Kant ' s account of moral weakness

On the one hand, Kant seems to suggest that moral weakness is merely expressed at the level of following maxims. On the other hand, he addresses moral weakness as the first grade of our propensity to evil, which implies that moral weakness is also expressed at the level of adopting maxims. There is still a lack of clarity in the literature concerning how the relationship between these two aspects is to be understood, and a proper account of the nature of the maxims of the morally weak has yet to be offered. Drawing on myearlier interpretation of moral strength, I shall propose a reading of Kant's account of moral weakness that consistently unifies both aspects. On my interpretation, the morally weak agent lacks the moral strength that he ought to acquire through the continuous exercise of his power of self ‐ control; he therefore fails both to set himself particular moral ends in adopting his maxims and to follow his maxims by realizing such ends. His intention to do what the moral law demands is overly general: It does not set a particular moral end, which is what virtue requires.

The puzzle of how to understand weakness of will in Kant's theoretical framework has often been formulated in relation to Henry Allison's incorporation thesis. According to the incorporation thesis, "an inclination or desire does not of itself constitute a reason for acting" because it becomes such a reason only when we incorporate it into one of our maxims (Allison, 1990, p. 40). The prevailing concern is that this thesis cannot be reconciled with what we usually call weakness of will. 2 As Marcia Baron (1993, p. 433) nicely explains, failure "to do something which one believes is morally required" cannot be said to happen simply because "the agent is overpowered by desire." 3 The incorporation thesis seems to make acting against one's better judgment impossible; weakness, as a failure to act in accordance with an adopted maxim, would seem to be based on yet another maxim, which again presupposes the incorporation of incentives. To the extent that the incorporation thesis holds, weakness would therefore seem to involve acting in accordance with an adopted maxim; the weak-willed agent does not so much act against her better judgment as change her mind.
And yet, interpretations of Kant's notion of moral weakness as a kind of weakness that is not expressed at the level of the incorporation of incentives fall prey to the difficulty of explaining why Kant thought that the morally weak heart is a manifestation of our propensity to evil. 4 As the first stage of our propensity to evil, moral weakness must involve some sort of improper incorporation of incentives into our maxims. As a result, we cannot fully capture Kant's understanding of the morally weak heart if we focus merely on the agent's failure to follow his established maxims; we must also determine what goes wrong at the level of maxim adoption in the case of the morally weak. 5 As I explained in Section 2, there is still ambiguity surrounding the relationship between the weakness exhibited at the level of maxim following and that exhibited at the level of maxim adoption. Furthermore, a satisfying account of the nature of the maxims of the morally weak has yet to be offered.
Over the past two decades, Kant's account of moral weakness has received increased attention, and scholars have come up with a variety of creative solutions. 6 Timmons (1994) and Johnson (1998), for example, employ the conceptual distinction between motivating and justifying reasons for action. Sussman (2001) uses Kant's treatment of the passions to account for weakness. Frierson (2014), for his part, specifies weakness as a defect of volition that is opposed to affects and passions. Strikingly, however, very few (if any) of the available accounts are based on Kant's notion of moral strength, in which virtue consists. 7 In any event, Kantian weakness of will has yet to be fully elucidated as lack of moral strength.
In Section 3, I propose a new reading of Kant's account of moral weakness by approaching moral weakness as a mere lack of moral strength. In this discussion, I draw on my twofold account of Kant's conception of moral strength (Vujošević, 2017), according to which moral strength, understood as a proper exercise of the capacity for self-control, is a necessary condition not only of acting in accordance with one's established moral maxims but also of adopting these maxims in the first place. That is, moral strength is required at the level of setting ourselves moral ends-not just realizing them. Here, I first describe the sense in which the morally weak agent lacks moral strength with regard to compelling himself to realize moral ends. I then provide a detailed analysis of the sense in which the morally weak agent lacks moral strength with regard to compelling himself to set himself moral ends. Put differently, I determine what goes wrong at the level of maxim adoption with the morally weak agent: The subjective motivating ground of his maxims remains impotent in practice because he fails to properly exercise his capacity for self-control in new situations. 8 This approach to Kant's conception of moral weakness has certain advantages. First, it highlights important aspects of moral weakness that have been overlooked thus far. Second, by accommodating the fact that Kant treats moral weakness as a stage of evil and by indicating how weakness is expressed at the levels of maxim adoption and action, this approach enables us to consistently unify the aspects of moral weakness that Kant articulates. Third, by addressing the neglected connections between weakness, moral strength, moral feeling, and the activity of setting ourselves moral ends, such an analysis enables us to distinguish the weak from the impure and the vicious. 9 Fourth, it does not compel us to abandon the incorporation thesis in order to save the phenomenon of weakness of will.
Finally, it does not commit us to the view that the morally weak agent simply changes his mind.

| PARADIGMATIC SOLUTIONS
In this section, I consider a cluster of solutions to the puzzle of how to understand Kant's notion of moral weakness through the prism of its two aspects, namely, weakness as expressed at the level of following maxims and weakness as expressed at the level of adopting them.
The available secondary literature appears to accept the widespread, often tacit assumption that Kantian moral weakness is only exhibited at the level of observing maxims. To my knowledge, only Stephen Engstrom (1988, p. 441) makes this assumption fully explicit by arguing that it is clear that "the frail agent's weakness is not expressed in any maxim." "If the weakness were expressed in a maxim, " Engstrom (1988, p. 441) continues, "then we could not say that the agent does not will the conduct manifesting the frailty." 10 Engstrom (1988, p. 441) consistently concludes that frailty is not a genuine evil and that even someone who was attempting to carry out evil principles might be hampered by weakness.
