Francesco Binotto

Dans la Physique, II, 5, Aristote définit l’événement fortuit comme un phénomène attribué au hasard, qui survient dans une minorité de cas dans le cadre des actions humaines. Cependant, le texte ne précise pas les conditions nécessaires à l’apparition d’un tel événement. Les commentateurs médiévaux de la Physique ont cherché à combler cette lacune. Cet article s’attache à comparer les interprétations proposées respectivement par Albert le Grand, Thomas d’Aquin, Siger de Brabant et Boèce de Dacie. Plus particulièrement, il examine la manière dont ces auteurs rendent compte de l’occurrence des événements fortuits et leur conception du statut des causes accidentelles.

This article examines Hervaeus Natalis’s rejection of astral determinism, that is, the thesis that the movements of heavenly bodies make all sublunary effects necessary. Hervaeus develops his anti-deterministic arguments in two key texts: Scriptum super iv libros Sententiarum (Book ii, d. 15, q. 1, a. 4) and De materia caeli, q. 9. He argues that celestial causes do not act with absolute necessity, since they can be impeded by external factors such as the action of a contrary agent and the indisposition of sublunary matter. Hervaeus further seeks to ground the contingency of sublunary effects in a notion of causal indeterminacy. The Scriptum attributes this indeterminacy to the unlimited ways in which sublunary matter can be disposed, while the De materia caeli appeals to the indeterminacy of accidental factors that may prevent or promote the occurrence of those effects. The article addresses the difficulties faced by both accounts.

In his Quaestiones in Metaphysicam Siger of Brabant offers his first account of accidental events: an accidental event coincides with the defect of an agent, which achieves its effect in most but not all cases. Siger provides three examples of accidental events: the case of a cold and wintry weather during the dogdays; the case of a man finding treasure while digging a grave; and the meeting between a creditor and his debtor. I show that the last two examples are not fully consistent with Siger’s account since they do not reflect the idea of an accidental event as the defect of an agent that achieves its effect in most cases. A possible solution to this inconsistency can also be found in Siger’s Quaestiones in Metaphysicam, and precisely in what I call the second account of accidental events. According to this second account, an accidental event identifies every simultaneous concomitance between two items, which are not connected with each other by a per se causal relationship. This second account does not imply a rejection of the first account, but rather includes it: the relationship between (the action of) an agent for the most part and its defect may be considered a particular case of concomitance between two items, where one is not the per se cause of the other, and vice versa.

In this paper I discuss Siger of Brabant’s anti-deterministic argument as developed in De necessitate et contingentia causarum. First, I offer an in-depth reconstruction of how Siger justifi es the contingency of effects in nature: the contingent status of an effect depends only on (the contingent status of) its proximate cause, and not on the First Cause. According to Siger, the First Cause, which is understood as a necessary cause, only determines the necessity of its immediate effect. I, then show that such an account runs into an impasse: it is, in fact, impossible to justify how there can be contingent (i.e., impedible) secondary causes in the chain of causes, once it has been assumed that the First Cause is a necessary (i.e., nonimpedible) cause which immediately produces a necessary effect.

This discussion note aims to call into question the first part of Gloria Frost’s article, Aquinas and Scotus on the Source of Contingency, devoted to Aquinas’s thought on the source of contingency in creation. I shall discuss three controversial claims that represent the key points of Frost’s interpretation of Aquinas’s account on contingency: with re spect to existence, every creature exists contingently on the grounds that no creature is necessarily willed by God; with respect to cause-and-effect relationship, only those effects that derive from a voluntary cause are contingently caused; God’s will, as a voluntary cause, is a contingently operating cause and thus cannot immediately produce a necessary effect. According to my analysis, Frost’s misinterpretation of Aquinas’s position on contingency in creation derives from the erroneous assumption that, for Aquinas, the freedom of a cause implies the contingency of such a cause and of all the effects following from it. I shall prove that Frost’s misunderstanding consists in neglecting that Aquinas does not endorse this co-implication between freedom and contingency: in fact, if the freedom of a cause indicates that it can refrain from producing its effect, the contingency of a cause means its mutability and fallibility, namely that it can be prevented in producing its effect.