Like several prominent moral philosophers before him, such as St Augustine and St Thomas Aquinas, Kant held that it is never morally permissible to tell a lie. Although a great deal has been written on why and how he argued for this conclusion, comparatively little has been written on what, precisely, Kant considered a lie to be, and on how he differentiated between being truthful and being candid, between telling a lie and being reticent, and between telling a lie and other forms of linguistic deception. That is to say, very little has been written on the scope of Kant's prohibition against lying. In this article I will argue that the scope of the prohibition against lying is narrower than it is commonly supposed to be.

We discuss Kant’s conception of moral rationalism from the viewpoint of recent debates, which have distinguished different forms of moral rationalism. We argue that Kant’s version, ‘silencing’, is different and stronger than currently held versions of moral rationalism and that it also differs from versions of silencing that contemporary thinkers advocate. We then discuss Kant’s version of silencing in the context of the moral demandingness debate and argue that silencing can make a perfect duty very demanding. However, it is important that whilst in cases of conflict between duty and personal happiness the normative standing of the latter is silenced, silencing does not require that agents do all they can in the case of imperfect duties. We finally indicate the kind of latitude imperfect duties allow for, according to Kant’s strong form of moral rationalism.

Kant has long been known for denying that emotions constitute an adequate basis for morality or for moral motivation. But Kantian ethicists have recently been calling attention to Kant's recognition of the moral importance of emotions. Several philosophers have pointed out that, for example, Kant sees emotions as indicators of appropriate or inappropriate attitudes and as means of prompting us to perform particular morally right actions. In chapter 6 (p. 207) of Kantian Ethics Almost without Apology, however, Marcia Baron points out a passage in the Metaphysics of Morals that sits poorly with these recent, emotion-friendly interpretations of Kant.

Few of Kant's doctrines are as difficult to understand as that of self-affection. Its brief career in the published literature consists principally in its unheralded introduction in the Transcendental Aesthetic and unexpected reappearance at a key moment in the Deduction chapter in the second (B) edition of the first Critique. After blazing its trail, self-affection retreats into the background, with a discussion befitting its importance occurring only in the unfinished Opus postumum. This step out of the limelight, however, belies the doctrine's continued importance for Kant; indeed, Kant seemed to think that in self-affection was to be found the key to the project that occupied him in his last years. Thus, ‘the possibility of the transition from the metaphysical foundations of natural science to physics does not consist in the fact that the subject is empirically affected but rather that it affects itself’ (Opus postumum, 22: 405). As he continued to struggle with this doctrine and with the pivot-point on which to work this vital transition, Kant himself would surely come to rue his confident statement in the B Deduction: ‘I do not see how one can find so many difficulties in the fact that inner sense is affected by ourselves’ (B156n).

It has been argued that Kant’s practical philosophy cannot allow for degrees of responsibility for one’s actions. However, it would be uncompromising to allow for only two possibilities: either full responsibility or none. Moreover, in the Metaphysics of Morals Kant himself claims that there can be degrees of responsibility, depending on the magnitude of the obstacles that have to be overcome when acting. I will show that this claim is consistent with Kant’s theory as a whole and thereby make transparent how degrees of responsibility are possible for Kant. The solution is based on the distinction between two senses of responsibility: taking oneself to be an accountable person is an all-or-nothing affair, whereas praise- or blameworthiness for a particular action can still be a matter of degree.

In the interpretation of Kant’s transcendental idealism, a textual stalemate between two camps has evolved: two-world interpretations regard things in themselves and appearances as two numerically distinct entities, whereas two-aspect interpretations take this distinction as one between two aspects of the same thing. I try to develop an account which can overcome this dispute. On the one hand, things in themselves are numerically distinct from appearances, but on the other hand, things in themselves can be regarded as they exist in themselves and as they appear. This reveals a mutual entailment of both accounts. Finally, I suggest that this approach most naturally leads to a kind of ‘phenomenalism’, but of a sort not normally attributed to Kant.

