Online Guide to Ethics and Moral Philosophy

Robert Cavalier

Philosophy Department
Carnegie Mellon

Part I History of Ethics

Preface: The Life of Socrates
Section 1: Greek Moral Philosophy
Section 2: Hellenistic and Roman Ethics
Section 3: Early Christian Ethics
Section 4: Modern Moral Philosophy
Section 5: 20th Century Analytic Moral Philosophy

Part II Concepts and Problems

Preface: Meta-ethics, Normative Ethics and Applied Ethics
Section 1: Ethical Relativism
Section 2: Ethical Egoism
Section 3: Utilitarian Theories
Section 4: Deontological Theories
Section 5: Virtue Ethics
Section 6: Liberal Rights and Communitarian Theories
Section 7: Ethics of Care
Section 8: Case-based Moral Reasoning
Section 9: Moral Pluralism

Part III Applied Ethics

Preface: The Field of Applied Ethics
Section 1: The Topic of Euthanasia
Multimedia Module: A Right to Die? The Dax Cowart Case
Section 2: The Topic of Abortion
Multimedia Module: The Issue of Abortion in America
Postscript: Conflict Resolution

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Excerpts from Terence Irwin's entry on Aristotle in the Routledge Encyclopedia of Philosophy (General Ed. Edward Craig)

Aristotle (384-322 BCE)

Aristotle of Stagira is one of the two most important philosophers of the ancient world, and one of the four or five most important of any time or place. He was not an Athenian, but he spent most of his life as a student and teacher of philosophy in Athens. For twenty years he was a member of Plato's Academy; later he set up his own philosophical school, the Lyceum. During his lifetime he published philosophical dialogues, of which only fragments now survive. The 'Aristotelian corpus' (1462 pages of Greek text, including some spurious works) is probably derived from the lectures that he gave in the Lyceum.

Aristotle is the founder not only of philosophy as a discipline with distinct areas or branches, but, still more generally, of the conception of intellectual inquiry as falling into distinct disciplines. He insists, for instance, that the standards of proof and evidence for deductive logic and mathematics should not be applied to the study of nature, and that neither of these disciplines should be taken as a proper model for moral and political inquiry. He distinguishes philosophical reflection on a discipline from the practice of the discipline itself. The corpus contains contributions to many different disciplines, not only to philosophy.

Some areas of inquiry in which Aristotle makes a fundamental contribution are these:

(1) Logic. Aristotle's Prior Analytics constitutes the first attempt to formulate a system of deductive formal logic, based on the theory of the 'syllogism'. The Posterior Analytics uses this system to formulate an account of rigorous scientific knowledge. 'Logic', as Aristotle conceives it, also includes the study of language, meaning and their relation to non-linguistic reality; hence it includes many topics that might now be assigned to philosophy of language or philosophical logic (Categories, De Interpretatione, Topics).

(2) The study of nature. About a quarter of the corpus (see especially the History of Animals, Parts of Animals, and Generation of Animals; also Movement of Animals, Progression of Animals) consists of works concerned with biology. Some of these contain collections of detailed observations. (The Meteorology contains a similar collection on inanimate nature.) Others try to explain these observations in the light of the explanatory scheme that Aristotle defends in his more theoretical reflections on the study of nature. These reflections (especially in the Physics and in Generation and Corruption) develop an account of nature, form, matter, cause and change that expresses Aristotle's views about the understanding and explanation of natural organisms and their behaviour. Natural philosophy and cosmology are combined in On the Heavens.

(3) Metaphysics. In his reflections on the foundations and presuppositions of other disciplines, Aristotle describes a universal 'science of being qua being', the concern of the Metaphysics. Part of this universal science examines the foundations of inquiry into nature. Aristotle formulates his doctrine of substance, which he explains through the connected contrasts between form and matter, and between potentiality and actuality. One of his aims is to describe the distinctive and irreducible character of living organisms. Another aim of the universal science is to use his examination of substance to give an account of divine substance, the ultimate principle of the cosmic order.