For different reasons, Richard McCarty (1993) also maintains that weakness is merely expressed at the level of following maxims. On his view, Kant's treatment of weakness enables us to accommodate those cases in which we have a good maxim but still fail to live up to it. Accordingly, McCarty discusses Kant's account of weakness as a counterexample to the view that it is not possible for someone to regard the moral law as an all-sufficient reason for action and to lack the motivation to act morally. 11 The maxims of the weak agent are genuinely moral; he simply lacks the moral strength to compel himself to follow them. For McCarty (1993, p. 429), the strength of moral feeling seems to be crucial in this regard-if it is sufficiently strong, then we perform particular acts in accordance with our maxims.
The impure "have sufficient strength" but do not recognize the moral law as providing an all-sufficient reason for action; those who are "pure in heart but frail" recognize the authority of the moral law in that sense but occasionally fail to act morally due to weakness (McCarty, 1993, pp. 426, 431). 12 In his later interpretation of moral weakness, McCarty (2009, p. 37) assigns a more prominent role to maxims: His contention is that moral weakness is about "the action-explaining forces of the incorporated incentives." On his view, the explanatory force of a maxim lies in its psychological aspect; by going back to "the two-world interpretation," McCarty argues that maxims are explained by the incentives that give them psychological force. In the case of moral weakness, the psychological force of the subjective dimension of the moral incentive is insufficient, and this is why the moral action prescribed by the maxim is omitted. Although McCarty here explicitly links the strength of the moral incentive with maxims, he seems to do so by merely pointing to that aspect of a maxim that belongs to the psychologically deterministic world.
Robert Johnson (1998) provides a more nuanced account. He first characterizes weakness as a kind of failure to live up to a principle by referring to Kant's suggestion that virtue at the phenomenal level corresponds to the legality of one's actions (R 6: 47). For Johnson (1998, p. 359), at the heart of moral weakness is a Gesinnung with properly ordered incentives, which is "quite compatible with a lack of (empirical) virtue." Johnson's point, like McCarty's, therefore seems to be that the Kantian weak-willed agent simply lacks strength in compelling himself to adhere to his maxims. An examination of Johnson's rich account, however, reveals that he can consistently allow only for weakness in following one's fundamental or underlying maxim.
To capture the conflict characteristic of weakness of will, Johnson emphasizes the difference between specific maxims and a person's fundamental maxim. His point is that the weak-willed person's disposition is morally good, whereas his particular maxims are morally incorrect. Johnson (1998, p. 362) claims that "the weak and the vicious both incorporate wayward incentives into their motives"-they are both motivated by the same kinds of particular maxims, and the difference lies "in how they incorporate incentives into their values." Both seem to have and to follow morally incorrect maxims, but the weak agent acts against his own deepest commitments, because he does not have an evil disposition. As Johnson (1998, pp. 361-362) illustrates this point, when making a snide comment to a colleague, the weak and the vicious are both "motivated by a maxim of doing so"-the only difference is that such a particular maxim conflicts with the weak person's "deepest values," whereas the vicious person does not really condemn it "deep down." The weak agent's underlying maxim is good because he properly incorporates incentives into his values, but his particular maxims are morally incorrect because he incorporates "wayward incentives" into his motives: His justifying reasons do not really motivate him. That is, the adopted principles on which he ought to act, or his deepest commitments, are not the principles that actually bring him to act.
Mark Timmons (1994) also applies the conceptual distinction between motivating and justifying reasons. However, he argues that the morally weak person must have an evil disposition, and he allows for moral weakness at the levels of adopting and observing (particular) maxims. He claims that the essential difference between "morally weak behaviour and morally impure behaviour is one of moral luck": Unlike the weak, the impure does perform the act that he judges he has most reason to perform just because his nonmoral reasons happen to move him (Timmons, 1994, p. 129). Timmons's explanation of the difference between the weak and the impure at the level of maxim adoption also seems to rely heavily on the idea of moral luck.
As will become apparent, my reading comes close to Timmons's account. I believe that the fact that Kant addresses weakness as the first stage of our propensity to evil lends support to the claim that the morally weak agent's disposition is evil. Additionally, together with Kant's claim that evil must be sought in one's "perverted maxims" (R 6: 57n), this fact suggests that weakness exhibited at the level of maxim observation does not exhaust the scope of Kant's conception of moral weakness.
Finally, when combined with the distinction between motivating and justifying reasons, the point that the weakwilled agent's disposition is morally good does not appear to leave room for the impure agent. Even if Johnson's approach makes it possible for us to distinguish between the vicious and the weak in terms of their different underlying maxims, we do so at the cost of being unable to explain what makes the impure agent distinctive. To the extent that the impure agent has a morally good disposition, her failure is conflated with weakness; to the extent that her disposition is evil, it is conflated with vice.
With that said, Timmons's explanation of the difference between moral weakness and impurity does not seem to be completely satisfying either. In my view, acting in accordance with our maxims does not have to be a matter of luck; it can be spelled out in terms of strength of self-control (or lack thereof) at the level of observing maxims.
