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Nicomachean Ethics | Book 5 | Summary



Section 1

This section analyzes justice and injustice. Justice is a state, and people in this state want to do just actions. Aristotle defines justice as "the lawful and the fair." Injustice includes whatever is "lawless ... and unfair." The unjust person, who is "an overreacher," wishes for the wrong kinds of goods. They desire only the goods "involved in good and bad fortune," or goods needing "qualification" or additional qualities, not the universal goods of the truth.

One important application of justice is maintaining happiness in a political community by creating laws for the common good. This kind of justice involves virtue in relation to other people. Justice is "the complete exercise of complete virtue," since how a man acts toward other people is the true test of his virtue.

Section 2

Aristotle discusses which actions arise solely from injustice and not from other vices. He calls these actions "special injustice." They are characterized by the sole aim of "the pleasure that results from making a profit." Special injustice is concerned specifically with communities and political systems since members can have equal or unequal shares of wealth. Another species of injustice involves transactions—both voluntary transactions like selling and buying, and involuntary transactions like theft, deception, and imprisonment.

Section 3

Distributive justice relates to equality of distribution. Should two people receive equal shares of goods? This depends on whether the two people are equal or not. If they are not, they should each receive a "proportionate" amount according to their worth. Justice, in this case, is proportion.

Section 4

Rectificatory justice, or justice involving transactions, aims to make situations right by restoring them to a state of equality. A judge arbitrating a dispute between two people, for instance, will consider the harm and suffering inflicted on the victim and the profit earned by the offender. The verdict will make their fortunes equal. In this case, justice is "the intermediate between ... loss and profit." Just as in a voluntary financial exchange, each party gets an equal share.

Section 5

Reciprocity, or mutual exchange, is a form of justice involving the economic exchange in communities. Aristotle compares reciprocity to the "eye for an eye" or principle of retaliation in law, often used to make offenders compensate victims fairly for damages. He quotes the mythological judge Rhadamanthus, who described justice as an offender "[suffering] what he did." Nevertheless, true reciprocity, Aristotle says, should consider the context of the offense and the status of the offender, as well as whether the action was voluntary.

He then describes how reciprocity works in the daily commerce or business dealings of a city. The city relies on people receiving and returning good deeds mutually in a state of "proportionate reciprocity." Artisans who offer different skills can exchange their skills for the services they need. Currency or money provides a way to make skills "comparable." Need holds the community together.

A just person will award himself and others "what is proportionately equal" without favoring himself. Injustice, like character vices, concerns "excess and deficiency." An unjust person will give himself more of the "beneficial" than he needs, and avoid the "harmful" more than he should. He acts this way when awarding goods or resources to himself, and when dividing goods or resources between himself and others. Anyone who receives "too little good" as a result has suffered injustice at the hands of the unjust person.

Section 6

Political justice involves the law governing free and equal people. The judicial process "distinguishes the just from the unjust." It is possible to do injustice, or commit an unjust act, without being completely unjust. A just community needs a just ruler who will not be corrupted by power. The payment and honor of their position will be the only rewards they need. Aristotle adds that justice in families is slightly different, since a child is "a part of oneself" for a parent.

Section 7

Political justice has two parts, natural justice and legal justice. Natural justice is "unchangeable and equally valid everywhere," while legal justice is valid wherever people have written down laws. Justice goes beyond the legal—certain human enactments of justice can be used as "measures," but natural justice is universal. Acts of justice and injustice are different from the just and unjust themselves.

Section 8

Aristotle goes on to explain the distinction between a state of justice and individual actions. Someone can do just or unjust actions without meaning to. However, they do justice or injustice only if their actions are willing and voluntary. A just action done in ignorance or under coercion—for instance, making a payment out of fear—is not justice. Likewise, an unjust action done in ignorance, perhaps striking someone you did not mean to strike, is error or misfortune. An action taken in anger, without deliberation, may be an unjust action, but it does not make a person unjust. A person is unjust only if they have deliberated and decided to do harm.

To further explain the difference between an unjust action and an unjust person, Aristotle distinguishes between "actions caused by spirit" or emotional impulse and actions resulting from a decision. An unjust person's actions are caused by their principles or fundamental beliefs. An angry, passionate action may be caused by another person's provocation, not by the agent or actor's internal principles. However, a more deliberate action, like premeditated cheating, proves an unjust character. The cheater's decision causes the injustice.

