The Virtues of Will-Power – from a Philosophical & Psychological Perspective

Virtue ethics is currently one of the most widely known ethical theories. According to it, to act morally well, one needs to perfect one’s moral character by acquiring virtues. Among various virtues, we can distinguish the group of so-called virtues of will power to which, among others, belong self-control, decisiveness, patience, etc. As they are necessary for the effectiveness of human actions, they are also called executive virtues. It is doubtful, however, if they deserve the proper name of virtues because they can be used either in the realization of good goals or evil ones. To serve the realization of what is good, they need to be combined with so-called substantial virtues (e.g., benevolence, honesty, or justice). Virtues of will power are often identified with practical skills, and perfecting will power is identified with exercising such practices as playing an instrument, doing some sports, or taking practice in medicine. In my article, I am trying to compare the view of will power virtues with the results in empirical, psychological studies over self-control and self-regulation. I will show to what extent these two descriptions – philosophical and psychological – are congruent. I will also take a closer look at the observed phenomenon of the depleted will, and whether this observation undermines the conclusions assumptions of virtue ethics.


Introduction
The problem of weak and strong will has attracted philosophical attention since antiquity, even though the will was not yet distinguished from intellect as a separate human faculty. Such a distinction became possible only under the influence of the Judeo-Christian, creationist tradition in which God was presented as the one who created the Universe out of His own will (Dihle 1982;Carr 1999). The problem of the existence of free will as a separate faculty has 2 The Virtue of Will Power from a Philosophical Perspective In philosophy, a strong or weak will is grasped in terms of virtues and vices. Philosophers usually focus on such problems as that of acrasia (incontinence), the vice of the inability to act by one's better rational judgment (Aristotle, 1148a8-10). 2 Acrates is someone who does not control oneself but instead surrenders to emotions and desires. Although often thinking that she should do otherwise, such a person acts against herself (Broadie 1991, 266-269). In contrast to this, a person with the virtues of the will power acts following her judgment; no emotion or desire decisively contrary to her best judgment would influence her action.

Virtue of Will-Power
Contemporary virtue ethicists distinguish a whole group of virtues of will power. Robert C. Roberts points to perseverance, resoluteness, courage, patience, and selfcontrol (1984). Similarly, Jan Steutel identifies persistence, endurance, resoluteness, patience, diligence, and temperance (1999). What all these virtues have in common is that they all condition action achieving the intended goals. Their role is mainly to correct our functioning (Foot 2002;Roberts 1984;Steutel 1999), help us overcome various limitations, whether psychological (e.g., laziness or the lack of self-confidence) or situational (e.g., adversities of life). Such virtues are not merely behavioral but also cognitive (e.g., the ability to fight against one's distraction or to overcome one's overreliance on heuristics), or of affective character (i.e., the ability to control one's unwanted emotions and impulses). The virtues of the will power help the agent not to become discouraged and make it easier to realize one's intended goals relentlessly. For this reason, they are also called executive virtues.
Robert Adams also calls them structural virtues. Their excellence, as he puts it, "is a matter of personal psychic strengthability and willingness to govern one's behavior in accordance with values, commitments, and ends one is for" (Adams 2006, 34). In his opinion, these virtues not so much strengthen the role of the agent, as they structure her moral character. It seems, however, that this function cannot be their distinctive feature, as all virtues have it. 3 Although the will power virtues are generally desirable, and their opposites (e.g., indulgence, incontinence, lack of self-control) undesirable, such virtues are morally neutral in the strict sense. When helping people in need, e.g., working pro publico bono in charity organizations, will power virtues may turn out useful. They may help overcome one's temptations to spend excessive amounts of money on one's pleasures instead of devoting it to the poor. They may help motivate one not to give up to discouragement or disappointment in doing the good. But then, a terrorist may also need patience and self-control. Without these features, his vicious plans might be discovered too early or would get stuck somewhere in the middle of realization. Thus, the virtues of will power, as they can be used both for morally admirable actions as well as those calling for condemnation, cannot in themselves be considered ethical. 