The difference between the maxims of the weak and the impure can also be better explained by appealing to the different ways in which they exercise their capacity for self-control at the level of maxim adoption-the ways in which they allow nonmoral incentives to exert a stronger motivational pull. In what follows, I therefore analyze moral weakness as a mere lack of moral strength or as a mere failure to properly exercise our capacity for self-control. First, the frailty (fragilitas) of human nature is expressed even in the complaint of an Apostle: "I have the will, but the execution is lacking [Wollen habe ich wohl, aber das Vollbringen fehlt]" i.e. I incorporate the good (the law) into the maxim of my power of choice; but this good which is an irresistible incentive objectively or ideally (in thesi), is subjectively (in hypothesi) the weaker (in comparison with inclination) whenever the maxim is to be followed. (R 6: 29; translation modified) Even though Kant often seems to use the terms "weakness of heart" and "frailty" interchangeably, he also makes a subtle distinction between them. The good heart is a capacity [Fähigkeit], pertaining to choice [Willkür], to incorporate [aufnehmen] the moral law into its maxims, whereas the evil heart is an incapacity [Unfähigkeit] with regard to doing the same (R 6: 29). Frailty is the first stage of a natural propensity [Hang] to evil, which "must reside in the subjective ground of the possibility of the deviation of the maxims from the moral law" (R 6: 29). Kant's suggestion is that the quality of a person's heart originates in or arises from this propensity (R 6: 29). 13 Just as, more generally, a propensity is "the subjective ground of the possibility of an inclination" (R 6: 29) that arouses an inclination to a certain object when one becomes familiar with it, so too the propensity to evil may result in an evil heart, which incorporates deviation from the moral law by allowing the incentives arising from the objects of inclination to determine one's choice. 14 Instead of trying to explain the origin of the first grade of our propensity to evil, in what follows, I shall instead try to describe how the frailty of human nature manifests itself in ever-new situations as the weakness of the human heart.
Kant's notion of the human heart as a necessary capacity when it comes to the proper incorporation of the moral law into maxims is inextricably linked to his notions of incentive, moral worth, and disposition (e.g., R 6: 48). For example, Kant has been reported as saying that the "[h]eart is the principium of moral disposition" (LE 27: 274). Moreover, his understanding of the good human heart seems to come very close to his definition of virtue as "the firmly grounded disposition [die fest gegründete Gesinnung]" to act from duty (R 6: 23n; 6: 14). If so, an agent who fails to acquire a virtuous disposition or who does not strive to attain the ideal of moral perfection in new situations can probably also be said to lack a good heart.

| Moral weakness at the level of maxim following
The passage cited above makes clear that moral weakness must involve a failure to adhere to one's maxims-that the appropriate deed, in the sense of an action through which one follows one's maxims, is missing. Certainly, weakness entails lack of moral strength in compelling oneself to perform morally good actions-an absence of the strength required to bridge "a wide gap" between maxim and deed (R 6: 47). For this reason, moral weakness can be partly understood as a lack of phenomenal virtue or lack of "a skill [Fertigkeit] in actions [Handlungen] conforming to duty (according to their legality)" (R 6: 14; translation modified). The weak agent, then, lacks the skill to compel himself to act a certain way: He has problems disciplining his inclination with a view to following certain rules (R 6: 57n).
One of the reasons why the weak agent fails to follow his maxims may be that he has not done much to increase his own natural perfection-to cultivate his capacities in order to use them as means to realize all kind of ends, that is, for a pragmatic purpose. For instance, it is through exercising our capacity for judging in different situations that we become more skillful in fulfilling the duties of virtue. Generally, further development of our capacities facilitates acting in accordance with our maxims.
The weak might also be under the sway of an affect, and the relation between weakness and affects has been extensively discussed. To explain weakness, commentators often refer to Kant's claim, regarding affects, that "weakness in the use of one's understanding coupled with the strength of one's emotions [der Stärke der Gemüthsbewegung]" is "only a lack of virtue [Untugend] and, as it were, something childish and weak, which can indeed coexist with the best will [mit dem besten Willen]" (MM 6: 408). Johnson (1998, p. 359), for example, uses this claim to justify his point that the morally good disposition of the weak is compatible with a lack of "empirical" virtue, while some other scholars read "the best will" mentioned in the quotation quite differently. Frierson (2014, pp. 237-238), for instance, seems to hold that this term actually makes this quotation unsuitable as a means of describing Kantian moral weakness; he warns that Kant's account of affects should not be used for the purposes of explaining weakness because Kant emphasizes that affects are not evil. On Frierson's (2014, p. 215) interpretation, affects represent a separate volitional defect.
But the fact that Kant there mentions "the best will" in relation to affects may suggest that the quotation is neither so relevant nor so unsuitable when it comes to specifying his concept of moral weakness. In the Religion, Kant suggests that the good will is present even in a "corrupted [verderbten] heart" (R 6: 44), or the heart corresponding to the third stage of our propensity to evil (R 6: 30). 15 This tells us that the good will and the corrupted heart can go hand in hand. Hence, if Kant has in mind the same good will in the discussed quotation from the Metaphysics of Morals, then the lack of virtue that can coexist with the best will does not specify the first stage of evil exclusively.
In fact, however, I agree to a certain extent with both positions: Weakness can be understood as lack of virtue, and Kant's point about affects not being evil may make us wonder whether the lack of self-control that they cause matches up with the type of weakness that Kant discusses in the Religion. But the Kantian weak heart, as the manifestation of the first grade of our propensity to evil, cannot be completely described as a lack of phenomenal virtuethat is, as a mere failure to perform legally good actions. And even though Kant's treatment of affects cannot fully cover his conception of weakness, it can still be regarded as one of its elements.
While we are in brief states of affect, we can be said to lack virtue as moral strength: When all our powers are "paralyzed" and we lack self-control, our hearts may be too weak to comply with our maxims. Being in such a state might indeed explain why an agent lacks phenomenal virtue-that is, why he fails to acquire the skill of compelling himself to adhere to his maxims by performing legally good actions (R 6: 47). To make sure that we perform such actions, we must therefore prevent ourselves from entering into affective states. We can do this by cultivating our feelings or by disregarding certain sensible influences on our minds, so that we do not allow our feelings to turn into affects. In this way, we can ensure that we will act in accordance with our maxims, and our hearts may be called weak with regard to complying with our maxims when we fail to do so.
