Aristotle’s Philosophy of Law

Aristotle was born in 384 B.C. at Stagira in northern Greece, the son of Nicomachus, a physician of King Amyntas II of Macedonia. At age seventeen he entered Plato’s Academy in Athens, where he studied for nineteen years. In addition to composing a number of dialogues now lost, he may have then begun work on his Rhetoric. After Plato’s death (348) Aristotle grew alienated from the school and soon after left Athens. He resided at Assos, where he married Pythias, the niece of the philosophically trained tyrant Hermeias, and then lived at Mytilene on Lesbos. In 343 he was invited by King Philip of Macedonia to educate his thirteen-year-old son Alexander. Subsequently, Philip and his successor, Alexander, defeated an alliance of Greek city-states, and most of Greece—including Athens—submitted to Macedonian hegemony while Alexander was conquering the Persian Empire. Aristotle returned to Athens in 335 after the death of Philip and became a metic (resident alien). He founded his school at the Lyceum outside the city and began the most productive stage of his career. He offered lectures on technical philosophy (logic, physics, and metaphysics) in the morning, and on more popular subjects (rhetoric, ethics, and politics) in the evening. He also collected a celebrated library, and with his students compiled descriptions of 158 constitutions. During this period he probably composed most of his greatest treatises, including much of the Politics. After his wife’s death he took a mistress, Herpyllis of Stagira, who gave birth to Nicomachus, after whom the Nicomachean Ethics was named. This work is probably Aristotle’s revision of an earlier work, the Eudemian Ethics, from which three books were reused (Eudemian Ethics, Books IV–VI becoming Nicomachean Ethics, Books V–VII).¹

After Alexander’s sudden death, the Athenians rose up against the Macedonians. Aristotle, who was a friend of Alexander’s viceroy, Antipater, bore the brunt of anti-Macedonian sentiment. Charged with impiety he left Athens lest she “sin twice against philosophy.” Appointing Theophrastus his successor as head of the Lyceum, Aristotle retreated to Chalcis, where he died soon after (322).

According to an ancient tradition, Aristotle’s writings were lost after his death and only rediscovered in the first century B.C. Andronicus of Rhodes assembled numerous papyrus scrolls into treatises, which were recopied in manuscripts over two millennia. Consequently, the works of Aristotle as we now have them raise many difficulties. This applies to the major works that contain Aristotle’s legal philosophy: the Politics, the Nicomachean Ethics, and the Rhetoric. In the case of each of these works, scholars debate over the following questions: Were the parts of this work written at roughly the same time or do they express Aristotle’s thought at different stages of his life? Does the organization of the work reflect Aristotle’s intention or is it the construction of a later editor (which may be contrary to what Aristotle intended)? Does the work as it now exists express a coherent philosophical position? Moreover, another work that contains material on the law, Magna Moralia, may have been written not by Aristotle but by an early member of his school. An early spurious work, Rhetoric to Alexander, also contains some relevant material. Finally, Aristotle’s 158 constitutions vanished altogether except for scattered quotations, until the rediscovery of a major fragment of the Constitution of Athens in the late nineteenth century. This work may also have been written by an early student of Aristotle during his lifetime.

The concept of law is deeply embedded in Aristotle’s political philosophy. Although legal terminology occurs frequently in his writings, Aristotle does not himself present a systematic and unitary legal treatise. Not infrequently he quotes (or paraphrases) others and appropriates their remarks, which results in considerable imprecision and apparent inconsistency in his various characterizations of law. He identifies law in different places with reason, with agreement, and with order. A reconstruction of Aristotle’s legal philosophy should explain how these different characterizations are interrelated.

Aristotle’s main term for “law” is the noun nomos (plural nomoi). Related expressions are kata ton nomon, “according to the law,” nomikos, “legal,” and nomimos, “lawful.” The noun nomimon can also have the sense of “statute.” In contrast, para ton nomon signifies “against the law,” and paranomos means “illegal” or “unlawful.” The precise meanings of these terms vary with the context. Sometimes Aristotle speaks of written law, in contrast to unwritten custom (ethos), for example, that one should honor one’s parents, do good to one’s friends, and return good to one’s benefactors (Pol. III.16.1287b5–8; EN X.9.1180b4; cf. Pseudo-Aristotle, Rhet. Al. 1.1421b35–1422a1). But he also distinguishes between unwritten law and written law (Pol. VI.5.1319b40; EN X.9.1180a35; Rhet. I.10.1368b7, I.13.1373b4). He also uses nomos more loosely for “convention,” the sense in which nomos was opposed to phusis (“nature”) by the sophists (SE 12.173a7–30). Aristotle’s term nomos can denote either a particular law or the law in an abstract sense.