2 R. Holton distinguishes weak will from akrasia. He mauntains that the cases of the "weakness of will are best characterized not as cases in which people act against their better judgement, but as cases in which they fail to act their intentions" (Holton 1999, 241). Holton refers to "weak will" as it is understood by people in everyday conversations, not as philosophers define it. And when asked who weak-willed people are, regular people respond: "the irresolute; they do not persist in their intentions; they are too easily defected from the path they have chosen (Holton 1999, 241). In this paper, I understand weak will in a broader sense, also as correlated with the lack of patience, which may not be reducible to the category of irresoluteness. 3 I would like to give my thanks to Robert C. Roberts for turning my attention to this issue. Moral neutrality of the will power virtues makes it difficult to think of virtue as a normative category, and to ascribe it a positive, evaluative character. Maybe then, in such cases, we should not speak of virtues at all. The mere efficacy cannot be treated as something desirable in itself. Analogically with vices such as lack of self-control, laziness, or lack of perseverance. Just as the will power may help one do evil, these vices may prevent one from causing morally disastrous results. In the case of a person who wants to do evil, e.g., prepares a terrorist attack, her laziness and lack of perseverance could be desirable as because of them, more people's lives would be saved. It seems that willpower virtues, although they are necessary for acquiring other virtues, they are not sufficient to generate a morally good action. They are just means to a morally good action, and as such, they may be treated as merely instrumental and not substantial virtues. 4 In Aristotle's ethics, the problem of the moral neutrality of will power virtues is overcome by accepting the doctrine of the unity of virtues consisting of two claims. According to the first one, "it is not possible to be good in the strict sense without practical wisdom, nor practically wise without moral virtue" (EN 1144b 30-32). Most (if not all) contemporary virtue ethicists accept this claim (Snow 2008;Kamtekar 2004). According to the other, a more controversial claim, it is impossible to narrowly specialize in perfecting some ethical virtues without exemplifying all the other ethical virtues. One either has all of them or has none. Developing some, selected virtues independently of the development of the rest of virtues is not possible (EN1144b33-1145a1).
Thus, the mere ability to overcome one's fear or one's perseverance cannot be called virtues, unless they serve to realize the goal that would be chosen by a person of practical wisdom (who would also be benevolent, generous, and just). For this very reason, we cannot use the term virtuous (e.g., courageous in the proper sense of the term) to describe a terrorist or his act. According to Aristotle, a man of practical wisdom can deliberate well about what is good and expedient for himself, or about what sorts of things conduce to the good life in general [EN 1140a26-27]. He understands good life as eudaimonia, i.e., perfecting oneself as a human being; and this includes acquiring ethical virtues.
The majority of virtue ethicists reject this doctrine, although some still defend it (Sherman 1987, Russel 2009). From the Aristotelian perspective, the will power virtues (e.g., self-control, perseverance, moderation) could be called virtues only if accompanied by practical wisdom and other strictly ethical virtues. Such an approach, however, does not meet the condition of minimal psychological realism: nobody seems able to instantiate all the virtues, and thus, no one can be called virtuous in the proper sense of the term (Badhwar 1996;Wolf 2007). The condition of minimal psychological realism is not arbitrary but based on a reasonably uncontroversial intuition that "ought implies can." Moral obligation to become virtuous cannot be beyond our natural human powers (Flanagan 1993).
However, contemporary virtue ethicists, although skeptical about the strong, "all or nothing" interpretation of the unity of virtues, acknowledge that, apart from the virtues of will power, we also need to develop practical wisdom 5 and so-called substantial virtues (e.g., honesty, compassion, justice, generosity, and so forth). The emphasis on practical wisdom can be found especially in the Aristotelian doctrine of the golden mean, widely accepted by contemporary followers of the Greek philosopher (Roberts 1984;Steutel 1999). In Aristotle's view, a virtuous person is a man who takes a proper attitude to passions, and the measure of neither too much, nor too little [EN 1105b28-29]. The person properly controlling her appetites is not the one who entirely gets rid of them but the one who moderates them accordingly to circumstances (Comte-Sponville 2003, p. 39). A perseverant person consistently realizes her plans, however, not at any cost. Such a person can estimate whether her plans make sense in new, ever-changing circumstances, and, if necessary, can let go of them. The same may with a patient person: she is not someone endlessly allowing other people to use or abuse her. Similarly, a person with the virtue of self-control knows the proper measure beyond which self-control becomes its lack or total apathy, complete non-existence of any feelings or emotions. Excessive perseverance or its total absence, in turn, become singleminded obstinance or a quick surrender whenever one faces any obstacles.