(4) Philosophy of mind. The doctrine of form and matter is used to explain the relation of soul and body, and the different types of soul found in different types of living creatures. In Aristotle's view, the soul is the form of a living body. He examines the different aspects of this form in plants, non-rational animals and human beings, by describing nutrition, perception, thought and desire. His discussion (in On the Soul, and also in the Parva Naturalia) ranges over topics in philosophy of mind, psychology, physiology, epistemology and theory of action.

(5) Ethics and politics (Nicomachean Ethics, Eudemian Ethics, Magna Moralia). In Aristotle's view, the understanding of the natural and essential aims of human agents is the right basis for a grasp of principles guiding moral and political practice. These principles are expressed in his account of human wellbeing, and of the different virtues that constitute a good person and promote wellbeing. The description of a society that embodies these virtues in individual and social life is a task for the Politics, which also examines the virtues and vices of actual states and societies, measuring them against the principles derived from ethical theory.

(6) Literary criticism and rhetorical theory (Poetics, Rhetoric). These works are closely connected both to Aristotle's logic and to his ethical and political theory.



Aristotle was born in 384 BC, in the Macedonian city of Stagira, now part of northern Greece. In his lifetime the kingdom of Macedon, first under Philip and then under Philip's son Alexander ('the Great'), conquered both the Greek cities of Europe and Asia and the Persian Empire. Although Aristotle spent much of his adult life in Athens, he was not an Athenian citizen. He was closely linked to the kings of Macedon, whom many Greeks regarded as foreign invaders; hence, he was affected by the volatile relations between Macedon and the Greek cities, especially Athens.

Aristotle was the son of Nicomachus, a doctor attached to the Macedonian court. In 367 BC Aristotle came to Athens. He belonged to Plato's Academy until the death of Plato in 347; during these years Plato wrote his important later dialogues (including the Sophist, Timaeus, Philebus, Statesman, and Laws), which reconsider many of the doctrines of his earlier dialogues and pursue new lines of thought. Since there was no dogmatic system of 'Platonism', Aristotle was neither a disciple of such a system nor a rebel against it. The exploratory and critical outlook of the Academy probably encouraged Aristotle's own philosophical growth.

In 347 BC Aristotle left Athens, for Assos in Asia Minor. Later he moved to Lesbos, in the eastern Aegean, and then to Macedon, where he was a tutor of Alexander. In 334 he returned to Athens and founded his own school, the Lyceum. In 323 Alexander died; in the resulting outbreak of anti-Macedonian feeling in Athens Aristotle left for Chalcis, on the island of Euboea, where he died in 322.

Aristotle married Pythias, a niece of Hermeias, the ruler of Assos. They had a daughter, also called Pythias. After the death of his wife, Aristotle formed an attachment to Herpyllis, and they had a son Nicomachus.


The human good

Aristotle's account of rational agents, choice, deliberation and action is an appropriate starting point for his ethical theory. Ethics is concerned with the praiseworthy and blameworthy actions and states of character of rational agents; that is why it concerns virtues (praiseworthy states) and vices (blameworthy states) (see Arete).

Aristotle's ethical theory is mostly contained in three treatises: the Magna Moralia, the Eudemian Ethics and the Nicomachean Ethics. The titles of the last two works may reflect a tradition that Eudemus (a member of the Lyceum) and Nicomachus (the son of Aristotle and Herpyllis) edited Aristotle's lectures. The Magna Moralia is widely agreed not to have been written by Aristotle; some believe, with good reason, that it contains a student's notes on an early course of lectures by Aristotle. The Eudemian Ethics is now widely agreed to be authentic, and generally (not universally) and reasonably taken to be earlier than the Nicomachean Ethics. Three books (Nicomachean Ethics V-VII = Eudemian Ethics IV-VI) are assigned by the manuscripts to both the Eudemian Ethics and the Nicomachean Ethics.

