The Nicomachean Ethics

What makes life worth living? Aristotle's Nicomachean Ethics begins with the question of the ultimate end – the highest good that guides every human action. He argues that if every purposeful act aims at some good, there must be one final end that makes all other pursuits meaningful. That end, he concludes, is happiness (eudaimonia) — not a fleeting pleasure but the activity of the soul expressing virtue in accordance with reason.

Aristotle’s ethics is practical and architectural. It begins with ordinary experience — observing that medicine aims at health, shipbuilding at vessels, and politics at civic flourishing — and builds a theory that connects personal virtue, social institutions, and human nature. Happiness, he insists, is an activity, not a state; it unfolds through a whole life lived in excellence and supported by the right external conditions.

The Function Argument: What Defines Human Good

To know what happiness truly is, Aristotle asks what the function of a human is. If a musician’s good lies in making music well, then a human’s good lies in fulfilling the distinctive function of rational activity. The human function, therefore, is the life of the soul according to reason, and the good life is this activity done well — that is, in accordance with virtue. Virtue (aretê) defines the excellence by which humanity achieves its proper work.

Virtue, Politics, and Self-Sufficiency

Because humans live in communities, politics becomes the master science of the good. A city that cultivates virtuous citizens sustains the highest human end. Lawmakers, educators, and moral teachers are central: they shape character and train individuals toward the mean. Happiness must be complete and self-sufficient, yet Aristotle admits that virtue alone is not enough if deprived of external goods such as friends, family, and a stable political order. Flourishing needs support from fortune and society — though virtue remains its primary foundation.

Activity and Fortune

Aristotle acknowledges that chance can influence happiness (as with the tragic fate of Priam), but insists that true happiness rests on inner excellence more than external events. Solon’s warning to “call no man happy until he dies” captures Aristotle’s realism: happiness is measured over a whole life, not by transient prosperity. Ultimately, you are asked to integrate moral, intellectual, and civic virtue into an enduring way of life — one where reason governs action, desires are trained by habit, and contemplation completes the human purpose.

Aristotle insists that moral virtue does not arise by nature but through habituation. You become just by doing just acts, temperate by practicing temperance. Virtue is a trained faculty — a settled disposition formed by repeated behavior under guidance. This fundamental idea turns ethics from theory into a practical program of character formation.

Two Kinds of Excellence

There are two species of virtue: intellectual and moral. Intellectual virtues — wisdom, understanding, and prudence — grow through teaching and time. Moral virtues — courage, temperance, justice — arise from habituation. Lawgivers therefore matter profoundly: they use praise, punishment, and education to create habits aligned with noble pleasure and rational control.

The Structure of the Soul

Aristotle divides the soul into rational and nonrational parts. The irrational includes the appetitive faculty, which can listen to reason. Moral virtue belongs to this part: it harmonizes desire and emotion with rational judgment. When the appetites obey reason naturally and with joy, you are truly virtuous; when they resist, you remain undeveloped.

Habituation and Law

Virtue must therefore be practiced, not merely studied. Moral education must begin early, aligning pleasure and pain with virtue. The well-ordered state functions as a school of character, forming citizens as Cretan and Spartan laws tried to do. For Aristotle, ethics is civic craftsmanship: a society is just insofar as it trains its people to enjoy what is noble and resist what is base.

Virtue, Aristotle teaches, is not extreme but balanced. Moral excellence finds its place in the mean between excess and deficiency — a principle that defines his practical method of judgment. You achieve virtue by perceiving the right measure, not by calculating it mathematically but by developing sensitivity through experience.

Finding the Right Measure

Every emotion or action can err by excess or defect: in fearing, acting, enjoying, spending. Courage strikes the mean between cowardice and rashness; temperance lies between insensibility and indulgence. The correct mean depends on you—the individual, your situation, and roles. As Aristotle’s analogy of the archer suggests, hitting the target requires trained perception, not formulaic calculation.

