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Medieval Philosophy

Aquinas on Conscience, the Virtues,
and Weakness of Will

Douglas C. Langston
New College of the University of South Florida

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ABSTRACT: The intellectualistic analysis of conscience Aquinas provides appears to regard conscience as mechanistic and undynamic. Such understanding fails to place Aquinas’s remarks on conscience in the context of the virtue ethics he offers in the Summa and his Commentary on the Nicomachean Ethics. In fact, there is an intricate connection between the virtues and conscience in Aquinas’s thought, and this connection relates directly to his remarks on weakness of will. His connecting conscience to issues in Aristotelian virtue ethics affects subsequent discussions of conscience in significant ways.

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At the risk of over-simplification, one can talk of two views of conscience and synderesis emerging from the Middle Ages: a voluntarist view associated with Bonaventure and an intellectualist one connected with Aquinas. Bonaventure's voluntaristic view of synderesis and conscience presents synderesis as the drive to the good and places it in the appetitive faculty. It also sees conscience as a dynamic faculty generating general rules of behavior. In contrast, Aquinas claims that synderesis is part of the rational part of human agents. It is a natural disposition of the human mind by which we apprehend without inquiry the basic principles of behavior; it is thus parallel to the disposition by which we apprehend without inquiry the basic principles of the theoretical disciplines.(1) Once the basic principles are apprehended and become part of synderesis, the conscience, also in the rational part, applies these first principles to particular situations. Aquinas holds that synderesis is never mistaken; he claims, in addition, that the first principles of synderesis are necessarily true. A human agent does evil when the conscience makes mistakes in its applications of synderesis through invalid reasoning or by joining a first principle with a false premiss and deriving a false conclusion. Like Bonaventure, Aquinas holds that conscience is binding, but he treats the error of following a mistaken conscience in a slightly different way. If the conscience has made a factual mistake, e.g. the agent does not know that a particular case falls under a general rule, the mistaken conscience is not culpable. If, however, the mistake comes from ignorance of a law the agent should know, the agent is culpable.(2) It is crucial for correctly appreciating Aquinas's views about synderesis and conscience that we place them in the context of his ethical views as a whole as presented in his Summa Theologiae. The work is divided into three parts and the first part of the second part is a systematic treatment of ethics. In general, it presents a teleological and eudaemonistic ethics that is, in the main, Aristotelian.(3) For the most part, it presents prudence is as the most important moral virtue, for it perfects the practical activity of reason and directs the other virtues.(4) Prudence is defined as right reason applied to human conduct.(5) This is, however, a misleading description of prudence, since it presents it as far more narrow in scope than Aquinas believes it to be. A much better (though considerably longer) description of prudence is found in the response section of Summa Theologiae, I-II, q. 58, article 5: "Can There Be Intellectual Virtue Without Moral Virtue." Here Aquinas tells us: All other intellectual virtues can exist without moral virtue, but there cannot be prudence without moral virtue. The reason for this is that prudence is right reasoning about what is to be done—and this not only in general, but also in particular, in respect to which man acts. Now right reasoning requires principles from which the reasoning proceeds. And reasoning about particulars must proceed not only from universal principles but from particular principles as well. As to universal principles about things to be done, man is rightly disposed by the natural understanding of principles, whereby he recognizes that no evil is to be done; or again by some practical science. But this is not enough for right reasoning about particular cases. For it sometimes happens that such a universal principle known by understanding or through some science, is perverted in a particular case by some passion; for example, to a person very desirous of some-thing when the desire overcomes him, the object of it seems good to him, although it is contrary to the universal judgment of his reason.

Consequently, just as man is disposed rightly with regard to universal principles by natural understanding or by the habit of science, so in order to be rightly disposed with regard to the particular principles concerning things to be done, which are ends or goals, he must be perfected by certain habits, so that it becomes connatural, as it were, to him to judge rightly about an end. This comes about through moral virtue, for the virtuous person judges about the end of virtue rightly, since "such as a man is, so does the end seem to him." Hence in order to reason rightly about what is to be done, which is prudence, man must have moral virtue.(6) In this passage, Aquinas connects prudence with the correct perception of individual circumstances. In fact, he links prudence to the problem of weakness of will and to the development of particular principles of behavior. Although general moral principles, according to Aquinas, are given through the synderesis, these principles are rather empty, consisting of general statements like: "Do good and avoid evil" and "Obey God." For human activity, more content-rich principles are required. Aquinas talks about these principles in various places.(7) He claims that they are not innate, but are derived from experience and instruction. In his discussion of the role of prudence in Aquinas's ethics, Daniel Nelson calls them secondary principles, and he claims that they are developed through prudence:

Once again, these naturally known higher principles, the ends of human action, are so general as to be empty of material content. The content, which depends on prudence and the virtues, is learned. I am arguing that what Thomas sometimes calls first universal principles of practical reason or natural law play the explanatory role I have described, while the secondary principles, which are acquired over time, guide conduct. The primary principles are known through synderesis, while the secondary principles are the concern of prudence.(8)

With the mention of synderesis, we are, of course, brought back to issues concerning conscience. In fact, conscience is discussed in the first part of the second part of the Summa Theologiae (I-II, question 19, articles 5 and 6). Here Aquinas discusses the binding and excusing powers of a mistaken conscience. In the two articles, he defines 'conscience' as the "application of knowledge to activity."(9) There appear to be a number of links between conscience and prudence. Not only is prudence connected with carrying out the dictates of conscience, but prudence is also connected with the knowledge that is applied to activities.(10) The rules that apply to particular cases come from the secondary principles derived from prudence, and the apprehension of particular circumstances, which determines what secondary rules the circumstances fall under, is also a product of prudence. It seems clear, then, that for Aquinas, prudence works in tandem with conscience and synderesis. Although conscience may be understood by Aquinas to be simply an application of principles to individual cases, the richer activities of conscience found in Bonaventure's discussion of conscience are placed by him into issues surrounding prudence.

Aquinas also sees a close connection among conscience, synderesis, the virtues, and weakness of will. As one of the best commentators on Aristotle's Nicomachean Ethics, Thomas Aquinas was deeply interested in the problem of weakness of will.(11) His interest was also informed by Christian views about sin and the will, developed in large part out of Augustine's concern for these issues.(12) In line with renewed interest in Aristotle's views about weakness of will there has been increased interest recently in Aquinas's views about incontinence.(13) Of particular note is the work of Bonnie Kent and Risto Saarinen. In her article, "Transitory Vice: Thomas Aquinas on Incontinence," Kent argues that Aquinas's analysis of incontinence differs from Aristotle's view of weakness of will in two critical ways.(14) In the first place, the incontinent for Aquinas judges his incontinent act to be good. In the second place, the incontinent, according to Aquinas, chooses the incontinent act he performs. In Kent's opinion, these two differences show up in both Aquinas's commentary on Aristotle's Nicomachean Ethics and in his own views about incontinence.(15) In Kent's eyes the second point of divergence is the more significant.(16)

In his commentary on the Nicomachean Ethics, Aquinas is very careful to indicate that Aristotle denies that the incontinent acts from choice. He never asserts that Aristotle believes that the incontinent chooses his action. But, according to Kent, it is likely that Aquinas saw Aristotle's analysis here to be "correct but incomplete."(17) In his own theological works, Aquinas claims that the incontinent chooses to act as he does. But this claim seems in conflict with Aquinas's statement that the incontinent sins from passion or weakness while the intemperate sins from choice.(18) Kent, however, resolves the conflict by pointing out that Aquinas distinguishes two different senses of choice: peccare ex electione (sinning from choice) and peccare eligens (sinning while choosing). According to Aquinas, the incontinent chooses his incontinent action (peccare eligens) but his act is not from choice (peccare ex electione). In elaboration of the distinction, Kent tells us:

Incontinent action is chosen, but it is not done from choice. By an act done "from choice" Thomas means an act in accordance with the agent's moral disposition and hence reflecting his opinion of what is good in general. The basis for this might be Ethics VI, where Aristotle says that there is no choice without moral character (1139a32-35).

Incontinent action, which is against choice, must thus be somehow "out of character." Aristotle's comparison between incontinence and epilepsy lends support to this idea. The incontinent is not consistently indulging his appetites any more than the epileptic is in a continuous seizure. Both function well for the most part, suffering only from intermittent flareups.(19) Since the incontinent man wills to perform his incontinent act, he chooses the act in the sense of "peccare eligens." The intemperate man does the same. But since the incontinent's selection of the incontinent action is "out of character," he does not do the action from choice in the sense of "peccare ex electione." The intemperate man, on the other hand, has developed a lifestyle of choosing wrong actions and his choice of a wrong action is from a habit he has freely developed. The intemperate's choice reflects his character and so is a choice in the sense of "peccare ex electione." The contrast here between the incontinent man and the intemperate man explains why Aquinas regards the intemperate man as subject to a habitual vice and the incontinent man as suffering from transitory vice.

