Grenberg has accomplished the seemingly impossible. She has written an entire book on Kant's take on our pre-theoretical conception of morality, and the ordinary agent, without discussing Rousseau, or Kant's Rousseauian turn.Footnote ¹ One might regard this as a weakness of Grenberg's book. I, however, think it is a merit, since much has been written specifically on Kant and Rousseau already. Grenberg focuses exclusively on a detailed reconstruction of Kant's position and arguments in the Groundwork and the second Critique. Kant's Defense of Common Moral Experience is a focused, analytic, original and illuminating study of the role of ordinary moral experience for Kant's practical philosophy.

In part 1, Grenberg introduces the special phenomenological method that she attributes to Kant: ‘to engage in practical philosophy, Kantian style … we must set aside third person, theoretical concerns and enter first into phenomenological reflection upon the common, first-personal experience of ourselves as agents’ (15). First-personal, felt experiences are not idiosyncratic but express ‘universally shared aspects of our agential experience’ (21). Both the common agent as well as the philosopher should pay attention to their phenomenological experience, and become better at understanding how the moral law forces itself upon us. Becoming moral and becoming a moral philosopher begin with the same attentiveness to this experience of obligation.

We cannot know the cause of our phenomenological experiences. Yet these experiences can be ‘hints of something intelligible’ (196), and the cause of these experiences can be an object of wonder and mystery for us. Attentive reflection on phenomenological felt experiences makes ‘more and more clear to oneself … the exact nature of that experience’ (55). Feeling is not the grounding of moral obligation, but the epistemic tool that gives us epistemic access to the thing ‘that will provide evidence or proof of practical cognitions’ (59), namely to our rational nature. The feeling Grenberg is describing is of course respect: a sensible, a priori feeling of being categorically obligated.

In part 2, Grenberg turns to a detailed investigation of the role of first-personal phenomenological experience in the Groundwork. According to Grenberg, the Groundwork distinguishes between a pre-corrupted and a corrupted state of agency. In the pre-corrupted state the common agent can appreciate categorical obligation, and a Socratic guide can help and encourage her to be more attentive to her moral experience, but does not have to provide any new or philosophical ideas. Kant's treatment of the natural dialectic at 4: 405 describes the common agent's exit from her state of innocence. From Groundwork II onwards Kant rejects a phenomenological experience of categorical obligation, since the possibility of self-deception discredits our seeming experience of moral or categorical obligation. The cure for the corrupted common agent is not a ‘more intensive appeal to the common person herself’ (94), but comes from the academic philosopher, and is ‘asking us to exit the common point of view’ (90).

Due to his rejection of the possibility of a reliable experience of categorical obligation, Kant's Groundwork III deduction draws on the phenomenological experience of negative freedom, or of being ‘simply unconstrained’ (114). According to Grenberg, attentive reflection upon the experience of negative freedom cannot vindicate our status as moral agents without the additional, theoretical premise that ‘in the world of sensibility, everything is caused by something else’ (128). Groundwork III is a phenomenological failure because Kant is not willing to simply accept an experience of categorical obligation as the starting point for his deduction.

It should be noted that Grenberg's criticism of Kant's Groundwork III deduction can either be understood as revealing a weakness in Kant, or alternatively point to limits of Grenberg's own phenomenological interpretation. Grenberg assumes that being morally obligated can only be vindicated in a purely phenomenological manner, and she turns this against Kant's argument, instead of against her phenomenological interpretation. I do not see why the Groundwork deduction as one of the most complex philosophical operations in Kant's work cannot combine different approaches, phenomenology as well as theoretical or metaphysical enquiry into the structure of appearances and rationality. Grenberg largely ignores the opportunity to constructively enrich her account of Kant's methodology with elements from the theoretical sphere such as propositions about the causal determinism of appearances grounded in the first Critique.

