Key Ideas
1. Every deliberate activity aims at some good
Human purposes form an ordered structure in which some ends are chosen for the sake of more comprehensive ends.
2. Happiness is the highest practical end
Flourishing is desired for itself and gives direction to other choices rather than serving as a means to something further.
3. Happiness is excellent activity
A good life consists in actively exercising rational capacities well across a complete life.
4. Character is formed through habit
Repeated choices train emotions and perceptions until virtues become stable dispositions. In Book II, Chapter I, Aristotle compares acquiring virtue with learning a craft: we develop capacities by exercising them. Repetition alone does not guarantee improvement, however. Practising badly can form a bad disposition, so education and correction matter. The claim is that character develops through the quality of repeated conduct, not that whatever becomes habitual is virtuous.
5. Virtue seeks a mean relative to circumstances
The appropriate response avoids excess and deficiency through practically intelligent judgement, not simple arithmetic. In Book II, Chapters VI–VII, the mean concerns the fitting person, occasion, object and manner of acting or feeling. Courage does not mean accepting a fixed halfway amount of danger: it requires judging which risks are worth facing and why. Aristotle also explicitly denies that every action admits a virtuous mean. His account does not recommend a moderate amount of wrongdoing. This limit matters whenever “everything in moderation” is offered as a summary of his ethics.
6. Ethics cannot have mathematical precision
General principles guide action, but variable situations require perception of particulars.
7. Voluntary action grounds responsibility
Praise and blame depend upon compulsion, ignorance, choice and the degree to which an action belongs to the agent.
8. Deliberation concerns practicable means
People deliberate about what can be done through their agency to realise an end they seek.
9. Moral virtue orders emotion
Excellence involves feeling fear, anger, desire and pleasure appropriately rather than eliminating emotion.
10. Justice concerns fair relations
Distribution, correction and reciprocity require forms of equality suited to different social transactions.
11. Equity corrects the rigidity of general rules
Exceptional cases may require judgement faithful to the law’s purpose rather than its literal wording.
12. Practical wisdom joins good ends with good means
Cleverness becomes virtuous only when it serves a sound conception of living well.
13. Knowledge can fail to govern action
Weakness of will occurs when appetite prevents a person from actively applying better judgement to a particular situation.
14. Friendship has forms based on utility, pleasure and character
The basis of a friendship determines its depth, expectations and stability.
15. Complete friendship values the person for his own sake
Good friends reciprocally wish one another well and share activity over time.
16. Proper self-love supports generosity
A person devoted to noble action can give up external advantages while preserving what is best in character.
17. Pleasure completes successful activity
Pleasures differ with the activities they accompany and receive their quality from those activities.
18. Contemplation is presented as the highest activity
The exercise of intellect is valued for continuity, self-sufficiency and its orientation towards truth.
19. External goods still matter
Virtue is central but embodied human activity requires some health, resources, relationships and favourable conditions.
20. Ethics depends upon politics and education
Laws and institutions shape habits, making communal organisation part of the project of human flourishing.
Test your understanding against the text
Practice and character: Book II, Chapter I
Imagine two people who repeatedly give money. One tries to help where help is needed; the other mainly seeks admiration. Identify what the observable actions share, then ask which features a judgement of character must examine. Repetition is evidence of a pattern, but it does not by itself explain its purpose or quality. Return to the passage about learning a craft and explain why practising well matters to Aristotle’s argument.
Courage and the mean: Book II, Chapters VI–VII
Consider a person who faces a risk to help someone and a person who accepts the same risk to show off. Would facing equal danger make them equally courageous? Write down the circumstances and reasons you would need before answering. Then explain why locating virtue between excess and deficiency cannot be reduced to counting how often someone takes risks.
Assess a limitation
Aristotle gives early education a major role in the formation of character. Ask how someone whose upbringing reinforced poor habits could begin to change them. Distinguish what the argument establishes—that conduct shapes dispositions—from the further question of how difficult reform may be. An objection should identify a missing explanation or an implausible assumption, rather than simply observing that becoming virtuous takes effort.
Use the companion resources
These numbered ideas are revision notes. The Summary traces the ten Books, while the Explanation develops the arguments and their connections. Consult Book II in the D. P. Chase translation to check the passages discussed here. Chapter references concern divisions within that Book, not separately numbered pages of the website.