Aristotle's Syllogistic and Core Logic

I use the Corcoran–Smiley interpretation of Aristotle's syllogistic as my starting point for an examination of the syllogistic from the vantage point of modern proof theory. I aim to show that fresh logical insights are afforded by a proof-theoretically more systematic account of all four figures. First I regiment the syllogisms in the Gentzen–Prawitz system of natural deduction, using the universal and existential quantifiers of standard first-order logic, and the usual formalizations of Aristotle's sentence-forms. I explain how the syllogistic is a fragment of my (constructive and relevant) system of Core Logic. Then I introduce my main innovation: the use of binary quantifiers, governed by introduction and elimination rules. The syllogisms in all four figures are re-proved in the binary system, and are thereby revealed as all on a par with each other. I conclude with some comments and results about grammatical generativity, ecthesis, perfect validity, skeletal validity and Aristotle's chain principle.     

Aquinas on Quality

For Kant, Aristotle's categories are arbitrary but brilliant and they do not ultimately correspond to extramental reality. For Aquinas, however, they are rational divisions of extramental being. In this perennial and ongoing dispute, the various positions seem to dissolve upon delving into the particulars of any one category. If, however, the categories are divisions of extramental being, it should be possible to offer plausible accounts of particular categories. I offer Aquinas's unstudied derivation of quality as a test case to see how one could hold, and how Aquinas did hold, to a realism about Aristotle's categories at a highly specific level. Although Aristotle divides quality into four species and some further subspecies, unlike Aquinas, he offers no reasons for these divisions. For Aquinas each accident is a particular mode of existing, that is, it is a particular way that an accident exists in a substance. In the case of quality, this mode of existing follows substantial form and its real extramental causes or effects further divide it into four species. Aquinas's account is both compelling and original, inspired by Aristotle but also un-Aristotelian. The paper concludes by comparing Aquinas's account of quality with the best extant account of Aristotle's quality, namely, Paul Studtmann's.     

Two conceptions of voluntary action in the Nicomachean Ethics

It is nearly universally agreed among commentators that according to Aristotle's account of voluntary action in the Nicomachean Ethics (NE), only voluntary actions are blameworthy. I argue for a qualified rejection of this assumption: some actions that Aristotle counts as blameworthy do not meet the criteria for voluntariness set out in NE 3.1. However, in NE 3.5 and elsewhere, one finds a broader conception of voluntary action, and it is true that, for Aristotle, an action must be voluntary on this broader conception in order to be blameworthy. While the narrow conception only counts actions that are under the agent's direct control as voluntary, the broader conception includes also actions that are under the agent's indirect control. The compresence of these two conceptions in the NE is not simply a matter of sloppiness on Aristotle's part. Rather, he has good philosophical reasons for employing both.     

Term Kinds and the Formality of Aristotelian Modal Logic

Recent formalizations of Aristotle's modal syllogistic have made use of an interpretative assumption with precedent in traditional commentary: That Aristotle implicitly relies on a distinction between two classes of terms. I argue that the way Rini (2011. Aristotle's Modal Proofs: Prior Analytics A8–22 in Predicate Logic, Dordrecht: Springer) employs this distinction undermines her attempt to show that Aristotle gives valid proofs of his modal syllogisms. Rini does not establish that Aristotle gives valid proofs of the arguments which she takes to best represent Aristotle's modal syllogisms, nor that Aristotle's modal syllogisms are instances of any other system of schemata that could be used to define an alternative notion of validity. On the other hand, I argue, Robert Kilwardby's ca. 1240 commentary on the Prior Analytics makes use of a term-kind distinction so as to provide truth conditions for Aristotle's necessity propositions which render Aristotle's conversion rules and first figure modal syllogisms formally valid. I reconstruct a suppositio semantics for syllogistic necessity propositions based on Kilwardby's text, and yield a consequence relation which validates key results in the assertoric, pure necessity and mixed necessity-assertoric syllogistics.     

ARISTOTLE'S ETHICAL EGOISM

Accepting the controversial thesis that Aristotle is an ethical egoist, I argue that Aristotle's brand of ethical egoism is immune to four important objections to such a position. I analyse the causes of the four objections showing (a) that Aristotle does not have a conception of happiness which would give rise to the first three, and (b) that his account of practical reasoning, of which I provide an original interpretation, can deal with the fourth.     

