The step to rationality: the efficacy of thought experiments in science, ethics, and free will

Examples from Archimedes, Galileo, Newton, Einstein, and others suggest that fundamental laws of physics were—or, at least, could have been—discovered by experiments performed not in the physical world but only in the mind. Although problematic for a strict empiricist, the evolutionary emergence in humans of deeply internalized implicit knowledge of abstract principles of transformation and symmetry may have been crucial for humankind's step to rationality—including the discovery of universal principles of mathematics, physics, ethics, and an account of free will that is compatible with determinism.     

On being stuck in time

It is sometimes claimed that non-human animals (and perhaps also young children) live their lives entirely in the present and are cognitively ‘stuck in time’. Adult humans, by contrast, are said to be able to engage in ‘mental time travel’. One possible way of making sense of this distinction is in terms of the idea that animals and young children cannot engage in tensed thought, which might seem a preposterous idea in the light of certain findings in comparative and developmental psychology. I try to make this idea less preposterous by looking into some of the cognitive requirements for tensed thought. In particular, I suggest that tensed thought requires a specific form of causal understanding, which animals and young children may not possess.

汉字阅读的语义神经回路及其与语音回路的协作机制

从神经网络的角度研究词汇阅读的大脑神经机制, 需要揭示语义和语音神经回路的动态协作机制, 而语义加工神经回路是探讨该问题的一个亟待解决的瓶颈问题。利用汉字表义的独特性, 以形旁语义作用的神经机制为切入点, 计划开展的4个fMRI实验拟探讨汉字阅读的语义神经回路及其与语音回路的动态协作机制。实验1利用多参数相关分析技术, 识别与汉字语义和语音属性相关的功能脑区; 实验2和实验3集中考察形旁语义加工的大脑神经机制, 深入探讨形旁语义作用的实质, 揭示汉字阅读中语义加工的神经回路; 实验4通过建构汉字阅读的动态因果模型, 考察在刺激驱动和任务调节下, 阅读相关脑区联结模式的动态变化, 阐明语义和语音神经回路的相互协作机制。研究结果将从跨语言的角度, 阐明阅读神经网络的内部动态机制, 为联结主义理论提供神经生理方面的直接证据; 并为基于脑科学的教育教学和阅读障碍矫治等实践应用提供理论依据。     

Systematicity redux

One of the main challenges that Jerry Fodor and Zenon Pylyshyn (Cognition 28:3–71, 1988) posed for any connectionist theory of cognitive architecture is to explain the systematicity of thought without implementing a Language of Thought (LOT) architecture. The systematicity challenge presents a dilemma: if connectionism cannot explain the systematicity of thought, then it fails to offer an adequate theory of cognitive architecture; and if it explains the systematicity of thought by implementing a LOT architecture, then it fails to offer an alternative to the LOT hypothesis. Given that thought is systematic, connectionism can offer an adequate alternative to the LOT hypothesis only if it can meet the challenge. Although some critics tried to meet the challenge, others argued that it need not be met since thought is not in fact systematic; and some claimed not to even understand the claim that thought is systematic. I do not here examine attempts to answer the challenge. Instead, I defend the challenge itself by explicating the notion of systematicity in a way that I hope makes clear that thought is indeed systematic, and so that to offer an adequate alternative to the LOT hypothesis, connectionism must meet the challenge.     

Mental Health Clinicians' Beliefs About the Biological, Psychological, and Environmental Bases of Mental Disorders

The current experiments examine mental health clinicians' beliefs about biological, psychological, and environmental bases of the DSM-IV-TR mental disorders and the consequences of those causal beliefs for judging treatment effectiveness. Study 1 found a large negative correlation between clinicians' beliefs about biological bases and environmental/psychological bases, suggesting that clinicians conceptualize mental disorders along a single continuum spanning from highly biological disorders (e.g., autistic disorder) to highly nonbiological disorders (e.g., adjustment disorders). Study 2 replicated this finding by having clinicians list what they thought were the specific causes of nine familiar mental disorders and rate their bio–psycho–environmental bases. Study 3 further found that clinicians believe medication to be more effective for biologically based mental disorders and psychotherapy to be more effective for psychosocially based mental disorders. These results demonstrate that even expert mental health clinicians make strong distinctions between psychological and biological phenomena.     

