Sir Anthony Kenny faces his eightieth birthday standing atop a mass of publications that would take me as many years to read if I had to sustain even half of his administrative responsibilities. This alone elicits both admiration and envy. I can hardly wait for his 100 Successful Work Habits to appear.

Granted, most of his more recent publications pertain to the history of philosophy rather than speculative debates, though that ought not to detract at all from his impressive output. On the contrary, having read three of the four volumes of his A New History of Western Philosophy, I am convinced that these will make a more valuable and lasting contribution to philosophy – a field that is still struggling to recover its roots. Kenny has the rare ability to present the ideas of the past as if they were being formulated for the first time today. John Cottingham describes Kenny's approach to the history of philosophy as ‘far from being a merely antiquarian or instrumental discipline’ but ‘in itself a very fruitful way of philosophizing’ (208). In short, Kenny seems firmly committed to the principle that philosophy is a matter of understanding, and that history contributes to our understanding not by mere repetition but recapitulation. Yet recapitulation, as Robert Sokolowski explains, also means ‘to select, to summarize, and to put into hierarchic order’ (The Phenomenology of the Human Person, 78).

This selection of essays in honour of Sir Anthony Kenny does well in selecting and summarizing, but little by way of hierarchic ordering. Perhaps this is simply the nature of the beast: an edited volume is meant to bring together various articles around a person or general theme. Yet the lack of a hierarchic order may also reflect a lack of unity to Kenny's philosophy. His admiration for Aristotle and Wittgenstein is based on their method of handling problems ex tempore without too much concern for establishing the foundations of philosophy. Yet the ability to jump into philosophy at any point also suggests that it has a unity that will also give rise to a hierarchic order. Aristotle's discussion of actuality and potentiality, for example, though seemingly carried out apart from the issue of whether these notions pertain chiefly to physics or ‘metaphysics’, provide a framework for understanding them primarily as metaphysical principles. This seems to have been a key insight that allowed Thomas Aquinas to arrange the sciences under the umbrella of ‘philosophy’ into some kind of order. This is also why I would propose that Christopher Shields' stimulating essay ‘An Approach to Aristotelian Actuality’ is the linchpin of this book. If Kenny were to comment on Shields' discussion of how actuality relates to motion and immobility – and therefore where is falls within physics and metaphysics – we might have a clearer idea of whether and how Kenny's philosophy may be unified and hierarchically ordered.

Even if left wanting for hierarchic order, both Kenny's philosophy and the essays featured in this volume bring to the fore several important topics in both contemporary philosophy and the history of philosophy. Some, such as David Charles' ‘Weakness and Impetuosity’, John Haldane's ‘Kenny and Aquinas on the Metaphysics of Mind’, and Joachim Schulte's ‘Some Remarks on “Wittgnstein's Early Philosophy of Mind”’, directly address Kenny's own positions and his interpretations of classic texts. Others, such as Jonathan Barnes' ‘The Opinion of Aristotle on Destiny’, Marleen Rozemond's ‘Descartes and the Immortality of the Soul’, and Severin Schroeder's ‘A Tale of Two Problems: Wittgentein's Discussion of Aspect Perception’, deal with issues of interest to Kenny, but not with Kenny's philosophy directly. The book is divided into four parts each comprising four chapters, and each part is dedicated to a figure of particular interest to Kenny: Aristotle, Aquinas, Descartes, and Wittgenstein.

Given the role it plays in Kenny's Aristotle on the Perfect Life (1993), the last chapter of Aristotle's Eudemian Ethics is the focus of Sarah Broadie's essay. The main question she poses regards the limit, the archê, to which the excellent person stands as ‘slave’ to ‘master’. Broadie explains that the ‘master’ is God and that the slave's ‘service’ is the contemplation (theôria) of God. Hence a natural good is ‘limited’ to the extent that it maximizes theôria in this present life. In the Eudemian Ethics, Aristotle is committed to the thesis that eudaimonia is activity in accord with the individual human virtues. Yet for Aristotle it is still possible for one to possess all the necessary virtues but lack ‘complete virtue’ (kalok'agathia). To be a truly good person one must possess natural goods not simply in the abstract, but as concrete ‘goods’ or ‘ends’; otherwise these goods simply make a bad life worse and detract their possessor from eudaimonia. Broadie explains that Aristotle taps into the ancient idea of the fragility of natural goodness. A person cannot attain complete virtue unless he also possesses a reflective attitude towards virtue. He must consciously deem the virtues and their associated activities as noble and regard them as essentially outranking natural goods.