But this account does not yet tell us why the morally weak fails to perform a morally worthy action-it only tells us why he fails to perform a legally good action. One may object that the judgment about whether an agent has performed a legally good action does not suffice to characterize him as morally good or evil because we still do not know whether the maxim he has followed or has failed to follow was genuinely moral. So even if we conclude that an agent does not lack phenomenal virtue, we are still left with the question of whether he has properly incorporated the moral law into his maxims.
Further analysis of Kant's account of affects shows that the lack of virtue exhibited in brief affective episodes does not have to be understood as a bare failure to perform actions on the basis of established maxims. Affects can also be seen as obstacles to the adoption of moral maxims. Kant points out that being free of affects is the necessary condition for acquiring inner freedom (MM 6: 407), which is required if we are to adopt moral maxims. He relatedly argues that we have a duty of apathy, which requires that we should be free of affects because they make it impossible (or very difficult) for us to freely consider principles and to determine our choices in accordance with them (C3 5: 272). Affects hinder self-determination, and this seems to be the main reason behind Kant's assertion that virtue necessarily presupposes apathy as strength (MM 6: 408). Ensuring that we are free of affects by using our capacity to disregard the sensible impressions that may arouse affects might therefore also be understood as a necessary step in the adoption of moral maxims.
In addition, this analysis supports the claim that being in an affective state, at least indirectly, can be understood as an aspect of Kant's conception of moral weakness, conceived as a lack of the moral strength in which virtue consists. And yet, if understood simply as lack of moral strength due to affects, lack of virtue still does not suffice as a specification of the nature of Kantian moral weakness. Kant is emphasizing that the ground of evil must lie in a maxim (R 6: 20-1; 6: 31), and the adoption of a moral maxim requires that we take a step further, that is, that we set aside all other feelings on which inclinations are based. Furthermore, Kant's notion of lack of virtue [Untugend] as a deviation from weakness or a lack of firmness with regard to one's principles [Abweichung aus Schwäche (mangel an Festigkeit der Grundsätze)] (NMM 23: 396) certainly covers more than lack of self-control when it comes to affective states.
Finally, if it is true that moral strength is necessary for the adoption of moral maxims, we can claim that weakness, as "lack of moral strength (defectus moralis)" (MM 6: 390), is also expressed at the level of maxim adoption.
Kant's distinction between weakness as "mere lack of virtue [blos Untugend]" and vice [Laster] (MM 6: 390; 6: 384), then, does not commit us to the claim that moral weakness can only be expressed at the level of following our maxims.

| Moral weakness at the level of maxim adoption
Without a further description of mere lack of virtue as lack of moral strength, we miss out on an important tool for distinguishing between the maxims of the weak willed and those of the impure and the vicious. In my opinion, the core of the problem of how moral weakness is to be understood on Kant's framework is then in fact sidestepped. Some commentators are likely to disagree with this claim, at least in part. As mentioned above, Johnson holds that the weak agent may have the same particular maxim as the vicious, such that only their underlying maxims differ.
In a similar vein, Thomas Hill (2012, p. 146) argues that the morally weak agent "must be viewed as having two conflicting maxims: a basic maxim to conform to morality's unconditional requirements and a shorter-term maxim reflecting an intention to indulge self-love on the particular occasion." This way of accounting for the inner conflict of the morally weak seems to rest on a very sharp distinction between particular and underlying maxims. The latter are thought to be completely static, for they are meant to represent our deepest commitments, which are made once and for all, independently of our particular maxims. Additionally, this kind of solution works only on the assumption that the morally weak agent's underlying maxim or disposition is morally good. As I explained in the remainder of this section, however, we need not presuppose either that two completely separate maxims are in question or that the weak agent's disposition, or the subjective ground of his maxims, is a genuinely good one. In addition, we need not understand this subjective ground as something that is determined once and for all.
Furthermore, if we were to argue that there is no difference between the particular maxims of the weak and the vicious, we would have to interpret weakness as an "intentional [vorsetzliche]" transgression that "has become a principle [Grundsatz]," which is how Kant actually explains vice (MM 6: 390). In other words, we would not be talking about moral weakness anymore or about a mere lack of virtue, which Kant describes as "0" (MM 6: 384; R 6: 22n).
Instead, we would be conflating this "negative lack of virtue" (MM 6: 384) with a lack of virtue that is also positive.
On Kant's view, we can speak about intentional guilt [vorsätzliche Schuld] only when it comes to the vicious (R 6: 38), who represents the third grade of our propensity to evil. The vicious person's intentional transgressions of the moral law are based on his maxims, in which he consciously reverses the ethical order of the incentives. Kant's portrayal of the "moral egoist" offers an apt illustration of the vicious. A moral egoist "puts the supreme determining ground of his will simply in utility and happiness, not in the thought of duty" (A 7: 130). This implies not that Kant's moral egoist is not aware of the moral law but that he fails to adopt maxims in which the law is properly incorporated because of his egoism. He adopts maxims to act in accordance with his empirical ends. When adopting his maxims, the moral egoist starts from the ends that he is anyway eager to adopt, does not constrain himself to adopt moral ends, and therefore adopts his maxims on empirical grounds.
