Those who lack memory will more than likely lack docility, another integral part of prudence. St. Thomas writes:

...prudence is concerned with particular matters of action, and since such matters are of infinite variety, no one man can consider them all sufficiently; nor can this be done quickly, for it requires length of time. Hence in matters of prudence man stands in very great need of being taught by others, especially by old folk who have acquired a sane understanding of the ends in practical matters. (S.T. II-II Q 49, 3)

Docility is open-mindedness, and so it requires a recognition of one's own limitations and ready acceptance of those limits. Proud people who hope excessively in their own excellence will tend to make imprudent decisions because they fail to rely on others by virtue of their inordinate and unrealistic self-estimation. A person with false docility seeks the advice of others, but only those deemed most likely to be in agreement with him, or of those of similar depravity and who are thus unlikely to challenge the overall orientation of his life.

Shrewdness (solertia)

Shrewdness is the ability to quickly size up a situation on one's own, and so it involves the ability to pick up small clues and run with them. The shrewd are highly intuitive, subtle and discreet. A shrewd teacher, for example, will pick up subtle clues that reveal just who it is he is dealing with in his classroom and what the needs of his students really are, which allow him to determine quickly the approach best suited to their particular way of learning. The shrewd are also able to detect evil behind a mask of goodness, so as to be able to plan accordingly. Some people are dangerously unsuspecting of the motives of evil and so they miss the clues that suggest a more ominous picture. For we tend to see in others what we see in ourselves, and if our motives are good, it is hard to suspect others of malice. Moreover, excessive empathy has a way of clouding the intuitive light of solertia (Greek: phronimos).

But just as memory and docility presuppose a good will (right appetite), so too does shrewdness. It can be the case that the inability to see is rooted in a will not to see; for sometimes people would rather not think about what the clues could mean for fear of what they might discover about someone, which in turn will affect their security in some way. As the old saying goes: "There are none so blind as those who will not see". It can also be the case that a person has not learned to listen to his intuition or perhaps confuses a negative intuition with judging the heart of another and so dismisses his intuitive insights, especially negative ones. On the other hand, it is possible that a person wants to see evil where there really is none. This is not shrewdness, but suspicion, and it is often rooted in a spirit of pride.


Once a person sizes up a particular situation, he needs to be able to investigate and compare alternative possibilities and to reason well from premises to conclusions. He will need to be able to reason about what needs to be done, that is, what the best alternative or option is that will realize the right end. Prudence thus presupposes a knowledge of the basics of logical reasoning. If a person cannot see through the most common logical fallacies, he will unlikely be able to consistently make prudent decisions. Some of these common fallacies include Begging the Question, or assuming the point that needs to be proven, or Ignoring the Question, which consists in proving something other than the point to be established. False Cause consists in assuming that when one event precedes another, it is the cause of the succeeding event. The Fallacy of Part and Whole consists in attributing to a whole what belongs only to its parts (the fallacy of generalization), while the Fallacy of Misplaced Authority consists in concluding that something is true because somebody of authority, such as a medical doctor, said it. The Fallacy of Ad Hominem (directed to the man) involves the rejection of some person's position not by virtue of the argument itself, but by virtue of some unlikeable aspect of the person. The Fallacy of the Double Standard consists in applying one standard for one group or individual, and another standard for an opposing group or individual. Appeal to the People occurs when a speaker attempts to get some group to agree to a particular position by appealing solely to their bigotry, biases, and prejudices or, in some cases, merely to their desire to hear what they already believe. The Fallacy of False Analogy occurs when a person argues a position merely by drawing an analogy, without justifying the use of the analogy. And the Fallacy of Novelty assumes that what is new and current is necessarily better or an improvement upon what is older. The more adept one becomes at seeing through such deceptive reasoning, the less likely will one's decisions fall under its influence.


Foresight is the principal part of prudence, for the name itself (prudence) is derived from the Latin providential, which means "foresight". Foresight involves rightly ordering human acts to the right end. This of course presupposes that the person is ordered to the right end, which is the possession of God through knowledge and love. The greater his love for God, that is, the greater his charity, the greater will be his foresight: "Blessed are the pure in heart; for they shall see God" (Mt. 5, 8). For it is through charity that one attains God, and it is through this supernatural friendship that one grows in a connatural knowledge of God. The more a person is familiar with the city towards which he directs his steps, the more able he is to see which roads lead to that end and which roads lead away. The more a person is familiar with God, the more readily able he is to discern behaviour inconsistent with that friendship. An impure heart, that is, a love of God mixed with an inordinate love of self, will affect one's ability to "see". An inordinate love of self will cause certain alternatives to have greater appeal, but these alternatives (means) will not necessarily lead to the right end. A prudent man sees that, but the imprudent do not. And if they lack true to being memory, they will continue to fail to see it.


