De l'esprit géométrique et L’art de persuader

Description

Besides in the Pensées, this is his only work on the philosophy of science. It seems to be about the regress problem. In it, he discusses the certainty of first principles, which St. Thomas says are known in a "scientific manner":

Expositio Posteriorum , lib. 1 l. 7:

Therefore, if someone were to ask how the science of immediate principles is possessed, the answer would be that not only are they known in a scientific manner, but knowledge of them is the source of a science. For one passes from the knowledge of principles to a demonstration of conclusion on which science, properly speaking, bears. But those immediate principles are not made known through an additional middle but through an understanding of their own terms. For as soon as it is known what a whole is and what a part is, it is known that every whole is greater than its part, because in such a proposition, as has been stated above, the predicate is included in the very notion of the subject. And therefore it is reasonable that the knowledge of these principles is the cause of the knowledge of conclusions, because always, that which exists in virtue of itself is the cause of that which exists in virtue of something else.

Seeing that many people have claimed Duhem is a Pascalian— vide e.g.

1. Jean-François Stoffel, “Pierre Duhem : Un Savant-Philosophe Dans Le Sillage de Blaise Pascal,” Revista Portuguesa de Filosofia 63, no. 1–3 (2007): 275–307;

2. Jean-François Stoffel, “Blaise Pascal Dans l’œuvre de Pierre Duhem,” ed. Robert HALLEUX and Anne-Catherine BERNÈS (Nouvelles tendances en histoire et philosophie des sciences / Nieuwe tendenzen in de geschiedenis en de filosofie van de wetenschappen : colloque national / nationaal colloquium, Bruxelles: Palais des Académies, 1993), 53–81.

—I read Pascal's De l'esprit géométrique and the short § on Pascal of Copleston, S.J., where he quotes, on p. 164 of A History of Philosophy (vol. 4): Descartes to Leibniz, the following from Pascal's Pensées, S142/L110:

Nous connaissons la vérité non seulement par la raison mais encore par le cœur. C'est de cette dernière sorte que nous connaissons les premiers principes…

We know truth not only by the reason but also by the heart. It is in this second way that we know the first principles.

Pascal's cœur thus seems akin to Aristotle's νόος or the Scholastics' intellectus , and his raison seems to be Aristotle's ἐπιστήμη or the Scholastics' scientia:

Magna Moralia I, c. 34, 1197a20-23:

Intelligence [intellectus , νοῦς] deals with the principles [ἀρχὰς] of intelligibles and of beings. For science [scientia , ἐπιστήμη] deals with beings that have proof [ἀποδείξεως], but the principles are without proof [ἀναπόδεικτοι], so that science would not deal with principles; rather intelligence would.

cf. Posterior Analytics 72b5-24

Is this true?

According to Duhemian Ariew's ed. of the Pensées, Pascal did read the Summa , St. Thomas's commentary on St. John, etc. Duhem (and Galileo, too!) was familiar with Aristotle's "Second Analytique " (Le Système du Monde tome 1 pp. 130-134).

Also, from what I read in Copleston, Pascal seems to be a fidest; his "wager" argument, e.g., reminds me of Lamentabili 's condemned "25. The assent of faith ultimately rests on a mass of probabilities." Pascal's desire for a philosophical method attaining certainly doesn't seem much different from Descartes's ambitions; Pascal's "geometry" (which he takes in a broad sense) seems to be Decartes's "mathematics". (I'm also surprised Grattan-Guinness doesn't mention Pascal much at all, despite Pascal's association with Port Royal.)

felix festum Inventione Sanctæ Crucis<>

Non enim judicavi me scire aliquid inter vos, nisi Jesum Christum, et hunc crucifixum.

penseesdepascal.fr has a very nice analysis of his Différence entre l’esprit de géométrie et l’esprit de finesse, which mentions Duhem.

L'Art de persuader, 1758
"Réflexions sur la géométrie en général, de l’esprit géométrique et de l’art de persuader"
Blaise Pascal, philosophe, théologien, mathématicien et physicien français (1623-1662)

Ce livre numérique présente "L'Art de persuader", de Blaise Pascal, édité en texte intégral. Une table des matières dynamique permet d'accéder directement aux différentes sections.

Dans "De l’Esprit géométrique et de l’Art de persuader", Pascal étudie la méthode axiomatique en géométrie, particulièrement la question de savoir comment le peuple peut être convaincu par les axiomes sur lesquels les conclusions sont fondées ensuite. Il distingue les vérités qui entrent du cœur dans l'esprit (vérités de la foi) des vérités qui entrent de l'esprit dans le cœur. Seules ces dernières sont à la portée de notre entendement.

Liste des sections:
- 1. Présentation
- 2. Section I - De la méthode des démonstrations géométriques, c'est-à-dire méthodiques et parfaites
- 3. Section II - De l’art de persuader

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About the Author

Blaise Pascal, né le 19 juin 1623 à Clairmont en Auvergne, mort le 19 août 1662 à Paris, est un mathématicien, physicien, inventeur, philosophe, moraliste et théologien français. Enfant précoce, son père l’éduque.