Section 9

Is it possible for someone to endure injustice willingly, or receive justice unwillingly? Aristotle discusses "puzzles," circumstances that do not fit into exact logic. Then he refines his definition of injustice, redefining it as "harming with knowledge of the victim, the instrument, and the way." Someone can harm himself willingly if he is incontinent (weak-willed), for instance. Aristotle adds "against the wish of the victim" to his refined definition of injustice. He decides no one suffers injustice willingly. However, what if someone gets more than he deserves? The recipient does not do injustice—the distributor does, since he is the one who gave out the resources unequally. Nevertheless, the recipient does "something that is unjust."

It is easy to understand the law, but it is not easy to achieve the state of being just. The truly just person has to learn "how actions must be done, and how distributions must be made." Acts of injustice also rely on the person's "being in a certain state."

Section 10

Decency is related to justice, although their connection might not be obvious. There are situations in which "no universal rule can be correct," not even the law. Some areas of life cannot be legislated at all. A legislator can apply decency through "rectification of law," or adapting the law to fit the demands of the situation, like architects adapt building to the shape of a stone. A decent person might also take less than he is owed, even if the law favors him.

Section 11

Aristotle explores whether a person can inflict an injustice upon oneself, or not. Aristotle returns to the idea that it is impossible to suffer injustice willingly, to support his belief that no one can do injustice to oneself. Justice and injustice "always involve more than one person." A suicide, for instance, is considered an injustice to the city. Aristotle admits a person's rational and nonrational soul can be in conflict, and they can "suffer something against [their] own desires," but this is not equivalent to an act of injustice against the self.


Aristotle transitions from discussing individual behavior in a community to guidelines for the community as a whole. Justice and injustice are broad terms, and there are many ways to talk about the two contrary states. Just as the two states can take multiple forms (justice, for instance, can be general justice or special justice), just and unjust actions can show up in multiple guises. His working definition for justice is "the lawful and what is fair," but how can political communities apply both lawfulness and fairness? Again, Aristotle wants to provide helpful outlines, not specific directions. He wants to give readers the tools to behave well in their own lives.

By homonymy Aristotle means words that appear self-evident but that have problematic definitions. For example, because the terms justice and injustice are so imprecise, he spends this book analyzing common problems and the type of justice needed to resolve each problem.

In Section 1, he connects justice and the law. Since laws aim for "the common benefit" and encourage virtues by their nature—legal behavior is likely to be good behavior—laws are a communal application of justice. Moreover, justice itself is a way for people to improve others' lives through interpersonal relations, or "virtue [as] related to another." While temperance can make an individual's life healthier, and friendliness and wit make someone good company, justice has the power to do someone else lasting good. It requires no material wealth, simply a sense of proportion and a desire to do right. Moreover, it is much harder than individual virtue to achieve.

Section 2 says that even following the law does not always mean doing just actions or being just. Although just and law-abiding behaviors are likely to coincide, it is always possible, especially in a corrupt political system, for laws to be unjust or immoral. This is why Aristotle qualifies that good people are not by definition "every sort of good citizen." Sometimes being a good person means pursuing justice, perhaps even in defiance of the law, a concept that Martin Luther King Jr. relied upon in Letter from Birmingham Jail.

When he considers injustice and "overreaching," Aristotle assumes essential resources, like money and food, will always be in limited supply. To overreach is to take more than one's share and cheat the community, which consists of other individuals. Rich people who use their wealth for the common good do not overreach, but rich people who hoard their resources do. Avoidance of harm at someone else's expense, like avoiding military service because you know others will volunteer in your place, is another way of overreaching. An overreacher knows someone else will be directly harmed.

Special justice and special injustice deal with dividing resources in a community. Aristotle views special injustice as the specific desire for profit, and for more profit than a person deserves. Special justice aims for fair allocation of resources. The two types of special justice Aristotle analyzes, distributive and rectificatory justice, are still widely studied in law, philosophy, and political science.