Simplicity and probability in causal explanation

What makes some explanations better than others? This paper explores the roles of simplicity and probability in evaluating competing causal explanations. Four experiments investigate the hypothesis that simpler explanations are judged both better and more likely to be true. In all experiments, simplicity is quantified as the number of causes invoked in an explanation, with fewer causes corresponding to a simpler explanation. Experiment 1 confirms that all else being equal, both simpler and more probable explanations are preferred. Experiments 2 and 3 examine how explanations are evaluated when simplicity and probability compete. The data suggest that simpler explanations are assigned a higher prior probability, with the consequence that disproportionate probabilistic evidence is required before a complex explanation will be favored over a simpler alternative. Moreover, committing to a simple but unlikely explanation can lead to systematic overestimation of the prevalence of the cause invoked in the simple explanation. Finally, Experiment 4 finds that the preference for simpler explanations can be overcome when probability information unambiguously supports a complex explanation over a simpler alternative. Collectively, these findings suggest that simplicity is used as a basis for evaluating explanations and for assigning prior probabilities when unambiguous probability information is absent. More broadly, evaluating explanations may operate as a mechanism for generating estimates of subjective probability.     

Baumann on the Monty Hall problem and single-case probabilities

Peter Baumann uses the Monty Hall game to demonstrate that probabilities cannot be meaningfully applied to individual games. Baumann draws from this first conclusion a second: in a single game, it is not necessarily rational to switch from the door that I have initially chosen to the door that Monty Hall did not open. After challenging Baumann’s particular arguments for these conclusions, I argue that there is a deeper problem with his position: it rests on the false assumption that what justifies the switching strategy is its leading me to win a greater percentage of the time. In fact, what justifies the switching strategy is not any statistical result over the long run but rather the “causal structure” intrinsic to each individual game itself. Finally, I argue that an argument by Hilary Putnam will not help to save Baumann’s second conclusion above. See Moser and Mulder (1994, pp. 115–116, 118).     

From mere coincidences to meaningful discoveries

People's reactions to coincidences are often cited as an illustration of the irrationality of human reasoning about chance. We argue that coincidences may be better understood in terms of rational statistical inference, based on their functional role in processes of causal discovery and theory revision. We present a formal definition of coincidences in the context of a Bayesian framework for causal induction: a coincidence is an event that provides support for an alternative to a currently favored causal theory, but not necessarily enough support to accept that alternative in light of its low prior probability. We test the qualitative and quantitative predictions of this account through a series of experiments that examine the transition from coincidence to evidence, the correspondence between the strength of coincidences and the statistical support for causal structure, and the relationship between causes and coincidences. Our results indicate that people can accurately assess the strength of coincidences, suggesting that irrational conclusions drawn from coincidences are the consequence of overestimation of the plausibility of novel causal forces. We discuss the implications of our account for understanding the role of coincidences in theory change.     

Terror salience and punishment: Does terror salience induce threat to social order?

In recent times, international terrorism has become one of the most serious concerns of the modern Western world. As a consequence, the risk and fear of terrorism is more salient in people’s minds (i.e. terror salience), which is supposed to affect behavioral responses in our society. The present research suggests that increased punishment of violations of criminal laws is one societal reaction to increased terror salience. It was consistently shown that increased terror salience, induced by either varying the temporal distance from the London terrorist attacks of July 7, 2005 (Study 1), by vignettes in the form of newspaper articles manipulating the expected terror risk (Study 2), or by pictures of recent terrorist attacks (Studies 3 and 4), significantly increased the punishment assigned to a violation of criminal laws that was completely unrelated to terror (i.e. car theft and rape). Finally, Study 4 revealed that (a) the effect of terror salience on punishment is indeed due to increased perception of threat to social order and (b) that this effect cannot be explained by the general negative nature of the stimulus material employed in this study.     

The Logical Structure of Classical Genetics

We present a reconstruction of so-called classical, formal or Mendelian genetics using a notation which we believe is more legible than that of earlier accounts, and lends itself easily to computer implementation, for instance in PROLOG. By drawing from, and emending, earlier work of Balzer and Dawe (1986,1997), the present account presents the three most important lines of development of classical genetics: the so-called Mendel's laws, linkage genetics and gene mapping, in the form of a theory-net. This shows that the set theoretic representation format used in the structuralist approach to the philosophy of science also applies to the domain of genetic theories. There construction is intended to lend more clarity to theme thodological, philosophical and didactical discussions of the foundations of genetics, and on the other hand to defend a formally, logically minded view of theories which seems to have become contested through the work of Feyerabend, Kuhn and Kitcher. This revised version was published online in August 2006 with corrections to the Cover Date.