Examples in Action

Courage manifests principally in battle, where death can be noble. The coward feels too much fear; the fool feels too little. Temperance concerns bodily pleasures of touch and taste—the appetites shared with animals. Liberality and magnificence moderate giving and spending according to proportion. Justice, likewise, finds its mean in equitable distribution.

Why the Mean Matters

The mean expresses practical wisdom: virtue is about aiming correctly at the good. It rejects rule-based morality and teaches moral perception. You learn by doing and feeling correctly—training yourself to desire the right things for the right reasons, until harmony between reason and passion becomes natural.

For Aristotle, pleasure and pain are moral barometers. They reveal what kind of person you are. The virtuous find the right things pleasant—noble acts, temperate restraint—while the vicious find corrupt pleasures alluring. Pleasure and pain are thus the emotional tests of character formation.

Training Desire

In early education, children must be trained to enjoy what is good and dislike what is shameful. This emotional alignment becomes the foundation for all virtue. If abstaining from excess delights you, you are temperate; if it pains you, you remain profligate. Law and custom embed this principle through habit, praise, and punishment.

Different Pleasures, Different Morals

Aristotle distinguishes bodily pleasures from those of intellect or honor. The former are fleeting and often corrupt; the latter perfect noble faculties. He also notes asymmetry: profligacy, being chosen, is more voluntary than cowardice, driven by pain and fear. This insight anchors responsibility and reform—pleasure can be retrained, but fear may limit choice.

Testing Character

When you endure pain for a noble end—the courageous soldier’s wounds or the philosopher’s intense effort—you exhibit the firmness of virtue. Moral progress means developing loves and hates that mirror rational order, until what is pleasing and painful coincides with what is right and wrong.

Moral responsibility depends on voluntary choice. Aristotle distinguishes acts compelled by force or ignorance from those chosen freely. Praise and blame apply only where the will is active and knowledge present.

Voluntary and Involuntary

Acts done under compulsion or ignorance of particulars are involuntary—like being carried away by a storm or harming someone unknowingly. Mixed acts, like jettisoning cargo in a tempest, are voluntary in themselves but excusable in context. Law and ethics must weigh intention and circumstance together.

From Wish to Choice

You wish for ends, but choose means. Choice (prohairesis) is desire regulated by deliberation. You deliberate only about what lies within your power—the physician considers how to heal, not whether healing is good. Deliberation links reason to action, transforming abstract aim into concrete deed.

Law, Punishment, and Formation

Because vice results from chosen habits, law punishes negligence, including voluntary drunkenness or ignorance caused by carelessness. Virtue, too, is voluntary, since you can train yourself to deliberate correctly. In Aristotle’s eyes, freedom is not mere spontaneity—it is disciplined choice guided by reason.

Justice, for Aristotle, is both moral and mathematical. It is complete virtue expressed toward others and also a principle of proportion in social and economic life. You encounter justice everywhere: in fair distributions, rectifications, prices, and laws.

Distributive and Corrective Justice

Distributive justice divides common resources—honors, wealth—according to merit. It is geometric, proportional to deserts. Corrective justice restores equality in private transactions. It is arithmetic: if one gains unjustly, a judge subtracts the excess and restores balance. In both, justice acts as equilibrium.

Equity and Law

Since general laws cannot foresee every case, equity corrects their rigidity. The equitable judge interprets law as the legislator would if present. Moral virtue thus merges with institutional reason—the humane adjustment of universal rules to individual situations.

Justice and the Polis

Justice binds private goodness to public order. When suicide or crime occurs, Aristotle treats it as injury to the polis, not just oneself. Moral and civic justice are inseparable: your virtue contributes to the communal balance that sustains human flourishing.

To act virtuously, you need practical wisdom (phronesis), the intellectual virtue that guides right action. Aristotle separates the rational soul’s faculties—scientific and deliberative—and maps five intellectual excellences: art, science, prudence, wisdom, and intuitive reason.

