How do people make deductions? The orthodox view in psychology is that they use formal rules of inference like those of a “natural deduction” system.Deductionargues that their logical competence depends, not on formal rules, but on mental models. They construct models of the situation described by the premises, using their linguistic knowledge and their general knowledge. They try to formulate a conclusion based on these models that maintains semantic information, that expresses it parsimoniously, and that makes explicit something not directly (...) stated by any premise. They then test the validity of the conclusion by searching for alternative models that might refute the conclusion. The theory also resolves long-standing puzzles about reasoning, including how nonmonotonic reasoning occurs in daily life. The book reports experiments on all the main domains of deduction, including inferences based on prepositional connectives such as “if” and “or,” inferences based on relations such as “in the same place as,” inferences based on quantifiers such as “none,” “any,” and “only,” and metalogical inferences based on assertions about the true and the false. Where the two theories make opposite predictions, the results confirm the model theory and run counter to the formal rule theories. Without exception, all of the experiments corroborate the two main predictions of the model theory: inferences requiring only one model are easier than those requiring multiple models, and erroneous conclusions are usually the result of constructing only one of the possible models of the premises. (shrink)

I offer an examination of a core element in the reflectiveness of Heraclitus’ thought, namely, his rebuke of polymathy . In doing so, I provide a response to a recent claim that Heraclitus should not be considered to be a philosopher, by attending to his paradigmatically philosophical traits. Regarding Heraclitus’ attitude to that naïve form of ‘wisdom’, i.e., polymathy, I argue that he does not advise avoiding experience of many things, rather, he advises rejecting experience of things as merely many (...) independent things in their manifoldness , and, instead, to understand their unity and thereby to unify our knowledge of them. (shrink)

This page is dedicated to an analysis of the first section of Parmenides' Poem, the Way of Truth, with a selection of critical judgments by the most important commentators and critics. In the Annotated Bibliography I list the main critical editions (from the first printed edition of 1573 to present days) and the translations in English, French, German, Italian and Spanish, with a selection of studies on Parmenides; in future, a section will be dedicated to an examination of some critical (...) variants of the Greek text, with particular attention to corrections to the Diels-Kranz (abbreviated DK) edition of the Fragmente der Vorsokratiker. The fragments of Parmenides' Poem are cited according to Diels-Kranz numbering system as adopted in the 6th edition, Berlin 1952; the Poem is divided into three parts: the Proem fr. I, 1-32; the Way of Truth (Alethéia) from fr. II to VIII, 49, and the Way of Mortal Opinion (Doxa) fr. VIII, 50 to XIX, 3. (shrink)