Practical wisdom is not just any kind of cleverness, but one directed towards the realization of moral goodness, eudaimonia (EN1144a-b). One cannot improve it without perfecting the substantial virtues, which Roberts characterizes as "psychological embodiment of ethical rules and emotions." In contrast to perseverance, selfcontrol, or patience, substantial virtues assume specific patterns of moral judgment, emotions, and behavior (Roberts 1984, p. 229). An honest person cannot steal, lie, or take credit for things she has not done. A compassionate person will never be indifferent to the suffering of others. Moreover, a generous one will not pay scrupulous attention to the mistakes that other people make. Actions resulting from such virtues are morally good because such is the essences of those virtues: people who possess them have noble motives. Attending and perfecting substantial virtues may warrant that the will power virtues be not used to achieve evil goals. It must be noted, however, that perfecting moral virtues also depends on attending the will power virtues. Without self-control, perseverance, patience, and so on, moral development (or, more generally, human flourishing) would be impossible. Nevertheless, the value of these virtues is merely instrumental; equally well, they can serve human development and destruction. Substantial virtues, in contrast, are of intrinsic value; they are goods in themselves (Hare 1981, 203-205).

The Nature of Will Power Virtues
In recent years, due to situationist criticism, the problem of existence and nature of virtues has become a subject of heated discussion. Situationists have put into question the empirical adequacy of the traditional understanding of virtues as global traits of character manifesting consistently across all kinds of behavior of a given person. In a vast number of publications, the critics referred to empirical studies that supposedly prove that, overall, people behave inconsistently, and thus, ascribing any globally conceived traits of character to them is nothing but a result of attribution error (Doris 2002). One of the strategies to defend virtue against this criticism is to show similarities between the doubted virtues and unquestionable practical skills of experts, such as the ability to skillfully play an instrument, high level of surgery skills, or sports dexterity (Annas 2011; Sticher 2018). This analogy seems justified for a few reasons. Firstly, virtues, similarly to practical skills, are not inborn but acquired. Secondly, the process of acquiring virtues is realized through habituation. Thirdly, virtues cannot be reduced to simple habits because acting on virtues requires the conscious activity of practical intelligence. Just as a highly qualified surgeon or violinist do not limit themselves in their professional performances to the automatic (or passive) realization of the previously learned actions, but actively use their skills and flexibly react to the needs of their situation, so does a virtuous person go beyond automatic, fixed responses and react flexibly to a changing circumstances. Fourthly, all actions based on practical skills, although they do not have global character, are not realized in all possible situational contexts, they are not local to such an extent that they would be limited to a very narrow type of situation. Situationists allow merely for very narrow features and dispositions of character (Doris 2002). However, as the defenders of virtue notice, if nobody questions the existence of actions based on practical skills, why would we have to question the existence of virtues and actions that flow out of virtues (Annas 2011;Snow 2008;Sticher 2018).
Interestingly, comparison virtues and skills caught the attention of virtue ethicists long before the debate with situationists. The adherents of virtue discussed a significant difference between virtues and practical skills (Wallace 1978;Roberts 1984;Meilaender 1984;Zagzebski 1996). The acknowledgment of the difference can even be traced back to Aristotle. The virtues of will power, indeed, look very similar to skills, but because this similarity might be deceptive it is worth taking a closer look at their nature to find out whether they can be reduced to the genre of skills.
Robert Roberts maintains that whenever people make efforts, skills are required; and because virtues such as self-control, perseverance, patience require the efforts of the will to resist the adverse inclinations, Roberts sees them as capacities to a large extent, similar to any other kinds of skills (Roberts 1984). Nevertheless, in his view, they cannot be entirely reduced to skills. Although similar to skills, they are also importantly different, the main difference being such that, unlike will power virtues, regular skills are always connected with certain technical capacities (Wallace 1978, p. 44, Zagzebski 1996. However, psychologists have worked out certain techniques (I will say more about them later) helping overcome various addictions (to alcohol, food, work, etc.); and these techniques, to a large extent, consist of strengthening self-control, perseverance, or patience (Baumeister and Tierney 2011). Similar techniques have been invented in psychological coaching to support people in achieving their professional goals in areas such as sports, management, or academic career. Thus, it may seem, strengthening will power virtues is not that different from similar development of skills essential for playing chess, musical instruments, or participating in medical practices (Roberts 1984, p. 242-246, Sticher 2018.
