypothesis of the motion of the earth without postulating its absolute truth. Causal knowledge waits after Resurrection. In line with Luther's comment on Genesis 1:14, Rheticus ascribes a theological meaningfulness to the pursuit of mathematics, alerting the astronomer to his immortal soul and divine creation.     

A selectionist explanation for the success and failures of science

I argue that van Fraassen’s selectionist explanation for the success of science is superior to the realists’ explanation. Whereas realists argue that our current theories are successful because they accurately reflect the structure of the world, the selectionist claims that our current theories are successful because unsuccessful theories have been eliminated. I argue that, unlike the explanation proposed by the realist, the selectionist explanation can also account for the failures of once successful theories and the fact that sometimes two competing theories are both equally successful.

Bayes and blickets: effects of knowledge on causal induction in children and adults

People are adept at inferring novel causal relations, even from only a few observations. Prior knowledge about the probability of encountering causal relations of various types and the nature of the mechanisms relating causes and effects plays a crucial role in these inferences. We test a formal account of how this knowledge can be used and acquired, based on analyzing causal induction as Bayesian inference. Five studies explored the predictions of this account with adults and 4-year-olds, using tasks in which participants learned about the causal properties of a set of objects. The studies varied the two factors that our Bayesian approach predicted should be relevant to causal induction: the prior probability with which causal relations exist, and the assumption of a deterministic or a probabilistic relation between cause and effect. Adults' judgments (Experiments 1, 2, and 4) were in close correspondence with the quantitative predictions of the model, and children's judgments (Experiments 3 and 5) agreed qualitatively with this account.     

Visual analysis of single-case time series: Effects of variability, serial dependence, and magnitude of intervention effects

Visual analysis is the dominant method of analysis for single-case time series. The literature assumes that visual analysts will be conservative judges. We show that previous research into visual analysis has not adequately examined false alarm and miss rates or the effect of serial dependence. In order to measure false alarm and miss rates while varying serial dependence, amount of random variability, and effect size, 37 students undertaking a postgraduate course in single-case design and analysis were required to assess the presence of an intervention effect in each of 27 AB charts constructed using a first-order autoregressive model. Three levels of effect size and three levels of variability, representative of values found in published charts, were combined with autocorrelation coefficients of 0, 0.3 and 0.6 in a factorial design. False alarm rates were surprisingly high (16% to 84%). Positive autocorrelation and increased random variation both significantly increased the false alarm rates and interacted in a nonlinear fashion. Miss rates were relatively low (0% to 22%) and were not significantly affected by the design parameters. Thus, visual analysts were not conservative, and serial dependence did influence judgment.     

Sensitivity,Induction, and Miracles

Sosa, Pritchard, and Vogel have all argued that there are cases in which one knows something inductively but does not believe it sensitively, and that sensitivity therefore cannot be necessary for knowledge. I defend sensitivity by showing that inductive knowledge is sensitive.     

A Note on Prototypes,Convexity and Fuzzy Sets

The work on prototypes in ontologies pioneered by Rosch [10] and elaborated by Lakoff [8] and Freund [3] is related to vagueness in the sense that the more remote an instance is from a prototype the fewer people agree that it is an example of that prototype. An intuitive example is the prototypical “mother”, and it is observed that more specific instances like ”single mother”, “adoptive mother”, “surrogate mother”, etc., are less and less likely to be classified as “mothers” by experimental subjects. From a different direction Gärdenfors [4] provided a persuasive account of natural predicates to resolve paradoxes of induction like Goodman’s “Grue” predicate [5]. Gärdenfors proposed that “quality dimensions” arising from human cognition and perception impose topologies on concepts such that the ones that appear “natural” to us are convex in these topologies. We show that these two cognitive principles — prototypes and predicate convexity — are equivalent to unimodal (convex) fuzzy characteristic functions for sets. Then we examine the case when the fuzzy set characteristic function is not convex, in particular when it is multi-modal. We argue that this is an indication that the fuzzy concept should really be regarded as a super concept in which the decomposed components are subconcepts in an ontological taxonomy.     

术前人文关怀对肺癌手术患者全麻诱导心理和生理的影响

为探讨术前进行人文关怀式沟通和健康教育对肺癌手术患者全麻诱导后心理和生理的影响,将83例非同期别的肺癌手术患者（均采用全身麻醉,双腔管气管插管辅助通气）分成两组。观察组进行人文关怀式沟通,对照组采用普通沟通。判定方法采用焦虑自评量表（SAS）,根据焦虑评分反映两组患者入院即刻及手术前的心理变化情况,监测全麻诱导即刻与全麻诱导气管插管后5min患者平均动脉压（MBP）的波动、心率（HR）的变化,用两个时间段两个变量的差值来反映两组患者全麻诱导期发生心理和生理反应的情况。结果显示,两组患者入院即刻焦虑差异无统计学意义（P〉0．05）;手术前SAS评分两组患者较入院即刻降低（P〈0．05）,并且观察组与对照组相比下降更明显（P〈0．01）;观察组患者MBP波动无统计学意义（P〉0．05）、HR波动有统计学意义（P〈0．05）。因此,证实人文关怀式沟通和健康教育能够减轻肺癌患者在心理和生理两个方面对麻醉和手术产生的不良反应。