Unlike the moral egoist, the morally weak agent does not yet seem to locate the determining ground of his will in one of his self-seeking interests. The maxims of the morally weak do not seem to be based on particular ends that are determined by his inclinations, or he does not seem to adopt maxims on empirical grounds by intentionally reversing the ethical order of the incentives. Claiming that the weak agent adopts and follows such maxims would make it very hard to understand why he is merely morally weak and not also vicious. This is why I also disagree with attributing a kind of passionate maxim to the Kantian morally weak person. 16 On my interpretation, Kant's account of the passions can only be used to portray the vicious. Having passions indicates a lack of moral strength (of self-control), which, from a moral perspective, is a more severe deficit than that exhibited by the frail person, for it can also be seen as a misuse of one's capacity for self-control. Passions presuppose a maxim in which evil is taken up as something intentional [vorsätzlich] (MM 6: 408). The person under the influence of the passions seems to believe that making an exception for himself is justifiable, and this distorts his way of thinking at its very root. This is also how Kant describes the vicious agent: He reverses the ethical order of incentives and thereby corrupts his way of thinking [Denkungsart] at its root (R 6: 30). His maxims cannot be said to involve a general intention to do what duty commands.
Unlike the vicious, the weak and the impure can be said to have a general intention to do what the moral law demands. At a very general level, the weak seem to intend to act morally-they want to do what they ought to do (R 6: 29). And as Kant explains with regard to impurity: "The maxim is good with respect to its object (the intended compliance with the law)" (R 6: 30). The difference lies in their reasons for intending to comply with the moral law.
Whereas the weak wish to comply with the moral law for morally acceptable reasons, the impure intend to comply with the law from morally unacceptable motives. This seems to be why Kant suggests that the maxims of the impure are "not purely moral" (R 6: 30) and why he does not describe the maxims of the weak this way. I therefore agree with Johnson and Hill that the morally weak agent has a kind of general, pure commitment to do what is right. On my interpretation, he sets himself moral ends in an abstract or merely intellectual way. The objective determining ground of his choice, or a formal aspect of an end that Kant calls an intention or purpose [Absicht (intentio animi)] (NMM 23: 389), might be characterized as good. 17 This is how I understand Kant's suggestion that the weak agent incorporates the moral law as the good that is "an irresistible incentive objectively" (R 6: 29). A necessary step in the process of adopting moral maxims therefore seems to have been completed.
As I shall elaborate, however, I do not think that this explanation suffices to show that the disposition of the morally weak agent is genuinely good, because his abstractly good commitment to the moral law remains fragile in practice. And since there is no middle position between good and evil for Kant (e.g., R 6: 24; 6: 22n), we must still conclude that the weak agent's disposition is evil.
Let us now return to the discussion of the relation between the maxims of the weak and those of the impure.
Revealingly, Kant mentions a further difference: Unlike the impure, whose maxims can be "powerful enough in practice" (R 6: 30) in that they result in legally good actions, the maxims of the weak are not effective in practice.
These maxims do not result in actions, although, unlike the maxims of the impure, they seem to have the potential even to result in morally worthy actions.
The maxims of the weak do not lead to the realization of ends, and the question is why. I think that a full answer to this question must reach beyond an explanation of why the weak agent fails to follow his maxims and must in addition address his weak maxims-that is, the maxims that are impotent in practice. 18 Thus, a proper solution to the puzzle of Kantian moral weakness requires that we determine when a maxim with an internal or pure motivating ground fails to be motivating in practice. It forces us to try to answer the difficult question of how one can incorporate the law as an objectively irresistible incentive but still fail to be sufficiently morally motivated to perform the corresponding action because that incentive is subjectively weaker in practice.
If the criterion for distinguishing moral good from evil is simply whether one has incorporated the law, then the weak heart cannot be morally evil, for Kant argues that the weak agent in a certain sense incorporates the law. 19 And indeed, he sometimes leads us to think that this is his criterion (R 6: 29; 6: 44). But Kant also offers a more sophisticated version of this criterion, on the basis of which we might resist the conclusion that moral weakness is morally good, namely, he also argues that we incorporate both the incentive of the moral law and the incentives of inclination, so that the difference between good and evil must lie in the way these incentives are incorporated: One must be made the condition of the other (R 6: 36). The way in which we incorporate the moral law into our maxims is crucial: The law must be incorporated, not as merely bound to other incentives or subordinate to them "but rather in its full purity, as the self-sufficient incentive [für sich zureichende Triebfeder]" of the determination of our power of choice (R 6: 46). Kant's suggestion is that being morally good means that one has incorporated the law into one's supreme maxim [oberste Maxime] as a by-itself-sufficient [für sich allein hinreichend] determination of one's choice (R 6: 36).
Like all other agents, the weak-hearted agent also incorporates the incentive of the moral law, but he nonetheless fails to incorporate the law as the self-sufficient incentive in his supreme or underlying maxim, and his heart can therefore be characterized as morally evil.
First, I would like to mention some of the benefits of this more sophisticated version of the criterion. For one, it squares well with other important points made by Kant. It is in line, for example, with Kant's claim that we can never be morally indifferent in the sense of completely lacking the incentive of the moral law (e.g., R 6: 24 and 6: 22n).
Furthermore, as will be clarified, it enables us to reconcile the incorporation thesis with weakness of the will, as commonly conceived. The seeds of this reconciliation can thus be found within Kant's own theory, such that, for example, we need not modify the incorporation thesis by employing the conceptual distinction between values and motives-as Johnson does, for instance.
The application of this criterion suggests that both the weak and the impure fail to make the moral law a selfsufficient incentive that determines their choices. The incentive of the moral law motivates the weak and the impure to perform their actions only when assisted by other incentives. Their choices are therefore determined by sensible impulses. They are not properly characterized as morally good, for their powers of choice are not in agreement with the law (R 6: 22n). The weak and the impure can therefore be said to incorporate deviation from the law into their choices (R 6: 24).
