We provide a new link between deductive and probabilistic reasoning fallacies. Illusory inferences from disjunction are a broad class of deductive fallacies traditionally explained by recourse to a matching procedure that looks for content overlap between premises. In two behavioral experiments, we show that this phenomenon is instead sensitive to real-world causal dependencies and not to exact content overlap. A group of participants rated the strength of the causal dependence between pairs of sentences. This measure is a near perfect predictor of fallacious reasoning by an independent group of participants in illusory inference tasks with the same materials. In light of these results, we argue that all extant accounts of these deductive fallacies require non-trivial adjustments. Crucially, these novel indirect illusory inferences from disjunction bear a structural similarity to seemingly unrelated probabilistic reasoning problems, in particular the conjunction fallacy from the heuristics and biases literature. This structural connection was entirely obscure in previous work on these deductive problems, due to the theoretical and empirical focus on content overlap. We argue that this structural parallelism provides arguments against the need for rich descriptions and individuating information in the conjunction fallacy, and we outline a unified theory of deductive illusory inferences from disjunction and the conjunction fallacy, in terms of Bayesian confirmation theory.

我们提供了演绎推理谬误和概率推理谬误之间的新联系。来自析取的虚幻推理是一大类演绎谬误，传统上通过求助于寻找前提之间内容重叠的匹配程序来解释。在两个行为实验中，我们表明这种现象对现实世界的因果依赖敏感，而不是对确切的内容重叠敏感。一组参与者对成对句子之间的因果依赖强度进行了评估。该度量几乎完美地预测了一组独立的参与者在使用相同材料进行虚幻推理任务时的错误推理。鉴于这些结果，我们认为对这些演绎谬误的所有现存解释都需要进行非平凡的调整。至关重要的是，这些新颖的间接来自析取的虚幻推理与看似无关的概率推理问题具有结构相似性，尤其是启发式和偏见文献中的合取谬误。由于理论和经验对内容重叠的关注，这种结构联系在之前关于这些演绎问题的工作中完全模糊。我们认为，这种结构并行性提供了反对在合取谬误中需要丰富的描述和个体化信息的论据，并且根据贝叶斯确认理论，我们概述了从析取和合取谬误中得出的演绎幻觉推理的统一理论。