Still, regular skills, apart from techniques, include also additionally some theoretical knowledge, highly advanced expertise at times. One cannot be a chess, musical, or medical expert without special knowledge. To be a skillful violin player, one needs to know how to read musical notes, what harmony consists of; to be an expert medical surgeon, one needs to have extensive knowledge of human physiology, chemistry, etc. One part of this knowledge is specific to a given domain; another part reaches beyond, into other fields of expertise. Because the will power virtues apply to various areas of life, it is hard to speak of any specialist knowledge required for perfecting these virtues. They are usually perfected as means or side effects of the realization of other goals, e.g., becoming a skillful player, liberating from an unwanted addiction, etc.. Focusing on a particular form of will power for its own sake, e.g., on the ability to control emotional impulses or thoughts, does not make much sense.
Because will power virtues have a more extensive range of impact than particular practical skills, they also more profoundly define our individual character. Not being skillful in playing an instrument, or playing football does not have a significant impact on one's overall character. Instead of playing the violin, one can be good at writing poetry, or gardening without major consequences to one's life. However, if one neglected will power virtues, the consequences would be profound. The lack of self-control, perseverance, or the lack of patience are much more serious and make it difficult, if not impossible, to function well in many areas of human life (Broadie 1991, 89-90, Zagzebski 1996. Another essential difference lies in how we judge the decisions not to use will power, and how we estimate decisions not to use practical skills. If a violin virtuoso refuses to show her mastery despite a good opportunity to do so, it does not affect her musical skills in any significant way. The same could be said of a skillful singer, writer, or sportsman. By refusing to show their skills, they would not lose or diminish their skills. Nor would they be denied such skills because of the refusal. In the case of virtues, however, one cannot suspend their use just because one does not feel like doing it in given circumstances. Refusing to control one's emotions when the circumstances call for it would mean lacking self-control. Refusal to act in a virtuous way signifies the lack of a given virtue (Meilaender 1984, 6-10).
Thus, taking into account all these differences between virtues, including will power virtues and practical skills, it seems that identifying will power virtues with skills is a kind of oversimplification. Dispositions such as self-control, perseverance, patience are more fundamental than skills. Unlike skills, they have an essential influence on our actions in nearly every field of our life. It is hard to imagine the realization of any life plans without having these dispositions, at least on some fundamental level. Similarly, the virtues of will power are also necessary for one's moral development; without them, one would not be able to overcome laziness, harmful, or destructive emotions and desires. Now, what can we learn about the will power virtues from empirical studies? Do the ethical considerations go along with the psychological findings?

Strong Will from a Psychological Perspective
We can come across quite a few studies in experimental psychology over self-control and selfregulation, by which psychologists mean the ability to change or modify one's reactions. Of course, because self-control and self-regulation do not exhaust the list of will power virtues, one can ask whether such studies are a reliable basis for drawing general conclusions about will power virtues. Nevertheless, such studies do allow for the recognition of certain psychological mechanisms that play a role in one's development of the will power virtues as well as in actions that are based on the will power virtues.
The widely known experiment which started the golden age of self-control studies was the so-called Marshmellow Experiment by Walter Mischel. Mischel understood self-control as the capacity to delay gratification. He studied few-year-old children, trying to find out if they were able to refrain from eating one cookie for 15 min while knowing the prize for doing so would be two cookies. After many years Mischel compared the results of this experiment with the data of how those little subjects lived later on as adults. He noticed a significant correlation between their ability to delay gratification at childhood and their achievements in adult lives. Those who, as children, were able to refrain from instant eating a candy, on average, had better marks at school, higher scores in final exams, better jobs, and higher wages in later stages of life. They also had fewer problems with drug addictions, obesity, or law-abidingness (Mischel 1974;Mischel et al. 1988). 6 Mischel's studies confirmed the fundamental significance of selfcontrol and its global (i.e., covering all the domains of human life) character.