And yet, if my interpretation is correct, the maxims of the weak and the impure are still distinguishable in terms of their quality. Whereas the maxims of the impure might be called strong because they can be powerful in practice and result in actions, the maxims of the weak are not powerful in practice. Moreover, the former are not morally strong because they are not "purely moral" (R 6: 30), and strictly speaking, the latter are not yet morally strong and also not yet impure.
Although the weak and the impure can both be said to incorporate the incentive of the moral law improperly, they seem to do so for different reasons and in slightly different ways. To become sufficiently morally motivated in particular situations, the weak, like the impure, seem to be in need of incentives other than the representation of duty itself. Yet they do not thereby adopt impure maxims based on the incentives of inclination. In a certain sense, the subjective motivating ground of the maxims of the weak agent is pure-in abstracto, he intends to comply with the moral law for morally acceptable reasons, but this intention is ultimately fragile in practice because he seems to postpone the adoption of particular moral maxims that are efficient in practice. The weak agent therefore also gives priority to sensible incentives in his maxims, but he does so by merely failing to renew his commitment to the moral law by reassessing his incentives in new situations. The impure agent seems to take a step further to the extent that he adopts impure maxims in which the priority is more explicitly given to morally unacceptable incentives to follow the moral law. Even though the basic formulations of their maxims may be the same, their subjective motivating grounds are different.
A passage from the Metaphysics of Morals can help us to clarify what precisely goes wrong at the level of maxim adoption in the case of the morally weak. In short, Kant argues in this passage that all lawgiving consists of two elements: a law, which represents an action as objectively necessary (makes it a duty), and an incentive, which is required if we are to connect a ground for determining choice to perform this action with the representation of the law subjectively (MM 6: 218). Whereas the first element suffices for "a merely theoretical cognition of a possible determination of choice," the second is required for actual self-determination (MM 6: 218).
Accordingly, Kant's point seems to be that there is only something wrong with the subjective ground of the maxims of the morally weak, that is, with the motivating ground that enables actual self-determination. The purely cognitive or theoretical basis of their maxims seems to be good. The maxims of the weak agent seem to lack a proper element that would make them, as Kant puts it, "subjectively practical" (LM 28: 317) or "subjectively possible" (LM 29: 900). 20 Objectively, as regards the rule, his maxims are good; but subjectively, as regards the incentive, they are not (R 6: 58n). For the weak agent, the moral law is not also a powerful incentive to action. For him, the incentive of the moral law is irresistible ideally, or "in thesi," but the subjective ground or foundation of its irresistibility is weak-"in hypothesi," this incentive is weaker than his inclinations (R 6: 29). The maxims of the morally weak therefore lack adequate motivational strength: The pure subjective ground that should motivate the weak agent to act morally is not powerful enough to win over his inclinations.
On this account, the morally weak agent takes a necessary step in adopting moral maxims but fails to take another equally necessary step. He can therefore be said to adopt moral maxims in a certain sense: On a purely theoretical and intellectual level, he seems to determine his choice. However, his particular maxims look more like practical laws-they do not "also serve" him "subjectively" as practical principles (G 4: 401n). 21 Hence, his particular maxims are actually not what they should be, that is, they are not subjective practical principles of volition. For this reason, they are weak. This is how I suggest that we read Kant's suggestion that the weak agent is not "strong enough to comply with" his "adopted principles [genommenen Grundsätze]" (R 6: 37).
Elsewhere (Vujošević, 2017), I argue that it is through the constant exercise of our capacity for moral self-control or through the acquisition of moral strength that our maxims become the principles that actually guide and motivate our actions in practice; it is only via a constant effort to disregard the influence of sensible impressions on our mind that we can set ourselves moral ends in ever-new situations. Moreover, I interpret the intention the strength of which Kant calls virtue (MM 6: 390) as an intention by which we set ourselves particular moral ends, and I claim that our maxims of virtue must include this intention if we are truly to be motivated by the pure moral incentive to perform an action. Without such an intention, our maxims cannot be subjectively practical principles of our own volition.
On the basis of these and previous considerations, I now conclude that the morally weak agent lacks virtue, understood as the acquired strength of moral self-control. He lacks the strength of intention needed to set himself moral ends in ever-new situations. For this reason, the weak agent's maxims do not seem to be subjectively practical and instead look rather like objective principles, which would have been his own practical principles if he had complete control over his sensible desires. In order for his maxims to become what they should be-subjective and practical principles of volition-the weak agent would have to continuously exercise his power of self-control and thereby set aside various sensible influences. This, however, is precisely what he fails to do.
Furthermore, the weak agent remains insufficiently motivated to act morally because he takes no interest in the particular instantiations of moral ends while adopting his weak maxims. Kant relatedly suggests that a maxim is genuinely moral only if it is based on this pure interest in compliance with the moral law and that frequent exercise of the power of self-control gradually produces this pure moral interest in us (C2 5: 79; 5: 159). Establishing this kind of interest in the action, which is implicit in every genuinely moral maxim, requires that we make use of our capacity for self-control or abstraction: By diverting our attention from all sensible impressions, we attend to a kind of interest that differs from the interest of the inclinations. The morally weak agent does attend to this pure interest in moral ends because he does not frequently exercise his power of self-control, with the result that the incentive of the moral law cannot gain sufficient motivational force to move him to act morally. The incentive of the moral law still "does not have a driving force so strong as the sensory one" (LE 27: 293) and therefore does not determine his choice independently of sensible impressions.