Jonathan Barnes ponders the question of how an Aristotelian should tackle the issue of free will, especially in the face of hard determinism. He turns to Alexander of Aphrodisias, Aristotle's commentator, to contrast determinism with Aristotle's notion of ‘destiny’. Simply put, according to Alexander, destiny is a ‘productive cause’: a cause that gets something going. Destiny is something that comes about for the sake of something, even though it does not come about by the work of reason (like art), nor does it happen all the time. The fact that destiny can be classified as a productive cause illustrates the flexibility with which Aristotle understood ‘cause’. Indeed, my decisions and actions, though free, have their causes. It does not make sense for me to claim that I am forced to do something because I decide to do it, or that I am unable to do something because I do not want to do it. In short, if my decisions have causes, this does not mean that what I do is not up to me.

David Charles, turning to the relation between practical reasoning and incontinence, challenges the accepted interpretation of the latter. He argues that not all cases of acrasia boil down to mistakes in reasoning through Aristotle's famous moral syllogism, but that some cases of acrasia involve true conflict. Terence Irwin examines the role of consent in Aquinas' theory of action, arguing that Saint Thomas' ‘description of voluntary action gives us a paradigm rather than a general set of necessary and sufficient conditions’ (116).

Commending Kenny for the ‘broad and deep humanism’ that has influenced his philosophy of mind, John Haldane revisits the Thomistic theory of immaterial knowledge and Kenny's reasons for holding that the modern philosophy of mind repeats the errors of Cartesianism. Haldane admits that it was Kenny who helped him realize that the kind of existence involved in intentionality is predicational rather than substantial. Yet he also proposes some modifications to Kenny's theory. He suggests that when Kenny speaks of a power ‘abiding’ or ‘underlying’ actuality, we would do well to follow the general Aristotelian principle that potentialities are linked to actualities: in this case, the intellectual agent and the intellectual acts by which the power is exercised. In this way, we also supply the ‘interconnected individuation conditions’ that are needed to assert that any given thought is the one it is in virtue of its being a thought of A, about B, at time ‘t’.

David S. Oderberg teases out the merits of the first premise stated in Aquinas' first ‘way’ (i.e. ‘everything that is changing is being changed by something else’): a premise which Kenny resoundingly rejects. While acknowledging the difficulties involved in distinguishing between movement that is per se and per accidens, Oderberg argues against Kenny's suggestions that souls are mundane primary movers and that the premise implicitly holds that whatever is changing is being deterministically changed by another. According to Oderberg, Kenny gives short shrift to Aquinas' idea that change is a reduction of something from potentiality to actuality. The idea simply requires that the change of anything from being potentially F to actually F requires some distinct actuality to bring about that change. ‘The very idea that a mere potentiality – that which does not itself actually exist – could make the transition to actuality without the concurrent causal activity of something actual that is distinct from the potentiality should strike one as absurd, as it struck Aquinas and Aristotle’ (162). In arguing that the first premise of Aquinas' first way is ‘plausible, defensible, and immune to the many and by now famous criticisms fired at it by Kenny’ (163–4), Oderberg, like Shields, alludes to why it may be difficult to hierarchically order and unify Kenny's philosophy.

Brian Davies examines the action of God by focusing on what Aquinas means when he says that certain things ‘have esse’. What Aquinas partially means is that a thing has esse if it actually exists, and especially if it exists as the substance it actually is. Thus artefacts, postmen, and blindness are not substances and do not ‘have esse’. At the same time, Aquinas does not think that something that has esse is ‘descriptively different’ from that which has esse. In short, ‘existence … is indefinable; there are no simpler notions which we can bring together in order to get someone to see what it is for something simply to exist’ (174). Davies concludes that for Aquinas, the esse of things does not necessarily imply the existence of God. In other words, the esse of things does not require us to hold that the universe must have had a beginning and that God must be invoked to account for the existence of the universe. Davies does think, however, that Aquinas implies that the existence of the universe raises the question ‘why is there something rather than nothing?’.