Prudence and Moral Action

Prudence is an active habit that reasons well about what is good and achievable. It differs from cleverness, which may calculate means toward any end, even base ones. True prudence requires moral virtue because only rightly ordered desires enable right ends. Pericles exemplifies prudence; Anaxagoras and Thales display speculative wisdom but lack civic intelligence.

Wisdom and Nous

Wisdom unites scientific knowledge and intuitive reason concerning the highest truths—cosmic and divine. Nous underlies both: it grasps first principles directly. In ethics, you depend on nous to perceive particular facts correctly—the real situations on which prudence deliberates.

Mind and Character United

No one is fully virtuous without prudence, and no one is prudent without moral virtue. Reason and desire must harmonize. Ethical failure often occurs when intellect is separated from emotion—when knowledge lacks trained appetite. Aristotle thus bridges thought and choice: moral wisdom is intellect embodied in habit.

Why do people act against what they know is right? Aristotle dissects moral failure through distinctions between continence, incontinence, and vice. He moves beyond Socrates’ view that all wrongdoing is ignorance and shows how passion can defeat active knowledge.

Knowing but Not Acting

An incontinent person knows the good but fails at the moment of action. The practical syllogism collapses: appetite replaces the rational minor premise. This resembles a drunkard reciting principles without awareness of their meaning. Remorse shows that knowledge persists but is overpowered.

Vice and Profligacy

A profligate deliberately chooses bad ends and lacks regret; he is hardened in character. Incontinent people can reform; vicious persons rarely can. Aristotle compares moral weakness to temporary illness and vice to chronic disease. Education and habituation aim to prevent weakness from calcifying into vice.

Reforming Desire

Law and upbringing intervene precisely here: transforming emotional structure so rational judgment remains vivid during action. This moral psychology reinforces Aristotle’s practical conviction—virtue must be trained, not merely taught.

Aristotle elevates friendship (philia) to a central ethical and political role. You cannot live well or even survive without friends. Friendship binds individuals to the community and mirrors virtue itself—loving others as you wish the good for yourself.

Three Kinds of Friendship

There are friendships of utility, pleasure, and virtue. Utility serves practical ends; pleasure serves enjoyment; virtue joins souls who love goodness for its own sake. The last is rare and enduring because virtue itself is stable. Such friends love each other as second selves.

Friendship and Justice

The more intimate the relationship, the more justice and equity it demands. Unequal friendships—parent/child, ruler/subject—require proportional affection. Political friendship anchors civic concord: shared virtue and goodwill stabilize the polis the way justice balances individuals.

Moral Education through Love

True friendship also becomes moral training: good friends help each other correct faults and pursue noble pleasures. They exemplify Aristotle’s vision of ethical community—the private mirror of the public good.

All roads in the Nicomachean Ethics lead to one summit: the contemplative life. After exploring moral virtue, friendship, justice, and pleasure, Aristotle concludes that contemplation is humanity’s highest activity—the fullest expression of reason and the closest likeness to divine life.

Why Thought Outranks Action

Contemplation is self-sufficient, continuous, and pursued for its own sake. Political action depends on external conditions and fluctuates with fortune; contemplation perfects the noblest part of the soul and provides intrinsic joy. The gods themselves, Aristotle imagines, live this way—thinking eternally, not acting politically.

External Goods and Human Limits

Still, Aristotle remains practical: the contemplative life requires health, leisure, and modest resources. You do not need luxury, but you cannot contemplate without peace and freedom. Solon and Anaxagoras illustrate how wisdom surpasses wealth and power as measures of happiness.

Education, Law, and Realization

To make contemplation possible, states must educate citizens in virtue from childhood. Habituation, not argument alone, reforms passion. Law becomes moral architecture, guiding people toward intellectual leisure. Ultimately, to live well means to join ethical action and contemplative understanding, realizing within your mortal life the pattern of divine reason itself.