This means that there is something wrong with the subjective motivating ground or the deep ground of the maxims of the morally weak person. On my view, his disposition, understood as the "subjective principle" or "inner principle" of his maxims, cannot be morally good (R 6: 37; 22n): His underlying maxim remains impotent in practice because he does not acquire moral strength in ever-new situations.
In the Metaphysics of Morals, Kant treats moral feeling as the subjective ground on which we morally determine our choices. All of us have moral feeling, for it is one of the natural predispositions of the mind [Gemüthsanlagen] to being affected by the concepts of duty (MM 6: 399). We ought to cultivate this predisposition, however, if we are to become sufficiently motivated to perform morally worthy actions. Without its cultivation, we cannot enter into an actual state of self-determination.
On the basis of Kant's linking of moral feeling, determination of choice and the activity of taking an interest in the action (MM 6: 399), we may further conclude that the morally weak agent does not enter into a state in which he takes an interest in the action because he fails to cultivate his susceptibility to moral feeling. 22 Since effective moral motivation, or taking an interest in the action, is possible only insofar as we cultivate moral feeling, the morally weak agent fails to enter into a state in which the moral law actually determines his power of choice with respect to an action relating to it. 23 That is, his maxims remain weak, or impotent in practice.
Kant also suggests that it is via the cultivation of moral feeling that we intend every particular end that is also a duty (MM 6: 387). So the morally weak agent does not intend a particular moral end (or takes no interest in a particular moral end) because he does not cultivate moral feeling.
Crucially, Kant implies that moral feeling is the purest virtuous disposition [Tugendgesinnung], which is the end of moral perfection (MM 6: 387). Furthermore, he suggests that we attain this virtuous disposition by cultivating the will or our "moral way of thinking [sittlicher Denkungsart]" (MM 6: 387). His contention seems to be that we cultivate moral feeling or achieve a virtuous disposition by adopting particular moral maxims. The weak agent, then, does not seem to cultivate moral feeling to attain the purest virtuous disposition, for he does not actually cultivate his will or his moral way of thinking through adopting moral maxims in ever-new situations. He might be said to set himself the end of moral perfection, but only in the sense of having an overly general, wishful intention to cultivate his will to the level of the purest virtuous disposition. The intention is wishful because his weak (or deficient) maxims remain fragile in practice. Even though the weak agent might be said to set himself moral perfection as an end in abstracto, in concreto he fails to acquire moral strength by exercising his capacity for self-control (or to set aside all sensible impressions). He therefore fails to adopt maxims in which the moral law is incorporated as a self-sufficient incentive.
This reading is in perfect agreement with Kant's discussion of the relationship between moral feeling and our way of thinking [Denkungsart] in the Religion. Kant here argues that moral feeling is not a mere susceptibility to respect for the moral law but rather the subjective ground on which we incorporate the law into our maxims as a self-sufficient incentive; he states that the idea of moral law and respect can be called a predisposition to personality because it also involves this subjective ground (R 6: 27-8). 24 Moral feeling is therefore our original predisposition [Anlage] to the good (R 6: 27-8), and Kant's point is that this predisposition gradually becomes a way of thinking by which the moral law becomes a self-sufficient incentive. As Kant emphasizes: from our own perspective, the reformation of our propensity to evil as a perverted way of thinking [verkehrter Denkungsart] is always gradual because we can judge ourselves and the strength of our maxims only on the basis of the control over the input of sensibility that we gain in time (R 6: 48). 25 The agent who does not acquire moral strength by properly exercising his capacity for self-control in ever-new situations can be said to have a weak heart and weak maxims-he can be said merely to lack virtue, understood as the firmly grounded disposition to act from duty (R 6: 23n; 6: 14). The proper exercise of our capacity for moral self-control, which is essential to virtue as acquired moral strength, enables us to overcome incentives to transgress via a continuous effort to sustain the firmness of our general moral intention in the face of contrary inclinations. It is only through such firmness of intention that we can struggle with the temptation to give priority to the incentives of inclinations in our maxims. The morally weak agent does not exercise this capacity in ever-new situations, and thus, the subjective determining ground of his choice remains impotent in practice. Since he does not cultivate moral feeling by adopting particular moral maxims, he does not become "affected" by his theoretical cognition of what he ought to do.
He does not actually restore the essential aspect of his original predisposition to the good, because he fails to gradually acquire virtue, understood as a constant disposition to act from duty.
The weak agent is not strong enough to comply with the principles that he endorses on an abstract level because he seems to postpone making these principles "subjectively practical." Even though, for morally right reasons, he generally wills to do what the moral law commands and sets himself moral ends in a purely theoretical way, in practice, he fails to make his will strong by putting aside all inclinations and the feelings on which inclinations are based. For example, although he generally holds that he should help those in need and makes the happiness of others his end in abstracto (i.e., although he has a general intention to help for morally acceptable reasons), this does not sufficiently motivate him actually to help others. The rule "help others in need" does not become a subjectively practical principle that moves him to perform the relevant actions. He fails to secure the purity and strength of his moral incentive in ever-new situations by "bracketing" the influence of his inclinations. That is, he fails to renew his general commitment to the moral law over time by adopting particular moral maxims on which he really does act.
Once he succumbs to the temptation to adopt impure maxims, he becomes not only weak but also impure. To use the same example, he adopts the maxims that often result in acts of helping others, but he does not do so "from duty," that is, his particular maxims have impure motivating grounds. This is why Kant speaks about stages [Stufen] of evil and treats frailty as a first step that leads to impurity and remains present in it. As he explains, when frailty is coupled with "dishonesty in not screening incentives (even those of well-intentioned actions) in accordance with the moral guide," one may come to see "only the conformity of these incentives to the law" (R 6: 37). If there is also dishonesty when it comes to approving or disapproving incentives, the weak-willed agent easily becomes impure as well: He adopts impure maxims which result, at best, in legally good actions.