Aristotle's Cognitive Science: Belief,Affect and Rationality

I offer a novel interpretation of Aristotle's psychology and notion of rationality, which draws the line between animal and specifically human cognition. Aristotle distinguishes belief (doxa), a form of rational cognition, from imagining (phantasia), which is shared with non‐rational animals. We are, he says, “immediately affected” by beliefs, but respond to imagining “as if we were looking at a picture.” Aristotle's argument has been misunderstood; my interpretation explains and motivates it. Rationality includes a filter that interrupts the pathways between cognition and behavior. This prevents the subject from responding to certain representations. Stress and damage compromise the filter, making the subject respond indiscriminately, as non‐rational animals do. Beliefs are representations that have made it past the filter, which is why they can “affect [us] immediately.” Aristotle's claims express ceteris paribus generalizations, subject to exceptions. No list of provisos could turn them into non‐vacuous universal claims, but this does not rob them of their explanatory power. Aristotle's cognitive science resolves a tension we grapple with today: it accounts for the specialness of human action and thinking within a strictly naturalistic framework. The theory is striking in its insight and explanatory power, instructive in its methodological shortcomings.     

TELEOLOGY PAST AND PRESENT

Abstract. Current teleology in Western biology, philosophy, and theology draws on resources from four main Western philosophers. (1) Plato's Timaeus shows how to interpret the universe as the handiwork of a purposive Creator who subordinates secondary, necessary, causes to primary, intelligent, causes. (2) Aristotle's Physics sets forth purpose as implicit in the nature of things. Purposes of different sorts inhere in different types of being, and everything has a natural function. Living things grow to actualize the potentials of the goal whose principle they bear within themselves. (3) Kant's Critique of Judgment denies that purpose is anything that human beings can know, strictly speaking. Nevertheless, purpose is a concept we must use to make sense of biological systems. (4) Hegel's Philosophy of Nature articulates organic systems as dialectically including and transcending mechanical and chemical systems. Teleological themes persist, in different ways, in contemporary discussions; I consider two lines of criticism of traditional teleology—by Richard Dawkins and Stephen Jay Gould—and one line that continues traditional teleology in an updated way—by Holmes Rolston, III.     

What's Aristotelian about neo‐Aristotelian Virtue Ethics?

It is commonly assumed that Aristotle's ethical theory shares deep structural similarities with neo‐Aristotelian virtue ethics. I argue that this assumption is a mistake, and that Aristotle's ethical theory is both importantly distinct from the theories his work has inspired, and independently compelling. I take neo‐Aristotelian virtue ethics to be characterized by two central commitments: (i) virtues of character are defined as traits that reliably promote an agent's own flourishing, and (ii) virtuous actions are defined as the sorts of actions a virtuous agent reliably performs under the relevant circumstances. I argue that neither of these commitments are features of Aristotle's own view, and I sketch an alternative explanation for the relationship between virtue and happiness in the Nicomachean Ethics. Although, on the interpretation I defend, we do not find in Aristotle a distinctive normative theory alongside deontology and consequentialism, what we do find is a way of thinking about how prudential and moral reasons can come to be aligned through a certain conception of practical agency.     

Polarity and Inseparability: The Foundation of the Apodictic Portion of Aristotle's Modal Logic

Modern logicians have sought to unlock the modal secrets of Aristotle's Syllogistic by assuming a version of essentialism and treating it as a primitive within the semantics. These attempts ultimately distort Aristotle's ontology. None of these approaches make full use of tests found throughout Aristotle's corpus and ancient Greek philosophy. I base a system on Aristotle's tests for things that can never combine (polarity) and things that can never separate (inseparability). The resulting system not only reproduces Aristotle's recorded results for the apodictic syllogistic in the Prior Analytics but it also generates rather than assumes Aristotle's distinctions among ‘necessary’, ‘essential’ and ‘accidental’. By developing a system around tests that are in Aristotle and basic to ancient Greek philosophy, the system is linked to a history of practices, providing a platform for future work on the origins of logic.     

