First, we describe a psychological experiment in which the participants were asked to determine whether sentences of first-order logic were true or false in finite graphs. Second, we define two proof systems for reasoning about truth and falsity in first-order logic. These proof systems feature explicit models of cognitive resources such as declarative memory, procedural memory, working memory, and sensory memory. Third, we describe a computer program that is used to find the smallest proofs in the aforementioned proof systems when (...) capacity limits are put on the cognitive resources. Finally, we investigate the correlation between a number of mathematical complexity measures defined on graphs and sentences and some psychological complexity measures that were recorded in the experiment. (shrink)

In this essay, I first discuss the conditions set by theorists of democratic deliberation on proper deliberation. These conditions call for reasoned decisions from mutually acceptable premises. Next, I present the ideal of critical thinking that should guide the citizen in this deliberation. I then examine the empirical literature on human reasoning. Some research results in the empirical literature paint a bleak picture of human rationality: we fall victim to heuristics and biases, persevere in our beliefs in the face of (...) contrary evidence, and justify our moral judgments by post hoc-reasoning. In addition, the deliberating groups have problems of their own. The groups may, for example, amplify errors or fall victim to information cascades. Though these epistemically detrimental processes can be overcome, they do present a challenge to our rationality. The essay concludes by arguing that the empirical evidence in fact supports an internalistic approach to group deliberation, a claim challenged by Solomon. (shrink)

In his enormously influentialThe Modularity of Mind, Jerry Fodor (1983) proposed that the mind was divided into input modules and central processes. Much subsequent research focused on the modules and whether processes like speech perception or spatial vision are truly modular. Much less attention has been given to Fodor's writing on the central processes, what would today be called higher‐level cognition. In “Fodor's First Law of the Nonexistence of Cognitive Science,” he argued that central processes are “bad candidates for scientific (...) study” and would resist attempts at empirical analysis. This essay evaluates his argument for this remarkable claim, concluding that although central processes may well be “messier” than input modules, this does not mean that they cannot be studied and understood. The article briefly reviews the scientific progress made in understanding central processes in the 35 years since the book was published, showing that Fodor's prediction is clearly falsified by massive advances in topics like decision making and analogy. The essay concludes that Fodor's Law was not based on a clear argument for why the complexities of central systems could not be studied but was likely based on intuitions and preferences that were common in psychology at the time. (shrink)