A new collection of essays by one of the world’s leading Kant scholars is an event to be welcomed and this collection is no exception. Guyer offers a three-part division to his central theme, beginning with six essays on The Value of Freedom, followed by four on The Actuality of Freedom and, finally, a further four essays on The Achievement of Freedom. As a leitmotif running through the collection, freedom offers a unifying theme, but the topics covered are wide-ranging and there is something said about most areas of Kant’s practical philosophy. Overall, this adds up to a provocative and readable collection that will offer something to almost anyone with an interest in Kant’s philosophical project.

Guyer sets the stage in the preface, by defining virtue in two senses. The first is as ‘a particular form of moral excellence … [that is] any of certain moral qualities regarded as of particular worth or importance’. The second is as ‘conformity of life and conduct with moral principles; voluntary adherence to recognised laws or to standards of right conduct’ (p. v). This is straightforward and Guyer will adhere to the idea that freedom, as the fundamental virtue in the first of these senses, is an achievement to be attained and maintained. In the first definition of virtue, there is some contrast with Kant’s definition of virtue as a moral strength of a human being’s will in fulfilling his duty, a moral constraint through his own lawgiving reason insofar as this constitutes itself an authority executing the law (MM, 6: 380, 394, 405).

Guyer’s belief that freedom is the fundamental virtue in the first of these senses is maintained throughout the book. This might be contrasted with freedom in the sense of a metaphysical condition or ability to choose between two alternative courses of action, no matter what one’s prior history would seem to entail that one will do. In this sense, freedom, he claims, is dependent on Kant’s transcendental idealism, a doctrine about which Guyer is known to have considerable reservations. Just how far we are free to preserve and promote freedom is an empirical question. In the light of the totality of Kant’s writings on moral philosophy, Guyer opts to separate the discussion of the virtue of freedom, as defined above, from the age-old question of freedom of the will. The good will may be the only thing that could be considered good without limitation (G, 4: 393) but it requires freedom, as the ‘only thing of intrinsic and unconditional value’, for its exercise. Reason is not the same thing as freedom but is required in order to maximize the intra- and extra-personal use of freedom. Reason is therefore ‘first among things of instrumental value’, though this does not imply that some sort of consequential or utilitarian rationale is being attributed to freedom.

The chapter titled Introduction is in fact an essay on ‘Kant, Autonomy and Modernity’ (one of three chapters not previously published). Autonomy is Kant’s Big Idea: the concept that is truly modern, a view he summed up at the end of his critical philosophy (CPJ, 5: 196). This is an appropriate place to start: the place of autonomy, both authentically understood and misunderstood, is surely Kant’s most lasting gift to moral thought with huge implications for individuals, communities, society, public policy and Western culture (indeed, I am tempted to say, for world culture). Guyer wants to argue that there is something new and modern about this; and that autonomy is a universal value. In pursuing this aim, he describes ancient aspects of autonomy in a short but invaluable summary, not easily found elsewhere. This leads to a view of Kantian freedom as positive. The end in itself owes its status not to reason but to ‘freedom, only freedom alone’ (L-NR, 27: 1321–2). Guyer adeptly leads us to Kant’s new conception of autonomy because an end in itself cannot be treated as a mere means and is the capacity to set ends itself.

In the second chapter, Guyer relates Hume’s derivation of morality through grounding moral principles in how we are: an ought from an is. He interprets Kant in the Groundwork as taking a related position in deriving ought from our rational nature, while modifying this in the second Critique and making a more firm statement in the Religion. The argument of the chapter starts from refining the conventional view of Hume in stating that Hume’s ought is derived from the ‘right sort’ of is, i.e. an empirical description of our moral sentiments. He then contrasts Kant who insists that the fundamental property of morality must be grounded in our reason and not our sentiments. From there he argues that normative principles must stand on their own, independent of any descriptive statements. Finally these conclusions are applied to modern meta-ethics. Orthodox teaching in philosophy has emphasized for many years the importance of distinguishing the world of nature from the world of values and stressed Kant’s role in teaching this. Guyer is challenging our simplistic thinking and, for those of us raised on the notion that an ought cannot be derived from an is, he offers a novel insight.

