This volume examines the entire logical and philosophical production of Nikolai A. Vasil’ev, studying his life and activities as a historian and man of letters. Readers will gain a comprehensive understanding of this influential Russian logician, philosopher, psychologist, and poet. The author frames Vasil’ev’s work within its historical and cultural context. He takes into consideration both the situation of logic in Russia and the state of logic in Western Europe, from the end of the 19th century to the beginning of (...) the 20th. Following this, the book considers the attempts to develop non-Aristotelian logics or ideas that present affinities with imaginary logic. It then looks at the contribution of traditional logic in elaborating non-classical ideas. This logic allows the author to deal with incomplete objects just as imaginary logic does with contradictory ones. Both logics are objects of interesting analysis by modern researchers. (shrink)

At APr 2.4 57a36–13, Aristotle presents a notorious reductio argument in which he derives the claim ‘If B is not large, B is large’ and calls that result impossible. Aristotle is thus committed to some form of connexivity and this paper argues that his commitment is to a strong form of connexivity which excludes even cases in which ‘B is large’ is necessary. It is further argued that Aristotle’s view of connexivity is best understood as arising from his analysis of (...) affirmation and negation in terms of combination and separation: a proposition that separates two terms cannot entail a proposition that combines the same two terms. In order to motivate this account of connexivity, this paper interprets Aristotle as emphasising the predicative structure, especially the copulae, of the argument’s component propositions. The arguments for this are based on a consideration of the larger context of APr 2.2–4. A reconstruction of the argument using propositional variables does not fully capture Aristotle’s intentions. (shrink)

In this paper, we provide a detailed critical review of current approaches to ecthesis in Aristotle’s Prior Analytics, with a view to motivate a new approach, which builds upon previous work by Marion & Rückert (2016) on the dictum de omni. This approach sets Aristotle’s work within the context of dialectic and uses Lorenzen’s dialogical logic, hereby reframed with use of Martin-Löf's constructive type theory as ‘immanent reasoning’. We then provide rules of syllogistic for the latter, and provide proofs of (...) e-conversion, Darapti and Bocardo and e-subalternation, while showing how close to Aristotle’s text these proofs remain. (shrink)

Nous savons bien aujourd'hui que, dès l'Antiquité, leCorpus Aristoteli-cuma été constitué, mis en ordre et commenté de manière à faire ressortir, en tout, la cohérence des doctrines du Stagirite, dont ses écrits, tels qu'il nous les a laissés, ne portaient pas la marque évidente. Le sentiment que ce travail de mise en forme, poursuivi par la tradition, devait avoir oblitéré quelque chose de la nature de la pensée aristotélicienne conduisit à soulever la question qui sert d'intitulé à la présente étude.

My dissertation is devoted to an examination of the resolution of fallacy in Plato's Euthydemus. It is a familiar claim that the Euthydemus champions Socratic argumentation over sophistical or eristic reasoning. No consensus however exists regarding either the nature or philosophical significance of Socrates’ treatment of the fallacies he confronts. I argue that a careful reading of the dialogue reveals that the Socratic response to fallacious reasoning is conducted at two different levels of philosophical sophistication. Socrates relies upon the resources (...) of Socratic dialectic in responding to sophisms due to ignorance of refutation. Insofar as Socratic dialectic is grounded in a grasp of the nature of genuine refutation, the objections it raises to false refutation are fully explanatory. On the other hand, Socrates employs various self-refutation arguments against theses which depend on false assumptions regarding the nature of predication---for example, the thesis that false speaking is impossible. It is however characteristic of Socratic dialectic that this method of examination cannot explain why the sophists’ theses are false. The Socratic response to fallacy in these cases is non-explanatory in this sense. On the other hand, these limitations on Socratic expertise are overcome in other passages in the dialogue which are replete with clues to the reader that point to a genuine explanation and resolution of the sophists’ arguments for their various theses. In particular, the reader is invited at every turn to modify, clarify, or reject various assumptions made by the brothers regarding the nature of predication. Here Plato implicitly relies on the results of what I call higher dialectic. This theory, which receives explicit formulation in the Sophist, is conceptually rich enough to expose and dispose of the various false assumptions upon which the sophists’ theses rest. I conclude that the Euthydemus is concerned to identify Socratic dialectic as only a part of philosophy, and to locate and strictly delimit its epistemological status as lying above eristic and the rhetorical arts, but below that of dialectic as that is conceived in the Republic and even later dialogues---thus anticipating the Sophist’s conception of Socrates as the practitioner of a ‘noble sophistry’, and the elenchus as a propaedeutic to philosophy, which purges the soul of false beliefs. (shrink)