It is possible that acts good in themselves and suitable to the end may become unsuitable in virtue of new circumstances. Circumspection is the ability to take into account all relevant circumstances. Showing affection to your spouse through a kiss is good in itself, but it might be unsuitable in certain circumstances, such as a funeral or in a public place. Telling certain jokes might be appropriate in one setting, but inappropriate in another. Circumspection is the ability to discern which is which. This too, however, presupposes right appetite. A person lacking proper restraint (temperance) will lack thoughtfulness and the ability to consider how the people around him might be made to feel should he take a certain course of action. The lustful, for example, lack counsel and tend to act recklessly. An egoist is also less focused on others and more on himself, and so he too tends to lack proper circumspection.


Good choices can often generate bad effects. To choose not to act simply because bad consequences will likely ensue is contrary to prudence. But caution takes care to avoid those evils that are likely to result from a good act that we contemplate doing. For example, a priest who is about to speak out publicly against a piece of unjust legislation might anticipate offending members of his congregation. Out of cowardice or an inordinate love of comfort, he might choose not to say anything at all and thus risk harming others through his silence. A prudent priest, on the other hand, will speak out when not doing so will harm others, yet caution will move him to prepare his congregation with a thorough preamble so as to minimize the chances of misunderstanding. One must never do evil that good may come of it, but one may at times permit evil on condition that the action one is performing is good or indifferent, that one does not will or intend the evil effect, and that the good effects of one's action are sufficiently desirable to compensate for the allowing of the evil effect.

The Potential Parts of Prudence

Good Counsel (euboulia)

Counsel is research into the various means to the end and the circumstances. A person not entirely pure of heart, that is, whose charity is very defective, will have more options before him, poorer options that nevertheless have some appeal. The better the character, the less will these poorer options present themselves; for they will drop out of the picture very quickly. This can be compared to a person who is physically healthy and has good eating habits and one who is unhealthy with poor habits. A typical menu will be more appealing to the one with poor eating habits, while the former deliberates over a few options, the healthier options on the menu. We've all heard the expression, "Where there is a will, there is a way". Good counsel, resulting from a greater hope in and love for God, generates the energy and imagination needed to discover the best alternative to achieve the best end.

Good Judgment (synesis and gnome)

Judgment is an assent to good and suitable means. Synesis is good common sense in making judgments about what to do and what not to do in ordinary matters. It is possible to take good counsel without having good sense so as to judge well, but to judge well on what to do or not to do in the here and now requires a right mind, that is, an understanding of first principles and precepts and indirectly a just will and well disposed appetites (both concupiscible and irascible appetites). Without these, one's ideas will likely be distorted, and one's judgment regarding the best means will be defective; for as Aristotle points out, as a person is (character), so does he see. He writes:

...what seems good to a man of high moral standards is truly the object of wish, whereas a worthless man wishes anything that strikes his fancy. It is the same with the human body: people whose constitution is good find those things wholesome which really are so, while other things are wholesome for invalids, and similarly their opinions will vary as to what is bitter, sweet, hot, heavy, and so forth. (Just as a healthy man judges these matters correctly, so in moral questions) a man whose standards are high judges correctly, and in each case what is truly good will appear to him to be so. Thus, what is good and pleasant differs with different characteristics or conditions, and perhaps the chief distinction of a man of high moral standards is his ability to see the truth in each particular moral question, since he is, as it were, the standard and measure for such questions. The common run of people, however, are misled by pleasure. For though it is not the good, it seems to be, so that they choose the pleasant in the belief that it is good and avoid pain thinking that it is evil. (EN 3, 4. 1113a25-1113b)

Gnome refers to the ability to discern and apply higher laws to matters that fall outside the scope of the more common or lower rules that typically guide human action. It involves good judgment regarding exceptions to ordinary rules. For example, students ordinarily are not permitted to play walkmans in a classroom, but a possible exception to the rule might be the case of a student with a serious learning disability and who is highly sensitive to the slightest distractions. One may be able to think of similar examples on a more judicial level.


Command, which is the direct application of good counsel and judgment, is the principal act of prudence; for it cannot be said that one who takes good counsel and judges well, but fails to act, is a prudent man.

Vices Contrary to Prudence

Precipitation or impetuosity is the vice contrary to good counsel and amounts to a failure to adequately consider all available means. It may result from inordinate appetite, that is, an impulsive will or sense appetite, or from contempt for a directive. Impetuosity is a defect of memory, docility, and reasoning.

Thoughtlessness is a defect of practical judgment and amounts to a defect of circumspection and caution.

Inconstancy is contrary to command, the principal act of prudence, and is a failure to complete a morally good act by refusing to command that an act be done, a refusal rooted in inordinate love of pleasure.

Negligence is also contrary to command, but it differs in that it is a defect on the part of the intellect to direct the will in carrying out some good action. These vices involve a defect in understanding, foresight, and shrewdness.

Prudence and Ethics

As we said above, prudence is both a moral virtue and an intellectual virtue simultaneously, for a moral virtue renders its possessor morally good. A prudent person is one who makes good decisions. A bright and learned person who makes foolish decisions, who is arrogant and subject to outbursts of anger, for example, is hardly someone whom we would hold up as an example of prudence. A person may study and grow in knowledge of the science of ethics without a corresponding moral growth, that is, while holding on to some very serious vices.