Baumeister's Understanding of Strong Will
The results of Michel's studies inspired Roy Baumeister, a highly esteemed psychologist. Before hearing about Michel's research, he was, like most psychologists at the time, skeptical of the thesis that people can consciously control themselves. However, after getting engaged in extensive research over self-control, he went on to maintain that most significant social and personal problems, such as violence, compulsive expenditures of money, unhealthy diet, or excessive alcohol consumption, resulted from the lack of self-control (Baumeister et al. 1994). Other researchers also confirm the importance of self-regulation. They point at a high correlation between self-control and other positively evaluated personal features such as kindness, reasonableness, cooperativeness, high competence, or intelligence. In contrast to that, lacking the ability to delay gratification is highly correlated with a high level of aggression, low level of stress-resistance skills, or the lack of endurance (Founder et al. 1983).
Baumeister claims that people can gain considerably great resources of self-control (the control of their thoughts, emotions, impulses, or behavior) if they only care sufficiently enough. Basing on his studies, Baumeister questions contemporary tendencies to treat people with no self-control as mere victims of overwhelming impulses, or as victims forced to unwanted behavior. Such arguments are often put forward by lawyers in defense of their clients. Baumeister argues that, apart from some exceptions, people take an active part in destroying (or undermining) their ability of self-regulation; firstly, by minor acts of negligence, later by indulging their impulses, and finally, by total acquiescence and passive surrender (Baumeister et al. 1994; Baumeister and Tierney 2011). 6 Neil Levy argues interestingly that the ability to delay gratification does not have to do anything with strong will but rather it is correlated with the ability to avoid temptation. In his view, Mischel discovered a completely different phenomenon than the strenght of will in his experiment. The ability to avoid temptations has nothing to do with strengthenig one's will. Applying various techniques of avoiding temptation, e.g., not going to Candy shops, buying small portions of ice-cream, does not require any muscle of the will, or struggling. And this is what the children in Mischel's experiment did: they closed their eyes, sang songs, played with their hands (2017). One may wonder, however, whether the mere searching the ways to avoid temptation does not presuppose already having a significant level of will power consisting of the ability to resist a given temptation (to eat more sweets, smoke or burst with anger). Looking for the ways to resist temptations already presupposes a strong will to do it.
Self-control involves regulating many overlapping processes that can mutually interfere, fortify, suppress, or substitute one another. The first precondition of starting the process of selfcontrol is, according to Baumeister, defining the goals and ideals which one wants to realize in life. Secondly, one needs to reflect on one's current modes of reacting. If they fit the defined goals, they should be maintained; if they do not fit the chosen goals, they should be changed. Thirdly, one needs to know how to break already solidified unwanted modes of reaction and establish new ones that would agree with the accepted standards. Baumeister describes such a process in terms of a battle between various forces within us. In the context of morality, we can speak of a struggle between the temptation to choose the easier way (e.g., by telling a lie, breaking a promise) and the wish to do what is right (Baumeister et al. 1994).
Baumeister compares the ability of self-regulation to the strength of will. In his view, a strong will is like a muscle which, through special techniques, can be worked out and become stronger. The best strategy is to set goals which that gradually, proportionately to one's actual condition, grow more, and more challenging to achieve. Systematic training may thus lead to unbelievable effects. The best example of enhancing one's self-control is American illusionist David Blain who, thanks to proper training, was able to go beyond what seems to be human physiological boundaries; he was able to hold his breath, stay awake, refrain from eating for an extremely long time. Such unusual examples show how great possibilities there are in human nature when it comes to self-control. Systematic training allows one to achieve ambitious goals in various domains: professional work, overcoming addictions, sports, etc. (Baumeister and Tierney 2011).
The psychological description of self-control is, in many respects, consonant with what philosophers have to say about the virtues of will-power. Both groups speak of acquired capabilities. They are flexible enough to be either enhanced via proper training or lost due to negligence and surrendering to various internal forces (emotions, feelings, spontaneous thoughts) or external influences incongruent with the agent's goals. Psychologists, as well as philosophers, underlie the significant role of self-control in various domains of human life. They (or at least many of them) confirm that self-control is a necessary condition for the realizations of our life plans.