Aristotle conceives 'ethics' (Magna Moralia 1181a24) as a part of political science; he treats the Nicomachean Ethics and the Politics as parts of a single inquiry (Nicomachean Ethics X 9). Ethics seeks to discover the good for an individual and a community (Nicomachean Ethics I 2), and so it begins with an examination of happiness, (eudaimonia). ('Wellbeing' and 'welfare' are alternative renderings of eudaimonia that may avoid some of the misleading associations carried by 'happiness'; see Eudaimonia.) Happiness is the right starting point for an ethical theory because, in Aristotle's view, rational agents necessarily choose and deliberate with a view to their ultimate good, which is happiness; it is the end that we want for its own sake, and for the sake of which we want other things (so that it is the ultimate non-instrumental good). If it is to be an ultimate end, happiness must be complete (or 'final'; teleion) and self-sufficient (Nicomachean Ethics I 1-5, 7).

To find a more definite account of the nature of this ultimate and complete end, Aristotle argues from the human function (ergon), the characteristic activity that is essential to a human being in the same way that a purely nutritive life is essential to a plant and a life guided by sense perception and desire is essential to an animal (Nicomachean Ethics I 7). Since a human being is essentially a rational agent, the essential activity of a human being is a life guided by practical reason. The good life for a human being must be good for a being with the essential activity of a human being; hence it must be a good life guided by practical reason, and hence it must be a life in accordance with the virtue (arete) that is needed for achieving one's good. The human good, therefore, is an actualization of the soul in accordance with complete virtue in a complete life. This 'complete virtue' appears to include the various virtues described in the following books of the Nicomachean Ethics; this appearance, however, may be challenged by Nicomachean Ethics.


Virtue of character

From the general conception of happiness Aristotle infers the general features of a virtue of character (0thik0aret0; Nicomachean Ethics I 13). He agrees with Plato in recognizing both rational and non-rational desires. One's soul is in a virtuous condition in so far as the non-rational elements cooperate with reason; in this condition human beings fulfil their function well. The argument from the human function does not make it clear what states of a rational agent count as fulfilling the human function. Aristotle seeks to make this clearer, first through his general account of virtue of character, and then through his sketches of the individual virtues.

A virtue of character must be a 'mean' or 'intermediate' state, since it must achieve the appropriate cooperation between rational and non-rational desires; such a state is intermediate between complete indulgence of non-rational desires and complete suppression of them. (Aristotle is not recommending 'moderation' - for example, a moderate degree of anger or pleasure - in all circumstances.) The demand for cooperation between desires implies that virtue is more than simply control over desires; mere control is 'continence' (enkrateia) rather than genuine virtue.

The task of moral education, therefore, is to harmonize non-rational desires with practical reason. Virtuous people allow reasonable satisfaction to their appetites; they do not suppress all their fears; they do not disregard all their feelings of pride or shame or resentment (Nicomachean Ethics 1126a3-8), or their desire for other people's good opinion. Aristotle's sketches of the different virtues show how different non-rational desires can cooperate with practical reason.


Virtue, practical reason and incontinence

A virtuous person makes a decision (prohairesis) to do the virtuous action for its own sake. The correct decision requires deliberation; the virtue of intellect that ensures good deliberation is prudence (or 'wisdom', phronesis; Nicomachean Ethics VI 4-5); hence the mean in which a virtue lies must be determined by the sort of reason by which the prudentwould determine it (1107a1-2). Virtue of character is, therefore, inseparable from prudence. Each virtue is subject to the direction of prudence because each virtue aims at what is best, as identified by prudence.

In claiming that prudence involves deliberation, Aristotle also emphasizes the importance of its grasping the relevant features of a particular situation; we need to grasp the right particulars if deliberation is to result in a correct decision about what to do here and now. The right moral choice requires experience of particular situations, since general rules cannot be applied mechanically. Aristotle describes the relevant aspect of prudence as a sort of perception or intuitive understanding of the right aspects of particular situations (Nicomachean Ethics VI 8, 11).

These aspects of prudence distinguish the virtuous person from 'continent' and 'incontinent' people (Nicomachean Ethics VII 1-10). Aristotle accepts the reality of incontinent action (akrasia), rejecting Socrates' view that only ignorance of what is better and worse underlies apparent incontinence. He argues that incontinents make the right decision, but act contrary to it. Their failure to stick to their decision is the result of strong non-rational desires, not simply of cognitive error. Still, Aristotle agrees with Socrates in believing that ignorance is an important component of a correct explanation of incontinence, because no one can act contrary to a correct decision fully accepted at the very moment of incontinent action.