One striking contrast that Kant draws between the kind of cognitive capacities that humans have and alternative kinds of intellect concerns modal concepts. Whilst ‘it is absolutely necessary for the human understanding to distinguish between the possibility and the actuality of things’ (5: 401), the very distinction between possibility and actuality would not arise for an intuitive understanding. The aim of this paper is to explore in more detail how the functioning of these cognitive capacities relates to modal concepts, and to provide a model of the intuitive understanding, in order to draw some general lessons for our ability to make modal judgements, and the function of such judgements.

The debate regarding the interpretation of Kant's idealism is usually seen as turning on the best way to understand his transcendental distinction between appearances and things in themselves: that it marks either a contrast between two types of thing (the ‘two-object’ or ‘two-world’ view) or one between two sides or aspects of ordinary empirical objects (the ‘two-aspect’ view). But, even though I have long been associated with the latter camp, I have also thought for many years that this is not the most helpful way to frame the issue. The problem lies in an ambiguity inherent in the two-aspect view. It can be understood either metaphysically, as a thesis about the kinds of properties attributable to empirical objects, that is, as a form of property dualism in which these objects are assigned both phenomenal and noumenal properties, or methodologically, as a contrast between two ways in which such objects can be considered in a philosophical reflection on the conditions of their cognition. Accordingly, I take the fundamental question to be whether transcendental idealism is to be understood in the latter way or as a form of metaphysical dualism (whether as a thing or a property dualism being a matter of relative indifference). And I have further thought that the best way of addressing that question is through a consideration of the view which Kant opposes to transcendental idealism, namely, transcendental realism. If this realism is identified with a particular metaphysical doctrine then transcendental idealism must be as well; but if, as I maintain, transcendental realism cannot be so understood, then neither can Kant's idealism.

This paper focuses on a single question that highlights some of the most puzzling aspects of Kant’s explanation of the duty of moral self-perfection. What kinds of activity count as striving for purity in one’s disposition to duty, or strength of will? I argue that a dominant strand of Kant’s approach to moral striving does not fit familiar models of striving. I seek to address this problem in a way that avoids the flaws of synchronic and atomistic approaches to moral self-discipline by developing an account of Kantian moral striving as an ongoing contemplative activity complexly engaged with multiple forms of self-knowledge.

Little extended attention has been given to Kant’s notion of self-conceit (Eigendünkel), though it appears throughout his theoretical and practical philosophy. Authors who discuss self-conceit often describe it as a kind of imperiousness or arrogance in which the conceited agent seeks to impose selfish principles upon others, or sees others as worthless. I argue that these features of self-conceit are symptoms of a deeper and more thoroughgoing failure. Self-conceit is best described as the tendency to insist upon one’s own theoretical or practical conclusions at any cost, while still wanting to appear – to oneself or to others – as though one is abiding by the constraints of theoretical or practical reason. Self-conceit is thus less centrally the tendency to impose one’s will or inclinations upon others, and more centrally the tendency to reconstruct evidence and rationalize so that one may be convinced of one’s own virtue. While the conceited agent may ultimately impose her judgement upon others, she does so in order to preserve her delusion of virtue.

Kant’s account of practical justification for belief has attracted much attention in the literature, especially in recent years. In this context, scholars have generally emphasized the originality of Kant’s thought about belief (Glaube), and Kant indeed offers a definition of belief that is very different from views that were prevalent in eighteenth-century Germany. In this article, however, I argue that it is very likely that Christian August Crusius exerted influence on Kant’s definition of belief and his account of practical justification. In turn, acknowledging this influence has relevant consequences for how we understand the phenomenology of Kantian belief.

In his later moral writings Kant claims that we have a duty to cultivate certain aspects of our sensuous nature. This claim is surprising for three reasons. First, given Kant's ‘incorporation thesis’ – which states that the only sensible states capable of determining our actions are those that we willingly introduce and integrate into our maxims – it would seem that the content of our inclinations is morally irrelevant. Second, the exclusivity between the passivity that is characteristic of sensibility and the spontaneous quality of our free will that operates throughout Kant's philosophy seems to preclude that any such cultivation is possible. Third, Kant's specific arguments concerning why we are obliged to cultivate our sensible nature are unclear. The goal of this paper is to address each of these three concerns and thus fully explain Kant's theory of the moral necessity of cultivation.