Ego Depletion
The results of Baumeister and his colleagues show that the will, just as every muscle, gets tired while working, and when this happens we deal with the phenomenon of will depletion. One cannot infinitely control oneself because self-control is energy-consuming (Baumeister et al. 1998). A similar phenomenon, but concerning our cognitive capacities, such as conscious attention and reflexive thinking, has been described by D. Kahneman (Kahneman 2011). Depleted will manifests with weakened self-control and hyphened emotional experiences. It becomes more challenging to resist emotional influences: not to become exalted, euphoric, disappointed, or depressed because of a trivial reason. Our ability to make decisions rapidly becomes weakened, and we easily get influenced by external factors, e.g., situation (Baumeister and Tierney 2011). The effect of a depleted ego and will is something natural, i.e., physiological. Baumeister claims that one can enlarge the resources of self-control, but the problem of will depletion cannot be eliminated.
The idea of will depletion does not quite fit the traditional virtue approach. Aristotle, as well as many of his contemporary followers, thought that a virtuous man could act against incongruent appetites tirelessly and without effort. The virtues of such a man are his second nature. He does not have to struggle because whatever would oppose virtue simply does not attract him anymore (Annas 1993, 54-55). However, the model of a virtuous man is just an ideal towards which one may stride but never fully accomplish. Most ordinary people have to struggle with their temptations in this respect.
Basing on his long-time research, Baumeister gives us some clues about how to defend against the depletion of ego and minimize the negative results of this process. The very consciousness of this process and the knowledge of our physiology are helpful. Firstly, the research shows a high correlation between losing self-control and lack of glucose (Gailliot and Baumeister 2007) and the deficit of sleep (Baumeister and Tierney 2011). Thus, if we do not want to avoid losing self-control, one thing we can do is to care for our physical fitness. Secondly, as far as it is possible, we should avoid making important decisions if we are exhausted, upset, do not have enough time, or are emotionally excited. Thirdly, and probably the most importantly, we need to previously elaborate appropriate behavioral mechanisms (i.e., habits) that can be trusted when they take control of our behavior. Baumeister maintains that, paradoxically, habits increase our self-control because they enhance thinking processes and behavior, and they require less energy than conscious efforts. Of course, the very elaboration of good habits is energy-consuming, but once the habits are established it will be much easier to live by our goals and standards. Studies confirm that the best students and workers owe their successes to adequately established habits (Baumeister et al. 1994;Boice 2000).
Ascribing habits a crucial role in the reduction of the will depletion has its counterpart in the philosophical accounts of virtues. Although no virtue ethicists would agree to reduce virtues to automatized behavior, we cannot understand virtues without encompassing this habitual automaticity. We say that virtues are excellences because they allow us to respond efficiently to occurrent moral reasons. They result from moral practice, repeated actions, emulation of experts, and deep reflection over moral matters. Thus, in obvious situations, which do not require any special attention or deepened reflection, analogically to other domains of practice where expert skills have their application, a virtuous person can automatically respond to situations and occurrent moral reasons. A truthful person usually tells the truth; a helpful person brings help to the needy ones, the one who is magnanimous forgives. I do not mean that such people all the time act thoughtlessly and mechanically. The one who has the virtue of truthfulness does not blindly say the truth to everyone, even in situations when others are not entitled to it. The helpful one does not help when doing so may bring about injustice or grievance. The generous does not forgive if such forgiveness would spoil the wrongdoer and encourage him to do further evil. Thus, a virtuous person, just like an expert, does not neglect the use of reason. On the contrary, his practical wisdom (moral expertise) allows him to face the most difficult cases. But in ordinary situations, there is no need to think hard; moral reasons, as well as right choices, are seen effortlessly by a virtuous person. This effortlessness of the acquired mechanisms allows her to save time and energy when making moral decisions. Moreover, the function of these automatic mechanisms finds its confirmation in contemporary psychology.
