Inductive reasoning about causally transmitted properties

Different intuitive theories constrain and guide inferences in different contexts. Formalizing simple intuitive theories as probabilistic processes operating over structured representations, we present a new computational model of category-based induction about causally transmitted properties. A first experiment demonstrates undergraduates’ context-sensitive use of taxonomic and food web knowledge to guide reasoning about causal transmission and shows good qualitative agreement between model predictions and human inferences. A second experiment demonstrates strong quantitative and qualitative fits to inferences about a more complex artificial food web. A third experiment investigates human reasoning about complex novel food webs where species have known taxonomic relations. Results demonstrate a double-dissociation between the predictions of our causal model and a related taxonomic model [Kemp, C., & Tenenbaum, J. B. (2003). Learning domain structures. In Proceedings of the 25th annual conference of the cognitive science society]: the causal model predicts human inferences about diseases but not genes, while the taxonomic model predicts human inferences about genes but not diseases. We contrast our framework with previous models of category-based induction and previous formal instantiations of intuitive theories, and outline challenges in developing a complete model of context-sensitive reasoning.     

The spacing effect in children's memory and category induction

The spacing effect describes the robust phenomenon whereby memory is enhanced when learning events are distributed, instead of being presented in succession. We investigated the effect of spacing on children's memory and category induction. Three-year-old children were presented with two tasks, a memory task and a category induction task. In the memory task, identical instances of an object were presented and then tested in a multiple choice test. In the category induction task, different instances of a category were presented and tested in a multiple choice test. In both tasks, presenting the instances in a spaced sequence resulted in more learning than presenting the instances in a massed sequence, despite the difficulty created by the spaced sequence. The spaced sequence increased the difficulty of the task by allowing children time to forget the previous instance during the spaced interval.     

Common control by compound samples in conditional discriminations

We tested whether teaching control by single stimulus samples in conditional discriminations would result in common control of two-stimuli compound samples, and vice versa. In Experiment 1, 5 participants were first taught four single-sample conditional discriminations. The first conditional discrimination was as follows: given sample stimulus P1, select comparison stimulus A1 and not A2; given sample P2 select comparison A2 and not A1. The second conditional discrimination was as follows: given sample P1 select comparison B1 and not B2; given sample P2 select B2 and not B1. Different sample stimuli (Q1 and Q2) were used in the third and fourth conditional discriminations. Moreover, A1 and B1 were presented together as comparisons, such that, if Q1 was presented as the sample, A1 was correct and B1 was incorrect; and if Q2 was presented as the sample, B1 was correct and A1 was incorrect. A2 and B2 were also presented as comparisons. When Q1 was presented, A2 was correct and when Q2 was presented B2 was correct. After training with these four single stimulus sample discriminations, participants were tested with compound PQ samples presented with A1, A2, B1, and B2 as comparisons. If common control were established by the PQ stimuli, a participant would select A1 when P1Q1 was presented, A2 when P2Q1 was presented, B1 when P1Q2 was presented, and B2 when P2Q2 was presented. Such common control by PQ samples occurred in 4 of 5 participants. In Experiment 2, 4 participants were given reverse training. They were first taught to select the A1, A2, B1, and B2 stimuli in response to the appropriate PQ combinations and then probed on the single stimulus sample discriminations. All 4 participants were successful on this probe. Experiments 3 and 4 investigated the effects of teaching additional conditional discriminations with novel stimuli on subsequent transfer from the single-sample discriminations to performance on the compound-sample conditional discrimination.     

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.

儿童对观察者预期造成的模糊刺激解释多样性的理解

研究考察6~8岁儿童在由观察者预期造成的对模糊信息有多样解释上的理解.操纵影响观察者预期的因素,包括知觉经验、知识水平、先前经历和偏见,要求儿童预测观察者对局限视野图形或两可动作信息的解释.结果表明,6岁儿童仅对观察者偏见影响其对行动者行为的解释拥有部分理解,他们还不能理解知觉经验和知识水平会影响观察者对视觉刺激的解释,以及先前经历会影响观察者对行动者行为的解释.7岁儿童除了知识水平外,其它三方面的理解都已发展起来.8岁儿童可以理解多种观察者预期造成的解释差异,解释性心理理论比较稳定,但离完全成熟的理解还有一段距离.     