In reviewing Kent's views, Risto Saarinen expresses considerable agreement with Kent, but he thinks he has a better explanation of how the incontinent chooses the incontinent action without acting out of choice. He offers a "two-step explanation of akrasia."(20) Like Kent, Saarinen proposes (following Aquinas) that we think of the incontinent man as possessing two general principles: one that forbids the action, the other that permits the action. When the incontinent person is faced with a particular opportunity, "concupiscence places this minor premise under the wrong major proposition."(21) According to Saarinen, the placing of the minor premise under the wrong major is the first step of a two-step process. This first step is "voluntary," but it is not deliberately chosen by the incontinent person. Saarinen, in fact, claims that this first step explains why Aquinas says that the incontinent person does not act wrongly in the sense of "peccare ex electione." Since the first step is not deliberately chosen (presumably because it is driven by concupiscence), it cannot be done "ex electione." Once the minor premise has been subsumed under the wrong major premise, the incontinent follows out the perverted syllogism and chooses the incontinent action. This choice after the perverted deliberation is the second step of the incontinent action, and the incontinent deliberately chooses this action. It is an action that is "eligens."

In many ways, Saarinen's proposal is best seen as an elaboration of Kent's basic analysis. He thinks that Kent has correctly analyzed the second step of an incontinent action, but he believes that there is a "first step" prior to this second step. This step occurs "contrary to the choice disposed toward the proper good."(22) This first step seems to be, essentially, perceptual; it is the point in the action where the opportunity is seen either as a desirable pleasure (contrary to the choice disposed toward the proper good) or as a forbidden object (in line with the choice disposed toward the proper good). The second step is a good deliberation, drawing the appropriate conclusion from given major and minor premises. Aquinas, in fact, emphasizes the difference between the perceptual and the deliberative in his commentary on Book VI of the Nicomachean Ethics. In Lecture IX, when discussing prudential action, Aquinas contrasts eubulia with synesis.

'Eubulia' (the topic of Lecture VIII) is "good deliberation."(23) It is characteristic of prudential people. 'Synesis' is good judgment about the things treated by prudence.(24) It is also a critical part of prudence but is not to be identified with it. Aquinas's main point in the lecture is that a prudent person must judge particulars correctly and deliberate well about these particulars so that he may act correctly. Since an incontinent person lacks prudence, it is clear that the incontinent man must be lacking in either eubulia or synesis. In fact, Aquinas's third lecture on Book VII of the Nicomachean Ethics seems to emphasize that the incontinent is lacking in synesis.

In this text, Aquinas presents incontinence as a problem in practical reasoning. At paragraph 1339, he indicates that practical reasoning involves both universal and particular propositions. In the next paragraph (1340), he makes a critical point: We should note, however, that the universal can be taken in two ways. In one way as it is in itself, as in the example, "Dry things are good for every man"; in another way as it is in a particular object, for instance, "This is a man," or "That food is dry." Therefore it is possible that a man knows, both habitually and actually, the universal considered in itself but either he does not grasp the universal considered in this particular object, i.e., the universal is not known in an habitual way, or he does not bestir himself, i.e., the universal is not actually known.(25) The issue of how a universal is seen in a particular is essential to Aquinas's explanation of the actions of the incontinent man as we can see in paragraph 1347:

On the first point the proper consideration is this – reason in the incontinent man is not so completely overcome that he is without genuine knowledge of the universal. Put it this way. The reason proposes a universal judgment forbidding an inordinate tasting of something sweet, e.g., it says that nothing sweet should be tasted outside a certain time. But the appetite proposes that every sweet thing is pleasant, something in itself desired by concupiscence. And, since in a particular case concupiscence may bind reason, the proposal is not accepted under universal reason so as to say also that this is outside the time; but it is taken under the universal aspect of concupiscence so as to say this is sweet. So the conclusion of the operation follows. In this syllogism of the incontinent man there are four propositions, as already indicated.(26)

Driven by concupiscence, the incontinent man sees an opportunity (for example, a desirable unmarried woman) as an example of the permitting rule (Pleasures should be enjoyed). Under the influence of concupiscence, he is unable to see the opportunity as an example of the correct, forbidding principle (One should not fornicate). Given his perception of the opportunity, it is not surprising that the incontinent man performs the incontinent action. But why does he see the opportunity in the way that he does? As Aquinas says, he is driven by concupiscence. The continent man, who chooses correctly, also has concupiscence. Yet, he is not driven by it as the incontinent man is. Why, then, is the incontinent man driven by concupiscence and the continent man is not? Neither Kent nor Saarinen address this important issue in their discussions of weakness of will. But it is an extremely important one. In Lecture 3 on Book III of the Nicomachean Ethics, Aquinas discusses Aristotle's views about what constitutes involuntary actions. For Aristotle, compulsion (where the active principle is outside the agent) and ignorance both render an action involuntary. In commenting on ignorance in paragraphs 505 and 506, Aquinas makes two important distinctions:

Ignorance causes an involuntary [sic], as was explained before (406-424). If, however, we are the cause of this ignorance, the ignorance will be voluntary and we will be punished for it. A man can be the cause of his own ignorance in two ways. In one way directly, by doing something, as is evident in those who get drunk and for this reason are rendered ignorant . . . In the other way a man is the cause of ignorance indirectly by reason of the fact that he does not do what he ought to do. On account of this, ignorance of the things a man can and isbound to know is considered voluntary and therefore he is punished for it . . . The same is true of those things which men do not know apparently by reason of negligence, because they could have learned. They are masters of themselves and they can be diligent and not negligent.(27)

We are responsible for our ignorance of things we should know even when this ignorance is indirect, i.e., from a failure to do what ought to be done. And this is precisely the situation of the incontinent man. When he performs his incontinent act, he is ignoring the forbidding principle he should follow because he sees the opportunity as an example of the permitting rule. He sees it in this way because he is driven by concupiscence. But he is so driven because he has neglected to develop the proper habits that would enable him to see the opportunity correctly as an example of the forbidden principle. The weakness of will the incontinent man suffers from comes from his failure to train himself adequately to see opportunities in the proper way.

Issues about habits and training, of course, connect directly to talk about the virtues. Given the context of the issue of weakness of will, i.e., that it occurs in a work advocating an ethics of virtue, it is surprising that neither Kent nor Saarinen link weakness of will with the development of the virtues. Aquinas's Commentary on the Nicomachean Ethics clearly links the two issues. As I have mentioned, Aquinas links incontinence with a failure of practical reason, and he connects eubulia and synesis with the virtue of prudence. Of course, since weakness of will is essentially a problem of the failure of prudence (or the failure to develop prudence), it is not surprising that, for Aquinas, weakness of will also involves a failure of conscience. In his discussion of the binding and excusing powers of a mistaken conscience in the Summa Theologiae [I-II, q. 19, a.5 and 6], he discusses how someone will choose what is evil because it appears good due to some factor connected with its apprehension as well as what types of ignorance excuse evil actions.(28) Aquinas's linking of conscience with prudence and the virtues in general through his concern with weakness of will departs from earlier discussions of conscience as documented, for example, by Lottin in his Psychologie et morale au XIIe et XIIIe siecles. In these discussions, the focus was on conscience and synderesis in isolation from other issues. It seems likely that Aquinas's shift is connected with the translation of the whole of the Nicomachean Ethics by William of Moerbeke, and Aquinas's interest in the whole work. Indeed, Aquinas's discussions of conscience as well as prudence are marked by constant reference to the Nicomachean Ethics. Whatever the explanation, Aquinas's shift from focusing on conscience in isolation from prudence and weakness of will is carried on in two prominent Franciscans: Duns Scotus and William Ockham.

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(1) Potts, "Conscience," p. 700.

(2) Ibid., pp. 703-04. Aquinas criticizes Bonaventure's view of conscience because he believes that it commits Bonaventure to claiming that a mistaken conscience does not bind.

(3) Nelson, Dan The Priority of Prudence (College Park: Penn State Press, 1988), pp. 32 and 36.

(4) Nelson, p. 77.

(5) Summa Theologiae, II-II, questions 48 and 49, (Volume 36, pp. 57, 79).

(6) Osterle, pp. 87-8.

(7) Summa Theologiae, II-II, question 47 (Volume 36, p. 49). Also Nelson, pp. 101-02.

(8) Nelson, p. 101.

(9) Volume 16, p. 61.

(10) See note f in Volume 16, p. 61 and Osterle, pp. 57, 78.

(11) Ralph McInerny offers this evaluation in his introduction to Aquinas's Commentary on the Nicomachean Ethics (South Bend: Dumb Ox Press, 1994).

(12) Risto Saarinen claims that Augustine's influence was important on these issues throughout the Middle Ages in his Weakness of Will in Medieval Thought, op. cit.

(13) Aquinas used 'incontinentia' for 'akrasia.' Following many others I translate 'incontinentia' as 'incontinence.'

(14) "Transitory Vice, " p. 206. Kent does not modify her views in her Virtues of the Will: The Transformation of Ethics in the Late Thirteenth Century (Washington, D. C., Catholic University of America Press, 1995).

(15) Ibid., p. 210 f.

(16) "Transitory Vice," p. 217.

(17) Ibid.

(18) Ibid., p. 207.

(19) Ibid., pp. 219-20.

(20) Weakness of Will in Medieval Thought, p. 125 f.

(21) Ibid., p. 125.

(22) Ibid., p. 129.

(23) Translation, p. 389. Aquinas seems to connect eubulia with good deliberation to good ends.

(24) Ibid., p. 391.

(25) Ibid., p. 422.

(26) Ibid., pp. 423-24.

(27) Ibid., pp. 164-65.

(28) Volume 18, responsio section of article.

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