When working on moral character, one can use various techniques of enhancing selfcontrol that were developed from empirical studies and now are recommended by psychologists. These techniques usually apply to fight various types of addictions (such as alcohol addiction, hazard, compulsive eating). They are also successfully used to motivate people in their work over developing the skills necessary for work, health, or sports. The studies suggest that we first need to define our mutually consistent goals, i.e., ones that do not conflict with one another. Let these goals be ambitious and far-reaching, but they must be analyzable into many relatively easy to reach steps the realization of which is not too demanding and gives satisfaction. Such satisfaction, in turn, motivates to go on to further steps (Bandura 1977;Baumeister and Tierney 2011). Secondly, we can see from the studies that social support is also a strong motivational factor. It is a useful strategy to announce publicly what our life goals, ideals, or principles are. It is desirable that our audience are people who are close to us, who will support us and, on occasions, if need be, control us. Thirdly, it is also worth defining clear lines (i.e., clear do's and don'ts) so as not to lose self-control in particular situations of temptation. To a person who is, say, addicted to alcohol such a 'clear line' would be 'don't drink at all -not even one bit.' This is how a prudent person, aware of her weaknesses, would act. She would not risk unnecessary temptation. Blurred lines are easier to cross (Gollwitzer and Oettingen 2011).
Another, very efficient technique of directing one's behavior is so-called self-reinforcement. Its role is to keep a high level of motivation to do what is right until the first desired effects appear; they give us the necessary motivation to continue our work on self-control. Selfreinforcement may have both positive and negative character. One can motivate oneself through conditional rewards, particularly when long, persistent, and systematic work is required. Facing difficulties is always easier if small successes are accompanied by some rewards (even if symbolic ones) (Bandura 1977).
All those techniques can be accepted in the process of perfecting moral character, i.e., strengthening virtues (including the virtues of will power). They also prove useful in the practice of developing practical skills. Acquiring virtues and acquiring practical skills, from the psychological point of view, are very similar, especially when having motivational force in mind. Both becoming skillful on the expert's level, and perfecting virtues, are long and complex processesone can easily get discouraged before becoming an expert or a virtuous person.

Controversies
Baumeister himself maintains that the control resources grow regardless of what kind of exercise (which requires self-control) is taken up. The studies on self-control show that training one's own will in one field of activity has positive results in other fields of activity (e.g., healthier eating behaviour, or controlling one's violent behavior, sports, controlling expenditures, smoking or drinking behaviour (Muraven et al. 1999;Cranwell et al. 2014;Finkel et al. 2009;Muraven 2010a, b, Oaten andCheng 2006a, b). Besides, the will of the subjects became depleted much slower than that of the subjects in the control group (Oaten and Cheng 2006a, b).
However, we can easily find examples of persons who very well control their behavior in one domain while they cannot control themselves in other domains. History is full of cases of politicians, athletes, or scientists who made great professional careers, which must have required much self-control, while turned out to be unfaithful in marriages, falling to erotic temptations that later on they regretted. Suffice to mention the famous golfer Tiger Woods, or Bill Clinton, former president of the US. Nevertheless, these examples do not have to undermine Baumeister's thesis about the domain-general resources and strategies of self-control. Failures to act in the right way may result not from one's lack of self-control but from one's wrong understanding of what one ought to do. One may simply not perceive his actions as harming or immoral and thus may have stronger impulses to engage in impulsive sexual behavior than to engage in other impulsive behaviors (Duckworth and Tsukayama 2015).
In recent time, there have appeared some criticism of Baumeister's theory of self-control, that denies the existence of particular, biological, and internal resources of self-control to be found in each individual. Baumeister does not understand these resources merely metaphorically but takes them to be something physical and concrete, something that can be measured. Together with Gailliot, Baumeister made a hypothesis that it is glucose that can be strictly correlated with effective self-control and will depletion (Gailliot and Baumeister 2007). They are now heavily criticized because their hypothesis contradicts well-grounded knowledge on the metabolization of glucose in the brain (Beedie and Lane 2011;Kurzban 2010). The brain uses only a small portion of the glucose that is metabolized by the whole body, and it is only in extreme situations that the body is not able to provide enough glucose to ensure mental processes. Hence, it is highly impossible that performing a short-time task which requires one's self-control (e.g., squeezing a handgrip) would lead to such a serious fall of glucose level that later on one would not be able to perform such tasks as solving acronyms, which was identified by Baumeister as free will depletion effect (Kurzban 2010). The question of sources and reserves of self-control is not at the moment resolved on the ground of empirical studies.
