The Fate of Fallacies

Le destin des sophismes

M Dufour (1)

1 Université Sorbonne Nouvelle - Paris 3

The fate of fallacies: the Port-Royal turn Almost half a century ago, Hamblin worried about the absence of a genuine theory of fallacies. Today, there is still no consensus on a definition of fallacies beyond a possible agreement on the vague general idea that it is a reasoning that goes wrong in some way. Perhaps, no theory is needed to do what has been done for centuries, namely to give more or less famous examples of fallacies, a practice quite compatible with the idea that this field is fluctuating and has fuzzy borders. Yet, a salient feature of fallacies studies is the importance of tradition. For instance, most contemporary theoretical approaches have something to say about all or parts of the Aristotelian fallacies. There are also national traditions. The study of fallacies has been a lively topic in the anglo philosophical tradition but is no topic at all in the French philosophy of the three last centuries. If you compare some recent books with other ones written a few centuries ago, the field seems to grow. On the other hand, some fallacies seem to have disappeared or have become negligible, or have been clouded by others. Think, for instance, of the Aristotelian paralogism of accent or the difference between the old and the contemporary version of the composition and division fallacies. How and why do some arguments win or lose the status of fallacy? This is a whole research program. The process of translation seems to be an acceptable answer, for instance in the case of the fallacy of accent, since not all languages are accentuated. The rise of the probability calculus could also explain the emergence of sensitivity to some inductive fallacies. I will discuss the important changes made by the Port-Royal Logic, published in 1662. It made an influential turn not only in the field of fallacies but in the whole field of logic. As far as fallacies are concerned, it discarded some traditional fallacies that it considered “too rude” to deserve serious attention. It also introduced other ones, of a new type. My point is that the sharp updating made by ts two chapters on fallacies is a consequence of deeper changes motivated by important contemporary philosophical, religious, and political views which had broad consequences not only in other parts of the book but beyond. The first radical change is that the Port-Royal Logic respectfully stood aloof from Aristotle, hence from his theory on paralogisms. The Logic drops the distinction between intra and extra dictionem fallacies and the number of « sophisms » (the very term used by the Logic) inspired by Aristotle is reduced to seven. So, six of the thirteen fallacies of On sophistical refutations disappeared or have been disqualified. This attitude towards Aristotle is not an exception at this time, but it is a significant shift from the traditional approach of fallacies, roughly faithful to the Philosopher. Three modern influences shape the chapters on fallacies: the Cartesian philosophy, the Jansenist ethic, and the taste of the day for pleasant rhetoric. Three types or styles of discourse can be associated with these three influences. Each of them has its own requirements and goals that contribute to challenging the supremacy of the juridical style of the disputes of the School. Textual evidence of these influences can be found in the chapters on fallacies. The Logic makes an eloge of Descartes and explicitly borrows from his philosophy in many places. More specifically, it follows Descartes in his project of a reasoned search for truth that can't be satisfied by a disputative dialectic, only good to provide short already known explanations, while Descartes's discursive scientific model requires the geometers' fertile « long chains of reasons ». The impact of Cartesianism on Port-Royal Logic includes the introduction of two inductive sophisms inspired by the very principles of Descartes's method. Like their friend Blaise Pascal, the authors were Jansenists, hence fervent supporters of rigorous Augustinism. One of its tenets is that without God's grace, men are condemned to sin. Hence the frequent explanations calling to the bad morality of arguers and the introduction of a surprising distinction between scientific fallacies and fallacies made in daily and/or « civil » life. According to the Logic, the second kind of fallacy is morally more important, since science is a futile distraction when compared to the duty to be a good person. This justifies the existence of two separate chapters. This moral precedence could also be the reason for the inflation of the second chapter between the first and the second edition of the book. The discursive style of this chapter, far from dialectical disputes, is closer to the concern of a priest who has to make a sermon addressed to sinners to help them not to become the victims of their self-love and to resist the temptations of heresy or skepticism. The importance of the taste of the day for pleasant rhetoric cannot be as easily linked to an individual figure patronizing the Logic, like Descartes or Pascal in other chapters. Yet, especially if we look at the content of the second chapter on fallacies, we can recognize the general tendency of the century to link clear and good ideas or reasoning with the use of a « natural » and « easy » verbal expression which was held as a sign of the right use of reason. This pleasant naturalness is also associated with the civil and elegant use of language by “gentlemen”. Textual evidence of this tendency can be found in the second chapter on fallacies.

Mots clés: Port-Royal; Fallacies; Sophisms; Jansenism; Ethic

Domaines: Sciences de l'Homme et Société

M Dufour. The Fate of Fallacies. Poznan Reasoning Week, Department of Logic and Cognitive Science, Institute of Psychology, Adam Mickiewicz University, Jul 2017, Poznan, Poland. ⟨hal-03941713⟩