Guyer makes a number of observations on Kant’s early work: his chapter 3, for example, is devoted to a discussion of foundations, starting with the 1762 distinction between problematic and legal necessity as the forerunner of that between hypothetical and categorical imperatives. The links to Wolff and Baumgarten are clearly apparent. Within two years (by 1764) Kant had arrived at an approximation of his mature formulation of the categorical imperative. The relevance of this to freedom is to connect it with universalizability. Kant’s early notes on ethics put beyond doubt, says Guyer, that the absolute value of freedom is the supreme principium of Kantian ethics (p. 44). As an insightful exploration of the development of a key principle, this chapter offers much more than an exercise in Kantian archaeology.

A similar look at Kant’s antecedents comes in a chapter on Kantian perfectionism (chapter 5). This makes a valuable contribution to discussions of virtue ethics with the conclusion that ‘perhaps Kant should be regarded as the best model for an ethics of virtue’ (p. 86). The chapter includes a superbly clear comparison of Wolff’s perfectionism, with discussion along the way of Wolff’s thinking in relation to Aristotle, a short exposition on Mendelssohn and a comment on the highest good. Kant, according to the quotes that Guyer supplies, thinks that it is impossible to do more than our duty – a viewpoint familiar from the work of Baron (Reference Baron1987). Both Guyer and Baron reject any place for a concept of supererogation in Kant, in contrast with the views of Hill (Reference Hill1971) or O’Neill (Reference O’Neill2013), for example. This has long been one of those minor bones of contention. Is it possible to accommodate supererogation within a system of principles, in which duty appears to govern all? Space does not permit pursuing this debate further here, but this contribution advances the dialectic. I found this particular chapter especially clear and enjoyable, in linking Kantian thought with Aristotle and bridging a gap between deontological and virtue ethics.

How does freedom relate to the essential ends of humankind? Guyer points out (in chapter 4) that the phrase ‘essential ends of humankind’ occurs only twice in his main works (one of which is ‘quite obscure’) and chiefly features in his lectures. He will argue that for Kant the essential end of humankind can only be one that makes one’s own happiness mediate as a part of a universal happiness. But lest this should lull the unsuspecting reader, Guyer points out that the essential end of mankind is not the same as the highest or complete end, which directs us to the discussion in the second Critique (at 5: 110). Back to the lectures, Kant describes freedom in accordance with a rule as the essential end of mankind and the perfection of free choice as inner goodness. Freedom to set our own ends is the only thing of unconditional and intrinsic worth. The chapter (re)introduces the ideas of negative and positive freedom; and, of course, the paradoxical idea that adherence to law is how freedom is exercised.

The chapters in part II (The Actuality of Freedom) focus on Kant’s struggle with free will. Thus, although the initial chapter 8 starts with Kant’s attempt to prove the validity of the moral law, it approaches this by proving that we have free will and that the moral law is the only possible law of a free will. The distinction between the analytic method of the first two sections of the Groundwork and the synthetic method of the third section is considered in terms of ostensive rather than apagogic methods (an apagogic method proceeds by disproving the proposition that contradicts the one to be established). In a chapter on moral feeling (chapter 14), Guyer introduces debate around ‘respect’ as a self-wrought feeling different from others. Guyer argues that feeling does play an essential causal role at least in the phenomenal aetiology of morally worthy action. This he will relate to the cultivation of moral feelings such as sympathy in the late Doctrine of Virtue. Although the relation is inscrutable, Kant must separate the noumenal will to follow the moral law from the phenomenal process of willing a particular action. The lectures provide an early view on moral feeling, but Kant nonetheless denies the capacity of abstract morality to impel an agent to action without an effect on the human ‘heart’. Guyer tracks the changes in Kant’s views as he proceeds through the Groundwork to the Metaphysics of Morals.

The final chapter (16) concerns ‘Kantian communities’. This brings together the realm of ends, the moral world, the ethical community and the highest good. The latter concept undoubtedly changes over time and Guyer plots this into the 1790s, including an account of the highest good and the highest political good. Although the highest good has been much discussed by Kant scholars, this chapter is a beautifully written summary, serving to put the highest good in the context of the realm of ends and the moral world. Rather than arguing for an interpretation requiring a deity or pursuing an entirely secular viewpoint, Guyer sets this out as developmental: a key concept in which Kant’s thought matured from the Groundwork through to the Opus Postumum.

I have selected a few of the sixteen essays for brief comment, but that hardly does justice to the breadth and interest of this collection. This is a treasure trove of essays on Kant’s moral philosophy that will be read and valued for years to come. It is recommended with enthusiasm.