The ego-depletion phenomenon, as I have mentioned earlier, poses a problem to virtue ethics, which assumes, and it is one of its main assumptions, that having a virtue warrants a morally good action. Meanwhile, both Baumeister and Kahneman write that although one can enlarge one's self-control or attention resources, they are not limitless, and, at some point, everyone would reach the level of ego depletion (Baumeister and Tierney 2011, Kahneman 2011). Also, several historical data confirm that many people, when deprived of a sufficient amount of food, drink, or sleep, as well as when living under significant and long term stress, have their abilities to control their thoughts, feelings, or behavior dramatically weakened. A good example of that could be Jewish ghettos during WWII. The same could be said of the subjects in Philip Zimbardo's experiment who were isolated from the external world and had to face the pressure of an imposed social role of the prisoners and guards (Zimbardo 2008).
But then, we may easily point at the cases of persons who, despite being situated in very similar, if not the same, circumstances, were able to do outstanding things that required vast resources of self-control. One such example is a Polish nurse, Irena Sendlerowa, who saved a high number of Jewish children by smuggling them out of the Jewish Ghetto in Warsaw when any help to Jews was punished with the death of not only the person who helped but also all her close family members. Sendlerowa said she could not imagine acting otherwise. Another example is Jan Karski, who, while gathering evidence of the extermination of Jews carried out by the Germans in occupied Poland, had to undertake numerous dangerous actions risking his life. Father Maximilian Kolbe is still another example. He volunteered to be selected to starve to death in Auschwitz to save the life of another man. We could go on with this list much, much longer.
Moreover, even the experimental data in moral psychology show that ego depletion is strongly correlated with the level of internal motivation of a subject. Persons who follow their strong beliefs have their clearly defined goals, or a system of values do not easily follow external motivation, e.g., the desire to get rewarded. In their case, the ego-depletion effect occurred much more rarely and to a lesser degree than in the control groups (Muraven et al. 2007), and in some cases, ego-depletion was not observed at all (Moller et al. 2006). This may suggest that the reservoir of will power strongly depends on internal motivation. The more we identify with certain norms and values, the more we are motivated to follow them. This correlation is confirmed by the studies which show that efficient self-regulation of subjects was tied with their strong views on values and their strong identification with the performed task, its meaning, and significance (Schmeichel and Vohs 2009).

Summary
Virtue ethicists, influenced by the situationist criticism, started to look more closely at the results of empirical studies in the field of psychology. Although the empirical data are not sufficient to draw normative conclusions that are formed within ethics, paying attention to them helps bring a lot of useful issues into ethical discussions, including the debates over the nature, acquiring and development of virtues. The empirical data allow virtue ethicists to argue that their central claims can be reconciled with the results of empirical studies in moral psychology. Firstly, psychological studies show that people have the ability to self-control and self-regulation and that the use of specific techniques can enlarge its reservoir. Thus, the studies confirm one of the key claims of virtue ethics, namely that it is possible to acquire and develop virtues. Secondly, psychologists notice that one cannot overestimate the ability of selfcontrol and self-regulation. They are decisive to our realization of our life plans, successes in various fields of human practice. For this reason training the will power, advocated by virtue philosophers, finds also support from the side of psychologists. Thirdly, there are many selfregulation techniques, used to fight various addictions, that can also be applied to develop virtues. Fourthly, the ability of self-control and self-regulation can be seen as wide, fundamental dispositions that unlike other kinds of practical skills find application in all domains of human life. As such, they cannot be reduced to the category of mere skills. Fifthly, the phenomenon of ego-depletion, which might be perceived as falsifying the existence of virtues understood as stable dispositions to morally good actions, does not take place when the agent is strongly motivated to a certain type of action. Virtue ethicists emphasize that virtuous action is not merely an action in accordance with moral obligation, but it has its source in a strong motivation of the agent to act in a morally good way. A person who perfects her self-control by following her internal motives and the desire to become a better person is able to control her desires, emotions, and impulses that go against her goals, even in extreme situations. The moral heroes mentioned above in this article are the best example of that truth.
Empirical data, however, do not add anything to the discussions over the normative character of virtues. They do not allow for resolving which of the stable and acquired dispositions may be classified as substantial virtues and are merely instrumental virtues. Taking into account that the will power virtues, also called executive virtues, lead to both morally good and evil action, they should be viewed as merely instrumental virtues.
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