Thus, prudence is not quite the same thing as being a moral philosopher or theologian. One may be very learned in these disciplines, but lack prudence, at least to a certain degree. Perhaps we can compare this situation to the person who has studied art history and who knows about proper technique, materials, how this or that artist paints, by whom he was influenced, etc., but who is himself a poor artist. A moral thinker might have good counsel and judgment with regard to general moral issues. He may be a good problem solver and know how to apply universal moral principles to more or less general situations. But, as Aquinas writes: "In wicked men there may be right judgment of a universal principle, but their judgment is always corrupt in the particular matter of action" (S.T. II-II, Q 51, 3, ad 2).

For prudence requires more than an understanding of first principles and precepts. It requires true to being memory, docility, circumspection, discursive reasoning, foresight, and caution as well as a shrewd mind. An expert in moral science might lack the humility to be docile, or lack experience with certain people and the intensity of charity necessary to develop a shrewd mind. His arrogance may render him relatively blind or dark of mind, for the "Lord looks upon the arrogant from afar" (Ps. 138, 6). He may lack patience, and he may have an exaggerated sense of self-importance and a hint of narcissism typical of professors today, and he may carry a great deal of resentment. Such a lack of humility destroys virtue, and without right appetite one is not prudent, for prudence requires a just will, a patient disposition rooted in charity, a humble self-estimation, a spirit of forgiveness, honesty with oneself, self-awareness, an awareness of temptation, etc. Without these, one will lack good counsel and good judgment, at least with regard to highly contingent matters.

For there is a realm that exceeds the range of the science of morality[1], just as there is a large realm that exceeds the limited range of a wireless router. Moral science helps to sharpen judgment, for not all moral matters in the here and now are strictly speaking prudential judgments, such as abortion, active euthanasia, contraception, adultery, lying, etc. The reason is that there are no circumstances that change the nature of these actions, which involve in themselves a deficient willing, that is, willing that is incompatible with complete openness to all human goods, such as human life and marriage, and justice. But a special virtue is required for the here and now precisely because of this limited range; for as we move outside of the realm of the universal and into this rather murky territory of the variable and particular, decisions on what to do and how to proceed become more difficult, far less certain, and they require very well developed sensibilities, intuition, experience, rightly ordered appetite, both rational and sensitive, especially a will formed by charity. It is not always easy to demonstrate the correctness of good prudential judgments; for some people don't see, for their reasoning is grounded in what they know, which in turn is rooted in who they are; for as a person is, so does he see (EN 3, 4. 1113a25-1113b).

A prudent person, on the other hand, is a good person. He has practical intelligence, or practical wisdom, and although one may have speculative wisdom without being morally good, including the science of ethics that settles for general statements about what is variable, one cannot have practical wisdom without being morally good. The more noble a person is, the more wise will he be in the practical sense, that is, in the concrete decisions he is required to make daily in the here and now. As one grows in holiness, that is, in charity and faith, one grows in clear-sightedness that is the offspring of purity of heart. One begins to contemplate God here in this world, for one comes to know God connaturally. One contemplates the genius of his providence and the depths of His love, which the pure of heart know from within. St. Thomas writes: "Now this sympathy or connaturality for Divine things is the result of charity, which unites us to God, according to 1 Cor. 6:17: "He who is joined to the Lord, is one spirit." Consequently wisdom which is a gift, has its cause in the will, which cause is charity, but it has its essence in the intellect, whose act is to judge aright, as stated above" (S.T. II-II, 45, 2). That is why the saint enjoys a level of contemplation and wisdom that is unavailable to the theologian or philosopher who is lacking in charity. The light of contemplation in turn enhances one's ability to determine the mean of reason in fortitude and temperance and all their parts as well as the mean of justice, and the fire of charity renders one more just, brave, and temperate, which in turn spawns a greater prudence. Perhaps moral and emotional growth can be compared to the perpetual motion machine that has yet to be invented.


1. "...speculative reason differs from practical reason as the unchanging differs from the changing. What we know through speculative reason is something which always is what it is; it is invariable and therefore cannot be otherwise than what it is. In this way we know, for example, that a triangle cannot be otherwise than having its angles equal to two right angles. What we know through practical reason is variable, for in seeking to know how to act we are dealing with what is in itself changeable and subject to alteration. But, to avoid a possible misunderstanding here, let us note that what is variable can be known in two ways: in general and in particular.

General statements about what is variable are themselves unchanging. For example, the statement that every twenty-four hours the earth turns completely on its axis is a general statement about something changing. Such knowledge is still speculative even though it is concerned about something changing....The good state of speculative reason is simply knowing truth...The good state of practical reason does not consist simply in knowing truth. Because practical reason is connected with singular action involving desire on the part of both the will and emotion, the virtue of practical reason, though an intellectual virtue itself, will be necessarily connected with moral virtue." John A. Oesterle. Ethics. (New Jersey: Prentice-Hall, Inc 1957. 173-174.

1, 2,