The error of incontinents lies in their failure to harmonize the demands of their appetites with the requirements of virtue; their strong appetites cause them to lose part of the reasoning that formed their decision. When they act, they fail to see clearly how their general principles apply to their present situation. If their failure results from an error in deliberation, it is clear why Aristotle insists that incontinent people lack prudence.


Choice, virtue, and pleasure

It is initially puzzling that virtuous people decide to act virtuously for its own sake as a result of deliberation. If they decide on virtuous action for its own sake, then their deliberation causes them to choose it as an end in itself, not simply as a means. Decision and deliberation, however, are not about ends but about 'the things promoting ends' (ta pros ta telos, often rendered 'means to ends'). Aristotle's description of the virtuous person, then, seems to attribute to decision a role that is excluded by his explicit account of decision.

This puzzle is less severe once we recognize that Aristotle regards different sorts of things as 'promoting' an end. Sometimes he means (1) that the action is external and purely instrumental to the end; in this way buying food 'promotes' eating dinner. Sometimes, however, he means (2) that the action is a part or component of the end, or that performing the action partly constitutes the achieving of the end; in this way eating the main course 'promotes' eating dinner. Deliberation about this second sort oof 'promotion' shows that an action is worth choosing for its own sake, in so far as it partly constitutes our end.

This role for deliberation explains how virtuous people can decide, as a result of deliberation, on virtuous action for its own sake; they choose it as a part of happiness, not as a merely instrumental means. Prudence finds the actions that promote happiness in so far as they are parts of the happy life. Such actions are to be chosen for their own sake, as being their own end; they are not simply instrumental means to some further end. The virtuous person's decision results from deliberation about the composition of happiness; virtuous people decide on the actions that, by being non-instrumentally good, are components of happiness in their own right.

Aristotle's demand for the virtuous person to decide on the virtuous action for its own sake is connected with two further claims: (1) the virtuous person must take pleasure in virtuous action as such; (2) in doing so, the virtuous person has the pleasantest life. In these claims Aristotle relies on his views about the nature of pleasure and its role in happiness (Nicomachean Ethics VII 11-14, X 1-5).

He denies that pleasure is some uniform sensation to which different kinds of pleasant action are connected only causally (in the way that the reading of many boring books on different subjects might induce the same feeling of boredom). Instead he argues that the specific pleasure taken in x rather than y is internally related to doing x rather than y, and essentially depends on pursuing x for x's own sake. Pleasure is a 'supervenient end' (1174b31-3) resulting from an activity that one pursues as an activity (praxis or energeia) rather than a mere process or production (kinesis or poiesis).

Aristotle insists, following Plato's Philebus, that the value of the pleasure depends on the value of the activity on which the pleasure supervenes (1176a3-29). The virtuous person has the pleasantest life, but the ppleasantest life cannot aim exclusively at pleasure.


Virtue, friendship and the good of others

The virtuous person's deliberation, identifying the mean in relation to different desires and different situations, is articulated in the different virtues of character (described in Nicomachean Ethics III-V). The different virtues are concerned with the regulation of non-rational desires (for example, bravery, temperance, good temper), external goods (for example, magnificence, magnanimity) and social situations (for example, truthfulness, wit). Some concern the good of others to some degree (bravery, good temper, generosity).

Aristotle's Greek for virtue of character, ethikearete, is rendered into Latin as 'virtus moralis'. The English rendering 'moral virtue' is defensible, since the virtues of character as a whole display the impartial concern for others that is often ascribed to morality. They are unified by the aim of the virtuous person, who decides on the virtuous action because it is 'fine' (kalon). Fine action systematically promotes the good of others; we must aim at it if we are to find the mean that is characteristic of a virtue (1122b6-7).