This article analyses the teleological argument justifying historical progress in Kant's Guarantee of Perpetual Peace. It starts by examining the controversies produced by Kant's claim that the teleology of nature supports the idea of a providential development of humanity towards moral progress and the possibility of achieving a cosmopolitan political constitution. It further illustrates how Kant's teleological argument in Perpetual Peace needs to be assessed with reference to two systematically relevant issues: first, the problem of coordination linked to the necessity of realizing the ‘highest good’ as a historical end of practical reason, and secondly the problem of continuity posed by the temporal limitation of all individual efforts to cultivate moral dispositions. To illustrate the implications of both issues for the teleological argument in Perpetual Peace, the article draws attention to some important developments in Kant's analysis of teleology following the Critique of Judgment.

Kant conceives of moral agents as autonomous, capable of motivating themselves to act on a self-given rule of reason, independently of – and even against – their inclinations. Moreover, Kant's moral theory tells agents to realize their autonomy, by striving to do what is right for its own sake. It is because of Kant's emphasis on autonomy that his notion of the highest good has been a topic of controversy. From Kant's time onward, commentators have suspected that the highest good, which promises virtuous agents happiness proportionate to their goodness, introduces heteronomy into morality. The standard response to this concern is that critics have misunderstood the relationship of the highest good to the agent's will: it is an object, not a spring, of moral action. This is a valid response to some articulations of the objection. But it does not adequately address the version that interests me: the charge that belief in God as the guarantor of happiness proportionate to virtue plays an inappropriate motivational role in Kant's moral theory. Kant appears to say that without belief in a God who will make the virtuous happy we would not be motivated to act rightly. This sort of claim seems to conflict with Kant's notion of moral agents as beings who are capable of doing the right thing just because it is right. If this conflict cannot be resolved, Kantians face a dilemma: either weaken the notion of autonomy, or (more likely) weaken the claims about the moral importance of faith in God.

Attitudes like shame and contempt seem to be at odds with basic tenets of Kantian moral theory. I argue on the contrary that both attitudes play a central role in Kantian morality. Shame and contempt are attitudes that protect our love of honour, or the esteem we have for ourselves as moral persons. The question arises: how are these attitudes compatible with Kant's claim that all persons deserve respect? I argue that the proper object of shame and contempt is not the humanity within a person, but rather her self-conceit, or the false esteem that competes with love of honour.

This article advances a new account of Kant’s views on conceptualism. On the one hand, I argue that Kant was a nonconceptualist. On the other hand, my approach accommodates many motivations underlying the conceptualist reading of his work: for example, it is fully compatible with the success of the Transcendental Deduction. I motivate my view by providing a new analysis of both Kant’s theory of perception and of the role of categorical synthesis: I look in particular at the categories of quantity. Locating my interpretation in relation to recent research by Allais, Ginsborg, Tolley and others, I argue that it offers an attractive compromise on this important theoretical and exegetical issue.

All duties are either duties of right (officia iuris), that is, duties for which external lawgiving is possible, or duties of virtue (officia virtutis s. ethica), for which external lawgiving is not possible. - Duties of virtue cannot be subject to external lawgiving simply because they have to do with an end which (or the having of which) is also a duty. No external lawgiving can bring about someone's setting an end for himself (because this is an internal act of the mind), although it may prescribe external actions that lead to an end without the subject making it his end. (Immanuel Kant, The Metaphysics of Morals)

Schopenhauer presents his moral philosophy as diametrically opposed to that of Kant: for him, pure practical reason is an illusion and morality can arise only from the feeling of compassion, while for Kant it cannot be based on such a feeling and can be based only on pure practical reason. But the difference is not as great as Schopenhauer makes it seem, because for him compassion is supposed to arise from metaphysical insight into the unity of all being, thus from pure if theoretical reason, while for Kant pure practical reason works only by effecting a feeling of respect (in the ‘Critical’ works) or by cultivating, i.e. affecting, natural dispositions to moral feeling (in the ‘post-Critical’ works). I argue that Kant's is the more realistic theory on this point.