Three kinds of reliabilism

Abstract

The distinction between acting and suffering underlies any theory of agency. Among contemporary writers, Fred Dretske is one of the few who has attempted to explicate this distinction without restricting the notion of action to intentional action alone. Aristotle also developed a global account of agency, one which is deeper and more detailed than Dretske's, and it is to Aristotle's account (with some modifications) that the bulk of this paper is devoted. Dretske's sketchier theory faces at least two ground-level problems. It is shown in the course of the paper how these can be handled by the Aristotelian account, in a way which is friendly to Dretske's approach.     

Autonomy as Second Nature: On McDowell's Aristotelian Naturalism

The concept of second nature plays a central role in McDowell's project of reconciling thought's external constraint with its spontaneity or autonomy: our conceptual capacities are natural in the sense that they are fully integrated into the natural world, but they are a second nature to us since they are not reducible to elements that are intelligible apart from those conceptual capacities. Rather than offering a theory of second nature and an account of how we acquire one, McDowell suggests that Aristotle's account of ethical character formation as the acquisition of a second nature serves as a model that can reassure us that thought's autonomy does not threaten its naturalness. However, far from providing such reassurance, the Aristotelian model of second nature actually generates an anxiety about how the acquisition of such autonomous conceptual abilities could be possible.     

Two Cultures Revisited: New Widening Gaps

Aristotle continues to be a highly cited author in cultural sciences (human and social sciences) and humanities. In the last two decades, his work attracted up to a hundred times more attention than the work of Konrad Lorenz or Edward O. Wilson, who have attempted to synthesize new knowledge on behavior and society and proposed alternatives to traditional, intuitively appealing, explanations. Aristotle's interpretations of the world, which appear to be intuitive to the human mind, were abandoned in natural sciences upon introduction of the experimental method. Human intuition may have been appropriate in conditions under which it was originally selected: for life of small non-anonymous groups of hunters and gatherers in the savannah. Intuition confines human understanding to a simple reality circumscribed by a boundary that can be called Aristotle's barrier. The barrier may only be crossed by experimentation, which is largely missing in cultural sciences. Snow's concept of two cultures may be revisited to characterize a splitting of natural sciences versus cultural sciences. It may also be applied to a widening gulf between science and technoscience. Diverging of the two cultures may have far-reaching consequences for prospects of humankind's survival.     

The Different Ways in which Logic is (said to be) Formal

I argue that, in the Prior Analytics, higher and above the well-known ‘reduction through impossibility’ of figures, Aristotle is resorting to a general procedure of demonstrating through impossibility in various contexts. This is shown from the analysis of the role of adunaton in conversions of premises and other demonstrations where modal or truth-value consistency is indirectly shown to be valid through impossibility. Following the meaning of impossible as ‘non-existent’, the system is also completed by rejecting any invalid combinations of terms in deductions or conversions. The notion of impossibility reaches the core of Aristotle's system in the Prior Analytics. On the one hand, the use of adunaton shows that he is following one of the two requisites for demonstrative science formulated in the Posterior Analytics, i.e. to demonstrate that it is impossible for things to be otherwise than stated. On the other hand, that demonstrations through impossibility are rooted in the notion of contradiction supports the claim that Aristotle might have been trained to use this specific procedure in the context of dialectical exercises in the academy. This need not rule out other influences on Aristotle's preferred procedures of proving or counter-proving, but it paves a way to a better understanding of Aristotle's logic under the light of Plato's dialectic.     

Active power and causal flow in aristotle's theory of vision

Aristotle's theory of vision has been characterized as naive, incommensurate with his theory of audition, and of historical interest only. This view is based on an analysis which fails to acknowledge the role of the concepts acting upon and active power in the theory. The meaning of these terms and the role Aristotle assigned them in vision and in sensation generally is demonstrated. It is argued that with the inclusion of these concepts (1) the theory of vision is sufficiently sophisticated and modern to be more than comparable with more recent perceptual theorizing, and (2) the overall integrity of Aristotle's sensory philosophy is preserved. It is further argued that given the cohesiveness and comprehensiveness of Aristotle's psychological works, more attention should be given them by modern psychologists.     

