The Logic or the Art of Thinking, also called Port-Royal Logic, is an exemplar of modern reformers in logic and epistemology. Its reformism has a marked influence of Descartes, who introduces the epistemic and logical subject into the ground of justification of knowledge and judgment. A look at the method’s commitments in this text may shed light on the dynamics of the interweaving between epistemology and logic. It is in this perspective that an analysis of the use of the Aristotelian (...) notion of “techné”, as an “art of doing anything well” seems to require attention, since it happens in a logical domain, as the authors make it. In this paper I want to make clear that the mental actions are crucial to a logic as reflexive practice. And, because of that, the very expression of “art of thinking” shows itself as non-trivial, that is, as a requirement of method. (shrink)

Il y a un certain nombre d'années que je lis quotidiennement des articles ou des ouvrages concernant l'histoire des théories linguistiques. J'ai rarement éprouvé autant de plaisir qu'à la lecture du livre de Marc Dominicy. Je crois qu'il y a à cela une raison tres claire: c'est la façon de travailler de l'auteur. Pour lui, d'une part les théories formulées dans le passé sont descriptibles dans une langue moderne qui les rend comparables entre elles et avec les theories plus modernes, (...) d'autre part la pratique historiographique est cumulative. Le second point est sans doute dans son esprit une conséquence du premier, ou du moins il est la conséquence d'un axiome très fort assurant l'existence d'un principe de démarcation entre la science et la non-science. Je pense qu'on peutfaire l'économie du principe de démarcation, si on part du principe que l'historiographie doit être cumulative. Cela suppose en effet que l'historien discute des représentations de prédécesseurs, mais plus encore que les leurs comme les siennes soient discutables, et par conséquent qu'elles soient formulables dans un Iangage qui les rende comparables. Dans le livre de l'auteur cela se traduit doublement par: a) une bibliographic importante et l'attribution assez générale, dans le cours du texte, des thèses avancées à ceux qui les ont émises; b) une représentation formalisée de la théorie qu'il décrit. Il y a là une grande rigueur autant méthodologique que déontologique. (shrink)

Anselm of Cantorbery wrote Proslogion, where is formulated the famous ‘Unum argumentum’ about the existence of God. This argument was been disputed and criticized by numerous logicians from an extensional view point. The classical predicate logic is not able to give a formal frame to develop an adequate analysis of this argument. According to us, this argument is not an ontological proof; it analyses the meaning of the “quo nihil maius cogitari posit”, a characterization of God, and establish, by absurd, (...) that “quod non posit cogitare non esse” by using the hypothesis: “to think in re” is taller than “to think in solo intelectu”. We discuss this relation and the difference between the meanings of the elementary predicates ‘to be in re’, ‘to be in intellectu’ and ‘to be in solo intellectu’. We propose a new logical approach of this ‘Unum argumentum’ of Anselm by using Curry’s Combinatory Logic. Indeed, Combinatory Logic is an abstract applicative formalism of operators applied to operands; in this formalism, the predicates, viewed as specific operators, can be composed and can be transformed, by an intrinsic way, into more complex predicates, by means of abstract operators, called “combinators”, studied by Combinatory Logic. We show that this formalism is a logical frame where it becomes possible to discuss and to formulate cognitive representations of the meanings of predicates used inside of the ‘Unum argumentum’ and to explain how the argument runs. (shrink)

Rhetoric is at present the object of a rehabilitation on a grand scale, all the more as it overlaps the fields of literature, linguistics, and philosophy. Actually, if philosophy rejects and removes rhetoric, it is nevertheless, as a method of word, wholly impregnated with it. To investigate the complex relationship of mutual implication in which rhetoric and philosophy are involved is part and parcel of this plan of re-evaluation of rhetoric as “discourse art” with a view to a re-definition of (...) its field and functions. In this perspective, rhetoric articulates itself within, in relation to, and with Plato's dialogues in a much more subtle and complex manner than warranted by the process of “anti-rhetoricalness” initiated by philosophy against rhetoric after Plato. Going back to the origins of this conflict and recalling the system of oppositions supporting the official Platonic vulgate, this study begins to pave the way for a micr-reading of the Platonic text regarded as a paradigm of philosophic textuality. It is certainly true that the Phaedrus, the Gorgias, and the Symposium set up a system of oppositions between between rhetoric and dialectrics which are in contrast with each other in the word practices, in the rules and methods of discourse, and which are antinomic in their ends. This system of oppositions always seems to be referable to the opposition between “speaking fair” and “speaking the truth”. But the strategies and procedures set going in the Symposium, in particular in “Agathon's speech” and in “Diotima and Socrates' speech” betray a much closer connection between the supposed “bad rhetoric” revealed by Phaedrus and the “good rhetoric” which is dialectrics.The search for this connection is conducted through two types of reading of the Symposium. In actual fact, between the paronomasia on the agathoi and that on “Gorgias' head” (this Gorgon of rhetoric) there takes place a speech, Agathon's, whose parodied, exacerbated, and counterfeit rhetoric allows us to gauge Plato's own rhetoric in this artefact which distances itself, more or less openly, from Gorgian rhetoric. This “hyper-rhetoricalness” and “over-grammaticalness” cannot be there with the sole aim of serving as evidence against rhetoric. It is in fact possible to perceive through the web of the text the ends, quite rhetorical themselves, which preside over the structure of Agathon's speech, seen from the viewpoint of the figure of the antithesis.Thus, it is in the play of a “neo-rhetoricalness” where we must, in the last analysis, look for the spring allowing the philosophical discourse to overturn the rhetorical one. And while in Giorgias what clothes the discourse is actually the truth, in Plato it is the antinomy between “speaking fair” and “speaking the truth”, conveniently set up, which forms the basis of the function of diversion by which Socrates points out — in the complex network of the continuity and discontinuity existing between rhetoric and philosophy — the structures of reversal and the original upheavals which Plato imposes on the relation between rhetorical and dialectric discourse. Actually, dialectrics is found in “Socrates and Diotima's speech”, not as “anti-rhetoric”, but rather as a “transposition” of the rhetorical discourse, thus acquiring the traits of a “neo-rhetoric”. The analysis of this discourse, which constitutes the second reading exercise of the Symposium, allows us to pick out the aversion and inversion strategies that turn dialectrics in an overtuned rhetoric. The founding deed of this “inversion” (rather than “separation”) is recognizable in the alteration it introduces in the first plase in the type of discourse, which from a rhetorical, explicitly addressed, macrological, monological, and continuous discourse turns into a dialectical, brachylogous, dialogic discourse with partners and interlocutors, i.e. into a dialogue; in the second place, the subject of the discourse shifts from the locuteur, author and signer of the discourse to ever-present interlocutors who end up by making room for a talking and knowing speaker in a regime of anonymous subjectivity: this is an extreme alteration of the anthropological and epistemic subject, culminating in the scientific discourse of Euclidean geometry. Finally, the inversion is recognizable in the object of the discourse, whose prâgma slips from being the predicate of a qualified grammatical subject into a process of objectivation and substantivation, thereby moving from the rhetorical question “What is beautiful?” to the philosophical question “What is the beautiful?”.The hypothesis of a “neo-rhetoricalness” of dialectics, underlying this research, is therefore more Platonic than it appears, insofar as between rhetoric and dialectics there has been a tradition which has tried to wipe out the traces of its transmission, but where the neo-rhetoricalness of dialectics shows through quite clearly, taking advantage, without admitting it, from a more ancient rhetoric than it is itself. (A.T.). (shrink)