Aristotle: Necessity and Possibility

In De interpretatione 9, Aristotle argues against the fatalist view that if statements about future contingent singular events (e.g. ‘There will be a sea battle tomorrow,’ ‘There will not be a sea battle tomorrow’) are already true or false, then the events to which those statements refer will necessarily occur or necessarily not occur. Scholars have generally held that, to refute this argument, Aristotle allows that future contingent statements are exempt from either the principle of bivalence, or the law of (...) excluded middle. This paper offers a new interpretation of Aristotle’s refutation of fatalism. According to this interpretation, each member of a pair of contradictory future contingent statements, in virtue of expressing modal necessity, is simply false. (shrink)

The present PhD dissertation aims to examine the relation between modality and change in Aristotle’s metaphysics. -/- On the one hand, Aristotle supports his modal realism (i.e., worldly objects have modal properties - potentialities and essences - that ground the ascriptions of possibility and necessity) by arguing that the rejection of modal realism makes change inexplicable, or, worse, banishes it from the realm of reality. On the other hand, the Stagirite analyses processes by means of modal notions (‘change is the (...) actuality of what is virtual insofar as it is virtual’). In other words: to grasp what change is, one has to resort to the modal idiom of potentialities, while the fact that there is change is indicative of the fact that nature is full of modal properties. -/- Aristotle’s modal and kinetic realism finds a negative in the figure of the Megaric Diodorus Kronus. The polemical situation of Greek philosophy has indeed the dialectical advantage of not opposing the Aristotelian position to a sui generis straw man. Both in its reduction of modal judgements to temporal quantifications and in its dissolution of the reality of the state-of-being-in-motion in favour of a cinematographic view of processes, the philosophical figure of reductionist antirealism embodied by Diodorus constitutes an alternative that takes the opposite view of Aristotle’s realism. -/- The present study is structured as a discussion between these two positions. In the face of Diodorus’ antirealist challenges, Aristotle articulates modal and kinetic considerations: the answers he gives to Diodorus’ puzzles thus provide valuable insight into his metaphysics. Moreover, the examination of Aristotle’s and Diodorus’ metaphysics, because of their insight and originality, will not fail to interest the philosopher concerned with the metaphysical foundations of modern physics, insofar as the entanglement between modalities and processes is nowadays at the core of mechanics (phase spaces, path integrals, etc.). (shrink)

Although the commentary on Aristotle’s problematic discussion of slavery is vast, his discussion of nobility receives little attention. The fragments of his dialogue On Noble Birth constitute his most extensive examination of nobility, and while their similarity to the παμβασιλεύς of the Politics has recently been recognized, their relevance to natural slavery has hitherto gone unnoticed. Yet by declaring that true nobles – particularly the god-like ἀρχηγός – preternaturally possess superhuman characteristics, Aristotle precludes their easy inclusion in the kind “human” (...) in a manner inversely mirroring the preternatural subhumanity of natural slaves. Building on recent scholarship which argues that Aristotle’s “defense” of natural slaves is better understood as an indictment, On Noble Birth becomes most coherent if read as a hypothetical investigation into what would be required for “nobility” to name something true rather than equivocal, with the conclusion that “true nobility” is an empty set. (shrink)

This book investigates what change is, according to Aristotle, and how it affects his conception of being. Mark Sentesy argues that change leads Aristotle to develop first-order metaphysical concepts such as matter, potency, actuality, sources of being, and the teleology of emerging things. He shows that Aristotle’s distinctive ontological claim—that being is inescapably diverse in kind—is anchored in his argument for the existence of change. -/- Aristotle may be the only thinker to have given a noncircular definition of change. When (...) he gave this definition, arguing that change is real was a losing proposition. To show that it exists, he had to rework the way philosophers understood reality. His groundbreaking analysis of change has long been interpreted through a Platonist lens, however, in which being is conceived as unchanging. Offering a comprehensive reexamination of the relationship between change and being in Aristotle, Sentesy makes an important contribution to scholarship on Aristotle, ancient philosophy, the history and philosophy of science, and metaphysics. (shrink)

In this essay, I consider some logical treatises and commentaries from the first decades of the 12th century (many of which are still unedited) which contain a discussion on modalities and modal logic. After presenting a short catalogue of these sources and a description of their common features, I shall focus on some definitions of the modal term “necessarium” which are provided in them. As we will see, Abelard and logicians of his time advanced three different characterizations of this term: (...) necessity was either defined in terms of unavoidability (ineuitabilitas), or in terms of immutability and omnitemporality (impermutabilitas, sempiternitas), or again in terms of absolute necessity as opposed to conditioned one (necessitas absoluta vs. determinata). I argue that the temporal understanding of necessity in terms of omnitemporality, inherited from ancient sources and extensively used by Abelard and others in the first years of the twelfth-century, started to disappear in texts datable from around the 1120, perhaps due to several difficulties that were related to this definition when applied in logical contexts. I also discuss how the notion of necessitas determinata was used by Abelard’s contemporaries to qualify the modal status of present and past events, which were generally believed to be necessary only in a “weak” and harmless sense that did not prevent them from being contingent. -/- . (shrink)

This paper focuses on two short dubitationes on animal’s technical abilities, which Pietro Pomponazzi discussed in 1514 and in 1519 while teaching at the University of Bologna and commenting on Aristotle’s Physica, II, t. 80. A comparative analysis between the respective positions, expressed at a distance of five years, allows to retrace the change in Pomponazzi’s thoughts from the period immediately preceding the composition of De immortalitate animae to the writing of the De incantationibus and De fato.

According to most scholars, in the Parts of Animals Aristotle frequently provides explanations in terms of material necessity, as well as explanations in terms of that-for-the-sake-of-which, i.e., final causes. In this paper, I argue that we misunderstand both matter and the way that Aristotle explains things using necessity if we interpret Aristotle as explaining things in terms of material necessity. Aristotle does not use the term “matter” very frequently in his detailed discussions of animal parts; when he does use it, (...) he typically identifies blood as matter. I argue that this is because blood is, for Aristotle, what properly nourishes and grows the other parts of the body and he views nourishment and growth as types of coming-to-be. The second half of the paper turns to necessity as a cause in the Parts of Animals. I argue that in the Parts of Animals Aristotle is not interested in distinguishing between what Aristotle elsewhere treats as very different types of necessity. (shrink)