One of Kenny's main projects has been to situate Descartes properly within the intellectual climate of his time. Kenny's study has led him to conclude that ‘when Descartes tells us that something is taught by the natural light in our souls, he produces a doctrine taught by the Jesuits at La Flèche’ (209). Perhaps Descartes' Jesuit education underlies his initial assumption that there is distinction between physics and metaphysics, and that God and the soul pertain to the latter. Desmond M. Clarke explains that the great differences between appearance and reality eventually led Descartes to believe that there is no clear method for distinguishing between physical and metaphysical realities. Descartes went on to apply the distinction between appearance and reality not only to objects of sensory perception, but to objects of all types of thinking. Clarke reads Descartes' dualism as ‘an impasse in his efforts to construct a meaningful explanation of the experience of thinking’ (206). Because Descartes was trying to formulate a philosophy that would be compatible with his Roman Catholic theology, his arguments for a real distinction of mind and body and for the existence of God ‘were spectacularly unsuccessful’ (206).

Stephen Gaukroger draws an interesting connection between Descartes' notion of perceptual cognition and morality. He laments that Descartes is commonly viewed only as a revolutionary cognitive theorist. Yet Descartes was trying to do much more than simply establish cognitive contact with the physical world (his corporeal cognitive processes were sufficient for that). Diderot, Gaukroger explains, criticized Descartes for a purely intellectual constitution of the subject that results in a morally stunted, solipsistic creature closed within a world of his own rather than in the real moral world. In the end, moral theory does not disappear during this period of history, but ‘rather that it takes a form very different from that which we find in Plato, Aristotle, Kant, or Mill’ (251). In short, philosophy at the time of Descartes was more concerned about the shaping of the moral persona than with identifying virtues for prescribing conduct.

Marleen Rozemond revisits Descartes' arguments for the immortality of the soul, showing that he did not rely primarily on the notion of simplicity as a way of establishing the soul's immateriality. When Descartes focuses on the mind's simplicity, he is more concerned with the interaction and unity of mind and body rather than the soul's intrinsic nature. He never claims to have proved that the soul is immortal, but rather sketches how he might establish the soul's immortality. Rozemond believes that Cartesian scholarship has failed to focus on the historical background of two Catholic ideas that have had a lasting influence on Descartes: (1) that the soul can exist without the body, and (2) that it is incomplete without the body. She points to Kenny as someone who has studied Descartes with the requisite knowledge of Aristotelian scholasticism to tease out how it influenced Descartes' rejection of traditional hylomorphism.

Kenny encountered Wittgenstein's philosophy primarily through his teacher Elizabeth Anscombe. It was Wittgenstein who formed Kenny's ideas about the goals and limits of philosophy. Philosophy aims at a distinctive form of understanding based on the conceptual forms and structures that we use to articulate our knowledge of the world, ourselves, and the values we hold. Hans-Johann Glock compares the objectivist or logical conceptions of knowledge, according to which concepts exist independently of individual human minds (i.e. ‘self-subsistent abstract entities or abstractions from linguistic practices’, 307); and subjectivist or psychological conceptions (i.e. as mental phenomena, entities or goings-on in the minds of individuals). Glock argues that concepts are neither mental particulars, as subjectivism says, nor properties or meanings, as the objectivists maintain. This clears space for an indirect approach to concepts by means of other questions. Glock views the possession of concepts as an ability and rejects Wittgenstein's proposal that concepts themselves can be equated with abilities. Concepts are objective in the sense that they exist independently of individual minds, and subjective in the sense that this existence derives from the cognitive capacities and achievements of rational creatures.

For as interesting as each of the sixteen essays is individually, none of them offers an overall appraisal of Kenny's philosophy. Perhaps Haldane's comes closest. Those of Shields, Davies, and Oderberg notably touch upon the metaphysical principles that have the potential to impart unity to philosophy and arrange it into some hierarchic order. Yet I am not convinced that Kenny himself uses those metaphysical principles in a way that would impart unity and structure to his own philosophy. To take but one example, Kenny interprets Aquinas to teach that ‘the esse that is identical with God is the esse that is common to all entities’ (Aquinas on Being, 188). Not only is this a misreading of Aquinas, it also enervates the analogia entis of its explanatory power. The ratio of the unity of esse consists not in univocation but analogy. Aquinas argues that esse in God is ‘universally’, whereas in creatures it is ‘particularly’. As an analytic philosopher, it seems that Kenny understands ‘universally’ in a predicatory sense, whereas what Aquinas really has in mind is causation. God is esse itself because he is the universal cause of esse, not because he is the highest possessor of esse. How the notion of God as the universal cause of existence relates to faith and reason is well beyond the scope of this review and the individual essays it has reviewed hitherto. Yet however we arrive at it, the notion of God as the universal cause of existence seems to be the key to any successful recapitulation of the history of philosophy.