A particular law is a rule (kanôn) prescribing or prohibiting various kinds of actions (see EN I.2.1094b5). For example, it commands the citizens not to leave their posts in time of war, not to commit adultery or act abusively, not to hit or slander others, and so forth (see EN V.1.1129b19–23). Because they command and prohibit general classes of action, the laws are universal in form: “The law speaks universally” (EN V.10.1137b13, 20; cf. 7.1135a5–8). The universality of the laws has an obvious advantage: The citizens can learn what the laws require, adapt their behavior to them, and acquire the habit of obedience.

But because laws are universal, they cannot address unusual cases. For example, the assembly might want to bestow honorary citizenship on a foreign potentate who has come to the aid of the city-state (polis). This requires an ad hoc rule. In an authoritarian regime this is called an “edict” (epitagma), and in a popular constitution a “decree” (psêphisma). Such rules concern individual acts to be done (EN VI.8.1141b27–8); they cannot be universal (Pol. IV.4.1292a37).

What distinguishes a universal rule as a law? This is the question, “What is law?” in the abstract sense, which Aristotle does not address in a systematic fashion in our extant texts, although there is considerable evidence as to how he would answer it: Law is “a sort of order” (Pol. VII.4.1326a30; cf. III.16.1287a18; II.5.1263a23). Unfortunately, Aristotle does not explain this claim, but we can gather what it means by considering how he understands order in his metaphysical works. Order is a ratio or proportion of opposites (Phys. VIII.1.252a14–15). Aristotle illustrates the concept of order in his discussion of the atomist theorists Democritus and Leucippus, who distinguished order from the relations of position and shape. For example, A differs from N in shape, AN from NA in order, and A from in position (cf. Metaph. I.4.985b17; Phys. I.5.188a24). As this illustration indicates, order is a ratio or proportion of prior and posterior elements (cf. Metaph. VII.12.1038a33). In a social context the fundamental type of priority is that of ruler to ruled:

Whenever a thing is established out of a number of things and becomes a single common thing, there always appears in it a ruler and a ruled. (This is true whether it is formed out of continuous or discrete parts.) This [relation of ruler and ruled] is present in living things, but it derives from all of nature. For even in things that do not have a soul there is a sort of rule, for example, of harmony. (Pol. I.5.1254a28–33)

According to this principle of rulership, social order must be produced and maintained by a ruling element. This assumption reflects the link between the Greek noun, taxis, “order” (“arrangement,” “organization,” etc.), and the verb, tassein, “to order” (“to command,” “to arrange,” etc.). Similarly, in a living organism the soul is the natural ruler and authority over the body (de An. I.5.410b10–15; cf. Plato, Phd. 79e–80a). Aristotle also compares the order of the entire cosmos to that of an army; just as military order is due to the general, cosmic order is due to God. In both cases the parts are organized for the sake of a single end (Metaph. XII.10.1075a13ff.).

Given that law is a kind of order, where does it come from? Aristotle recognizes two different causes of order: nature and reason. In the physical world, outside of human creation, “nature is everywhere the cause of order” (Phys. VIII.1.252a12). Aristotle here understands “nature” (phusis) in terms of his teleological theory that entities have natural ends. Nature provides an internal directing principle, which causes a body to move or remain at rest in a regular manner (Phys. II.1.192b20–3). For example, an acorn grows by nature into an oak tree. Because of its internal nature the acorn grows in an orderly manner. Hence, “order is the proper nature of perceptible objects” (Cael. III.2.301a5–6). That is, orderliness is the natural condition of things (GA III.10.760a31), and disorderliness is unnatural (Cael. III.2.301a4–5). In the realm of human production, however, it is reason rather than nature that does the ordering (see EN III.12.1119b17). For example, a builder conceives of a form of a house and imposes this form upon a heap of bricks, constructing the house through a definite sequence of stages: foundations, walls, roof, etc. If, then, all order is due either to nature or to human reason, which of these is the cause of law?