In part 3, Grenberg turns to the supposedly more phenomenological second Critique, and especially to the fact of reason. Kant, according to Grenberg, ‘turns himself around 180 degrees’ (160) in the second Critique, and relies on phenomenological experience of obligation, instead of on experience of negative freedom. In the second Critique, Kant is optimistic that the method of attentiveness to one's experience can reveal unconditional obligation even to the corrupted agent. The Second Gallows Case (5: 30) is the prime example of a phenomenological experience of a ‘constraint of inclinations by this special feeling of respect’ (166).Footnote ² Attentiveness to this experience lets philosophers recognize the two central claims inherent in the fact of reason, namely that: (i) rational human agents are categorically obligated by the moral law, and (ii) they are capable of acting as the moral law demands – (i) leads to the formulations of the categorical imperative, (ii) is the basis for the deduction of freedom.

In her last chapter, Grenberg discusses how to respond to people who claim to lack a phenomenological experience of obligation. According to Grenberg, respect is an objective, synthetic a priori practical cognition, or an ‘intersubjectively valid experience’ (278), since all rational human beings share it. Grenberg's argument here amounts to the orthodox Kantian position that respect is a special, rational and necessary feeling. She does not establish, nor does she intend to establish, the objectivity of moral cognition for someone who does not already buy into Kantian premises. According to Grenberg, an agent who ‘stubbornly asserts’ that she lacks the relevant experience should be told ‘to pay more attention!’ (281).

Grenberg's reading of Kant is innovative and thought-provoking in a number of ways, three of which I would like to point out and briefly discuss. (i) Grenberg stresses that phenomenological or felt experience is epistemically potent and crucial for Kant's practical philosophy. However, some of the major passages pertaining to the role of feeling in Kant suggest, I think, that the Groundwork might not be a phenomenological failure, but simply not a work that hinges on phenomenology in Grenberg's sense. Instead, in the Groundwork, especially Groundwork I, Kant is interested in how agents without philosophical education judge about certain concrete cases of moral relevance, what criteria are exhibited in these judgements, how these criteria figure in ordinary reasoning and what principles or metaphysical positions these agents implicitly commit themselves to in their reasoning. This stress on judgement and ordinary reasoning, as opposed to feeling, can also be found in later works.Footnote ³

(ii) According to Grenberg, we do not have an awareness of moral obligation prior to the feeling of respect.Footnote ⁴ The feeling of respect coincides with our consciousness of being under moral obligation. Respect informs us that we are obligated, what we are obligated to do, and it can motivate us to act (140–8). This conception of the fact of reason and respect presents the pre-theoretical agent as passive and receptive. Grenberg regards it as one of the advantages of the second Critique over the Groundwork that in the second Critique Kant solely relies on a passive feeling of moral obligation. This conception ignores that the Groundwork and second Critique both emphasize common agents’ active engagement with moral subject-matters. Kant is aware that an autonomous agent is not simply provided with moral knowledge by a feeling, but has the ability to determine on her own what ought to be done by actively reflecting about moral situations (see the passages in n. 3, below). What room does Grenberg's account leave for the crucial moment of actively reasoning about what ought to be done in the light of rational criteria such as universality and dignity? Respect does too much work on Grenberg's interpretation and threatens to eclipse a very common part of our moral experience: the experience of reasoning, reflecting, weighing reasons and finally arriving at a conclusion regarding what to do.

(iii) Grenberg's account emphasizes the self-sufficiency of the rational agent, and she only spends half a page discussing the role of education for Kant (282). It would be interesting to see if Grenberg's account can be expanded to give as much weight to moral education, and the role of a moral community as Kant seems to give it in his Doctrines of Method in the second Critique and Metaphysics of Morals.

According to Grenberg, it is the ‘tragedy of Kant scholarship in the past 200 years’ to have lost sight of Kant's ‘first intention of his project – the defence of a common approach to ethics’ (1). Grenberg's book is part of a growing trend of approaching Kant from his commitment to our ordinary reasoning, or ordinary understanding and experience of morality. Grenberg's views are, even when outside of the mainstream, forcefully argued with great knowledge and understanding of Kant's practical (and theoretical) philosophy, and brought forward with the intention of presenting a systematically attractive interpretation that challenges the received understanding of Kant as well as of how to approach moral philosophy.