辅助生殖技术与女性生殖系统肿瘤的关系及其辩证思考

辅助生殖技术给不孕患者带来了希望,为肿瘤患者保留了生育能力,另一方面也可能导致女性生殖系统肿瘤和一系列伦理学问题。因此,用哲学的观点客观地看待辅助生殖技术与女性生殖系统肿瘤发生风险之间的关系,将有助于临床医生进一步提高辅助生殖技术安全性的认识,选择最佳的促排卵方案。     

知觉和概念信息对3岁儿童归纳推理的影响

采用经典的三角归纳范式(Gelman & Markman,1986)研究了3岁儿童的归纳推理及其影响因素。采用龙长权、路晓英、李红和范籍丹(2008)的研究中相同的实验材料和程序,测试了3岁儿童的归纳,结果表明3岁儿童基于知觉相似和基于概念类别之间的差异不显著(实验一)。增加了与靶刺激在知觉上不相似且不属于同一类别的分心刺激之后,3岁儿童能够忽略分心刺激,表明3岁儿童不是在随机猜测(实验二)。分类实验表明3岁儿童能够根据概念关系对实验材料中的项目进行分类,表明3岁儿童具有关于实验项目的概念知识(实验三)。提高概念比较刺激与靶刺激的知觉相似程度,降低知觉比较刺激和概念比较刺激与靶刺激在知觉相似上的冲突程度之后,3岁儿童基于知觉相似和基于概念类别选择之间的差异仍不显著,表明抑制控制不是导致儿童在实验一中表现出基于知觉相似和基于概念类别之间差异不显著的原因(实验四)。降低概念比较刺激与靶刺激之间的类别等级结构,使概念比较刺激与靶刺激属于相同的基本水平类别时,3岁儿童能够主要基于概念类别进行归纳(实验五)。增加经典三角测试的前提的数量,3岁儿童也能主要基于概念类别进行归纳(实验六)。这些研究表明,3岁儿童在一定条件下能够基于概念类别进行归纳,多个因素能够影响3岁儿童在三角测试中的表现。     

Resisting Explanation

Although explanation is widely regarded as an important concept in the study of rational inquiry, it remains largely unexplored outside the philosophy of science. This, I believe, is not due to oversight as much as to institutional resistance. In analytic philosophy it is basic that epistemic rationality is a function of justification and that justification is a function of argument. Explanation, however, is not argument nor is belief justification its function. I argue here that the task of incorporating explanation into the theory of rational inquiry poses a serious challenge to our basic concept of epistemic rationality as well as the a priori method of inquiry that still lies at the heart of analytic philosophy. Specifically, it pushes us toward a much stronger form of naturalism than is generally thought necessary, one in which argument and explanation are recognized as distinct and equally fundamental cognitive processes whose dynamic relationship is one of the central issues in the theory of rationality.     

Farewell to certitude: Einstein's novelty on Induction and Deduction, Fallibilism

In the late 19th century great changes in theories of light and electricity were in direct conflict with certitude, the view that scientific knowledge is infallible. What is, then, the epistemic status of scientific theory? To resolve this issue Duhem and Poincaré proposed images of fallible knowledge, Instrumentalism and Conventionalism, respectively. Only in 1919–1922, after Einstein's relativity was published, he offered arguments to support Fallibilism, the view that certainty cannot be achieved in science. Though Einstein did not consider Duhem's Instrumentalism, he argued against Poincaré's Conventionalism. Hitherto, Einstein's Fallibilism, as presented at first in a rarely known essay of 1919, was left in the dark. Recently, Howard obscured its meaning. Einstein's essay was never translated into English. In my paper I provide its translation and attempt to shed light on Einstein's view and its context; I also direct attention to Einstein's images of philosophical opportunism in scientific practice.     

Unconscious odour conditioning 25 years later: Revisiting and extending ‘Kirk-Smith, Van Toller and Dodd’

The pioneering work by Kirk-Smith, Van Toller, and Dodd [Kirk-Smith, M. D., Van Toller, C., & Dodd, G. H. (1983). Unconscious odour conditioning in human subjects. Biological Psychology, 17, 221–231], established that an unnoticed odorant paired with an emotionally meaningful task can influence mood and attitudes when the odorant alone is re-encountered subsequently. This study was particularly important in highlighting unconscious odour learning processes as they may happen in everyday life. However, it was severely criticized by Black and Smith [Black, S. L., & Smith, D. G. (1994). Has odor conditioning been demonstrated? A critique of “Unconscious odour conditioning in human subjects”. Biological Psychology, 37, 265–267] on methodological grounds. In the present paper, we replicated and extended Kirk-Smith et al.’s investigation taking into account Black and Smith’s criticisms and carrying out additional controls to improve the validity of the study. The results confirm the initial findings of Kirk-Smith and colleagues by demonstrating the effectiveness of olfactory stimuli in inducing conditioned hedonic reactions even when presented below the level of awareness.