Justice is part of any discourse on morality. In the Nicomachean Ethics, Aristotle defines equality as a major aspect of justice: equals should be treated equally. Similarly, people who are not equal should not be treated equally. He realizes equals is a tricky term when dealing with social status. Are all free citizens equal? If goods are distributed according to worth, how is worth measured? Who deserves honor? Who deserves profit? Should people receive goods according to their need or their effort? Who should be in charge? Aristotle knows he will not come up with exact answers to these questions, but he can give principles that will lead to just outcomes if followed correctly.

Distributive justice has broad applications in the Ethics. Its aim is for everyone to get proportionate, if not numerically equal, shares of a good or service. No one should benefit too much, and no one should be too burdened. Nevertheless, proportion is essential. Someone who works more should be paid more. Someone who makes a greater contribution to society should be honored more. Aristotle's mathematical explanation of proportion uses numerical variables to show how distribution of goods can be impartial and fair.

Rectificatory justice concerns how to handle a situation where distributive justice has already gone wrong. Rectify means to make right. This type of justice restores an unfair situation to a fair one. It can be used in monetary transactions, which most people think of when they hear the terms loss and profit. However, it also applies to crimes like assault or murder. The victim has lost something, and the attacker, Aristotle acknowledges, has profited in a way, if only by causing someone else to suffer. Even in cases where no one can identify a clear sum of profit and loss, rectification is still essential. An attacker, for example, may be required to give money to a victim's family.

Again, Aristotle uses mathematical principles to clarify his position, referring to a judge as a bisector who adds and subtracts and a mediator who finds the mean. His illustrations with numerical variables show both a zero-sum approach, where the victim gains what the offender loses ("an equal share"), and an approach where the victim receives only the "intermediate" amount.

Aristotle focuses on economic transactions when he describes reciprocity or "justice in exchange." He feels reciprocity does not apply to crimes, when judges need to consider the context—he gives the example of a "ruling official" who, in the process of performing his duties, wounds a citizen. Financial exchanges are more straightforward. They are based on need. Unlike later economic thinkers, Aristotle does not identify need with demand, nor does he equate need with skill. Nevertheless, he explains the requirements of a functional and thriving community. If members in the community have diverse skills and talents, then everyone's needs will be met. Reciprocity makes sure that every professional, whatever their product, charges fairly and is fairly compensated for their services.

Who is in charge? Aristotle does not trust a human ruler with unchecked power not to become a tyrant. He prefers "reason" itself to rule, since reason is impartial. In Book 8, when Aristotle describes different political systems, he says kingship is ideal. Earlier, he defined a good king as the human embodiment of reason, prepared to "labor for another's benefit" and keep the common good in mind. Moreover, any king who follows a virtuous concept of justice will use his own morals to keep his power benevolent.

Even good kingship does not control the behavior of human subjects. As Aristotle compares natural and legal justice, he examines laws people follow for no particular reason other than convention or tradition, such as making sacrifices to Brasidas, a dead Spartan general. People confuse these laws with "natural justice," a truly just system applicable to any community.

In Section 8 Aristotle begins to show how an individual can be responsible for justice or injustice in his city. Crimes of passion he describes as "voluntary" actions, although he qualifies that these were acted on "without previous deliberation." He then defines the types of ignorance with which a person may inflict harm and when the action qualifies as a "misfortune." In other words, he holds people to a very high standard for their behavior in the community, although he allows for errors of both judgment and circumstance.

Aristotle's arguments in Section 9 reveal that justice even affects one's relationship to oneself. If an incontinent person indulges to the point of physical harm, he or she has willingly suffered an unjust act. Moreover, a person who gives someone else more than is deserved, in what was meant to be an equal exchange, does injustice even though the other does not profit.

There is still a critical difference between doing something unjust and being unjust. An unplanned crime resulting from spirited anger, or an accidental breaking of a promise, is a voluntary unjust action but does not reveal an unjust character. A premeditated crime, the result of a decision, means the criminal is unjust to the core. People who commit unjust actions can change their state of character. The unjust person cannot.

The infinite varieties of human experience make it impossible for every situation to be covered by the law. These gray areas are where Aristotle sees the need for decency. Even if decent actions conflict with legal actions, the decent person will naturally be just. Aristotle calls decency "rectification of law" or knowing the right thing to do when the law is inadequate. He finds decency rarer than and even superior to justice. Many people can follow rules, but only a few people can find right action when it transcends the rule of law. Decency involves a certain practical knowledge and compassion, similar to prudence, which he will describe in the next section.

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