Metaphysics XII 7, 1072A27-B1: An Argument of Identity

The paper analyses the argumentative structure of a difficult passage from Aristotle's Metaphysics XII 7 on the basis of a topos of sameness provided in Top. VII 1. In doing this the article gives an example of how Aristotle's treatises on dialectic can prove useful to understand what he says in his more philosophically committed writings. The article also shows how general argumentative techniques and more or less explicit specific philosophical assumptions interact in shaping Aristotle's arguments and how the distinction of these different factors can help us have a better grasp on Aristotle's text.     

Pity: a mitigated defence

The aim of this article is to offer a mitigated moral justification of a much maligned emotional trait, pity, in the Aristotelian sense of ‘pain at deserved bad fortune’. I lay out Aristotle's taxonomic map of pity and its surrounding conceptual terrain and argue – by rehearsing modern accounts – that this map is not anachronistic with respect to contemporary conceptions. I then offer an ‘Aristotelian’ (albeit not Aristotle's) moral justification of pity, not as a full virtue intrinsically related to eudaimonia but as a positive moral quality that has instrumental value in developing and sustaining a certain intrinsically valuable state of character – namely compassion. The justification offered is mitigated in the sense that it does not elevate pity to a virtuous disposition, constitutive of the good life; yet it does offer a crucial counterweight to Aristotle's own denunciation of pity.     

Aristotle on Necessary Verticality,Body Heat,and Gendered Proper Places in the Polis: A Feminist Critique

Feminist critics have charged that Aristotle's mistaken and harmful remarks about women and slaves show inconsistency or bias-driven arbitrariness. However, this analysis shows that these remarks function within a consistent and coherent theoretical corpus. Thus, both Aristotle's hierarchical and dualistic first principles and the methodology on which his entire corpus is based must be unreliable. Moreover, consistency and coherence must be insufficient warrants of theoretical insightfulness. Aristotle's mistakes suggest caveats for feminist philosophical reconstruction.     

The Birth of Being and Time: Heidegger's Pivotal 1921 Reading of Aristotle's On the Soul

During the 1920s Heidegger gave no less than twelve seminars and lecture courses devoted either exclusively or in large part to the reading of Aristotle's texts. Seven of these, especially the smaller seminars for advanced students, have not been published and apparently will never be included in the Gesamtausgabe . My focus here is on the very first of these. Billed as a reading of Aristotle's De Anima , much of it was devoted to Aristotle's Metaphysics . This decision not to separate Aristotle's “psychology” from his “ontology” is a key move of the seminar that anticipates the project of Being and Time . This and many other ways in which Heidegger's early reading of De Anima anticipates the key moves of the later book constitute one of the reasons for its importance. Another is that the seminar allows us to see what gets suppressed in Heidegger's reading of Aristotle, most significantly, the phenomenon of life itself in favor of an eventual focus on the being of human life or Dasein. This early seminar thus enables us not only to better understand Heidegger's project, but also to raise some fundamental questions concerning it.     

Love and Benevolence in Hutcheson's and Hume's Theories of the Passions

In this paper I consider two related issues raised by Aristotle's treatment of hearing and sounds. The first concerns the kinds of changes Aristotle takes to occur, in both perceptual medium and sense organs, when a perceiver hears a sounding object. The second issue concerns Aristotle's views on the nature and location of the proper objects of auditory perception. I argue that Aristotle's views on these topics are not what they have sometimes been taken to be, and that when rightly understood they compare favourably in many respects with leading contemporary accounts.     

Philosophical Sensitivity

Although much has been written about the nature of philosophy and how the discipline can be defined, little attention has been paid to the ways we develop the facility to reflect philosophically or why cultivating this ability is valuable. This article develops a conception of “philosophical sensitivity,” a perceptual capacity that facilitates our awareness of the philosophical dimension of experience. Based in part on Aristotle's notion of a moral perceptual capacity, philosophical sensitivity starts with most people's natural inclinations as children to reflect about life's fundamental mysteries; when this capacity is cultivated with training over time, our attentiveness to the philosophical features of ordinary life becomes almost second nature. In much the same way an aesthetically sensitive person notices certain qualities of experience not readily perceptible by others, philosophical sensitivity involves the development of a particular way of seeing the world.