But even if the weak heart does not become impure and/or vicious, the way of thinking characteristic of the morally weak cannot rightly be characterized as virtuous, for even if, in a certain way, he adopts the principle of giving priority to the incentive of the moral law, he actually fails to do so in practice, taking mere wishes, which "always remain empty of deeds, for proof of a good heart" (MM 6: 411). 26 This is why Kant treats the weak heart as a manifestation of one of the "three sources of evil" (R 6: 32). The morally weak agent does not adopt morally correct particular maxims that are efficient in practice. Although he has a general intention to follow the moral law "from duty," his overly general intention to act morally remains impotent in practice. He fails to make certain objects his ends in accordance with the concepts of duty which, on a purely intellectual and abstract level, he seems to possess. In ever-new situations, he does not exercise his capacity for moral self-control and thereby set aside all sensible impressions, and he therefore actually fails to set himself particular ends that are at the same time duties.
The inner conflict experienced by the morally weak agent is not a conflict between his morally incorrect particular maxims and his good underlying or supreme maxim. Nor does he adopt the same particular maxims that the vicious agent does or cultivate a morally good disposition. Instead, the following description seems to capture his inner conflict best: in abstracto, the weak-willed agent has the will to do what the moral law requires; in concreto, however, he does not make an effort to strengthen his general moral intention by setting himself moral ends in ever-new situations.

| CONCLUSION
Kant's conception of moral weakness should not be simply understood as a failure to act in accordance with our genuinely moral maxims, for such a reading cannot fully capture Kant's point that moral weakness represents the first grade of moral evil. By indicating how moral weakness, as a mere lack of moral strength, is expressed both at the level of adopting maxims and at the level of following them, the analysis offered here unifies both aspects put forward by Kant.
On my interpretation, the Kantian morally weak agent is also, and even primarily, someone who lacks moral strength in constraining himself to adopt moral maxims that are powerful in practice. He wills the good but not strongly enough to move him to perform a morally right action. That is, what the morally weak agent lacks is a settled intention to determine his choice by diverting attention away from his inclinations and instead focusing it on a particular moral end. He can therefore be described not only as lacking an intention to perform an action in order to follow a maxim but also as lacking the intention that is essentially involved in adopting moral maxims of virtue.
My point is neither that the weak agent adopts and follows the same morally incorrect maxims as the impure and the vicious nor that he simply changes his mind by dropping his adopted principle. Rather, he postpones the adoption of moral maxims of virtue in ever-new situations; his maxims do not become subjectively practical because he fails to acquire moral strength.
This account does not compel us to abandon the incorporation thesis in order to save the phenomenon of weakness of will, and it can tell us why moral weakness counts as moral evil. The morally weak agent is not simply overpowered by his habitual sensible desires; in a certain way, he takes an active stance regarding his inclinations.
However, he still fails to incorporate the moral law as a self-sufficient incentive. He fails to enter into a state of actual self-determination because his moral intention is not firm in the sense of continually engaging in the purifying (or self-controlling) activity that the adoption of specific moral maxims of virtue, as our subjectively practical principles of volition, requires. For this reason, his commitment to the moral law is not fully genuine. The Kantian weak-willed agent fails to carry out his overly general commitment to the moral law in practice. 27 ENDNOTES 1 References are to Kants gesammelte Schriften. Ausgabe der Preussischen (later Deutschen) Akademie der Wissenschaften (Berlin: Georg Reimer, subsequently Walter de Gruyter, 1900-). Except where indicated otherwise, translations are based on the Cambridge Edition of the Works of Immanuel Kant, eds. Paul Guyer and Allen Wood (Cambridge: Cambridge University Press, 1992-). References to Kant's works are given using the following abbreviation scheme:  (2009) pays close attention to it. It seems to me, however, that his account of the link between moral weakness and the moral incentive can be undermined by Kant's caveat that weakness as "the impotence of the incentive of reason," together with the power of incentives of sensibility, cannot simply be explained in terms of natural causes (R 6: 59n). 23 On my interpretation, moral feeling can be considered a point of intersection between the two aspects of moral strength: It comes into play not only once we have adopted a maxim but also in the very process of adopting moral maxims. 24 In the Metaphysics of Morals (6: 464), Kant suggests that moral feeling is the subjective aspect of respect for the moral law. 25 For this reason, I do not think that Kant's points about a radical change of heart must be taken as evidence against the idea that there is a sufficient degree of commensurability between his accounts of virtue in the Metaphysics of Morals and in the Religion. Besides, it seems that, because of the limits to self-knowledge, we cannot even know for sure whether such a radical change has occurred. 26 As far as I can see, it is only this quotation that can be taken to imply that self-deception plays a role in Kant's account of moral weakness, because it may suggest that the weak person deceives himself into thinking that his mere wishes are proof of his moral goodness. My reading does not preclude the possibility of the morally weak agent's sometimes also deceiving himself into thinking that he cannot compel himself to act morally in some situations. However, it does not have to lean on Kant's notion of self-deception to pinpoint what is wrong with the weak agent's commitment to the moral law or to claim that he is by definition not aware of what he ought to do. I think that this suffices to avoid the main objection to Allison's reading, namely, that by explaining weakness in terms of self-deception he actually denies the phenomenon of weakness of will, where the agent knows what he should do but fails to act accordingly. 27 I am grateful to the Nederlandse Organisatie voor Wetenschappelijk Onderzoek for supporting my work on this article. I would also like to thank the anonymous referee and Pauline Kleingeld for their valuable comments.