A second unifying element in the virtues, inseparable from concern for the fine, is their connection to justice (V 1-2). Aristotle takes justice to be multivocal, and distinguishes general justice from the specific virtue concerned with the prevention and rectification of certain specific types of injustices. General justice is the virtue of character that aims specifically at the common good of a community. Since it is not a different state of character from the other virtues, they must incorporate concern for the common good.

To explain why concern for the good of others, and for a common good, is part of the life that aims at one's own happiness, Aristotle examines friendship (philia; Nicomachean Ethics VIII-IX). All three of the main types of friendship (for pleasure, for advantage and for the good) seek the good of the other person. Only the best type - friendship for the good between virtuous people - includes A's concern for B's good for B's own sake and because of B's essential character (Nicomachean Ethics VIII 1-4).

In the best sort of friendship, the friend is 'another self'; A takes the sorts of attitudes to B that A also takes to A. Aristotle infers that friendship is part of a complete and self-sufficient life (IX 9-11). Friendship involves sharing the activities one counts as especially important in one's life, and especially the sharing of reasoning and thinking. Friends cooperate in deliberation, decision and action; and the thoughts and actions of each provide reasons for the future thoughts and actions of the other. The cooperative aspects of friendship more fully realize each person's own capacities as a rational agent, and so promote each person's happiness. Hence the full development of a human being requires concern for the good of others.


Two conceptions of happiness?

Although Aristotle emphasizes the other-regarding, social aspects of happiness, he also advocates pure intellectual activity (or 'study', the>ria) - the contemplation of scientific and philosophical truths, apart from any attempt to apply them to practice (Nicomachean Ethics X 6-8). The connection between the human function and human happiness implies that contemplation is a supremely important element in happiness. For contemplation is the highest fulfilment of our nature as rational beings; it is the sort of rational activity that we share with the gods, who are rational beings with no need to apply reason to practice. Aristotle infers that contemplation is the happiest life available to us, in so far as we have the rational intellects we share with gods.

According to one interpretation, Aristotle actually identifies contemplation with happiness: contemplation is the only non-instrumental good that is part of happiness, and the moral virtues are to be valued - from the point of view of happiness - simply as means to contemplation. If this is Aristotle's view, it is difficult to see how the virtues of character are even the best instrumental means to happiness. Even if some virtuous actions are instrumental means to contemplation, it is difficult to see how the motives demanded of the virtuous person are always useful, rather than distracting, for those who aim at contemplation.

Probably, however, Aristotle means that contemplation is the best component of happiness. If we were pure intellects with no other desires and no bodies, contemplation would be the whole of our good. Since, however, we are not in fact merely intellects (Nicomachean Ethics 1178b3-7), Aristotle recognizes that the good must be the good of the whole human being. Contemplation is not the complete good for a human being.

If this is Aristotle's view, then contemplation fits the conception of happiness that is upheld in the rest of the Nicomachean Ethics and in the other ethical works. The virtues of character, and the actions expressing them, deserve to be chosen for their own sakes as components of happiness. In the virtuous person, they regulate one's choice of other goods, and so they also regulate one's choices about contemplation. The Politics may be taken to develop this conception of happiness, since (in book VII) it sets contemplation in the context of a social order regulated by the moral virtues.


Selected bibliography

Ackrill, J.L. (1981) Aristotle the Philosopher, Oxford: Oxford University Press. (This and Barnes (1982) are the best short introductions.)

Barnes, J. (1982) Aristotle, Oxford: Oxford University Press.

Broadie, S.W. (1991) Ethics with Aristotle, Oxford: Oxford University Press. (This and Hardie (1980) are the best general guides to the Ethics; Hardie is more accessible to a beginner.)

Hardie, W.F.R. (1980) Aristotle's Ethical Theory, Oxford: Oxford University Press, 2nd edn. (Alongside Broadie (1991), one of the best general guides to the Ethics.)

Kraut, R. (1989) Aristotle on the Human Good, Princeton, NJ: Princeton University Press. (Clear and full discussion of happiness in Nicomachean Ethics I, X.)

Copyright: Routledge Encyclopedia of Philosophy, Version 1.0, London: Routledge
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Copyright 2002 (first published 1/96)