For Aristotle, the primary source of law is reason embodied in a human legislator. The Constitution of Athens describes Solon’s legislative activity at the beginning of the sixth century B.C.:

Next Solon established a constitution and laid down other laws; and they stopped observing the ordinances of Draco, except those relating to murder. They wrote up the laws on the wooden tablets [mounted on pillars revolving on an axis], and set them up in the Stoa (porch) of the Basileus, and everyone swore to observe them. And the nine archons used to swear an oath upon the stone, declaring that they would dedicate a golden statue if they transgressed any law. This is the origin of the oath to that effect which they take to the present day. Solon fixed his laws for a hundred years, and he ordered the constitution in the following manner […]. (Ath. 7.1–2)

Nomothetês, the Greek word for “legislator,” derives from nomos, “law,” and tithenai, “to lay (down).” The name “legislator” thus implies that the laws owe their existence to a human producer, who is also compared to a “craftsman” (dêmiourgos) of the laws or constitution (EN X.9.1180a21–2; Pol. II.12.1273b32–3). Like a weaver or shipbuilder, the legislator imposes a certain form on his materials, in particular, on the population of the city-state (Pol. VII.4.1325b40–1326a5). The legal order resembles cosmic order caused by God (1326a29–34). Legislators include the founders of constitutions, such as Lycurgus of Sparta and Solon of Athens, as well as assemblies or magistrates who lay down particular laws, unwritten as well as written (Pol. IV.1.1289a22, 14.1298a17; VI.5.1319b40; EN X.9.1180a35–b1).

Aristotle would have rejected the notion of “spontaneous order” espoused by some modern social scientists. He criticizes the theories of some pre-Socratic philosophers that the order of the cosmos arose by chance from earlier events, because he holds that regular outcomes cannot result from chance events: “chance is a cause in a disorderly or haphazard way” (MM II.8.1206b39–1207a1; cf. Phys. II.4.196a24–b5, 8.198b34–6, and Cael. III.2.301a10). If order does not arise by nature, order can only be due to rational design. Consequently, Aristotle would have dismissed the suggestion that legal order evolves spontaneously through myriad human interactions, as if (but not in fact) “by an invisible hand.”

Aristotle also recognizes, however, that the legal order can subsist only if the citizens are law abiding. He thus characterizes law as a kind of common agreement (homologia) (Pol. I.6.1255a6) and as, “on the whole, a sort of convention [sunthêkê]” (Rhet. I.15.1376b9–10; cf. Pol. III.9.1280b10–11). His point is not that law is merely conventional, but that ruling according to law goes hand in hand with being ruled voluntarily (Pol. IV.10.1295a15–16). Furthermore, he states: “The law has no power to command obedience except that of habit” (Pol. II.8.1269a20–1). Habitual obedience is a precondition of the “compulsive power” of the law (mentioned at EN X.9.1180a21). But how is the claim that law results from agreement to be reconciled with the thesis that reason is the source of law? The answer may be sought in Aristotle’s distinction between a strict cause and a contributing cause (sunaition). For example, he argues that heat is a contributing cause—but not the strict cause—of biological growth, because it does not determine when the process is complete (de An. II.4.416a14). Similarly, the laws of Athens required the general agreement of the Athenian citizens if they were to have the force of law. Solon’s constitution, in fact, soon failed partly due to the wealthy class’s general “dissatisfaction with the constitution because of the great change that had occurred” (Ath. 13.3). The contributions of reason and agreement are both recognized in the Aristotelian Rhetoric to Alexander: “Law, simply described, is reason [logos] defined according to the common agreement [homologia] of the city-state, regulating action of every kind” (1.1420a25; cf. 1422a2–3, 2.1424a9–12).

The purpose of law must be understood in relation to the constitution. The following passage makes clear that the study of law is subordinate to constitutional theory:

The laws ought to be laid down (and everybody does lay them down) with a view to the constitutions, but not the constitutions to the laws. A constitution is the ordering [taxis] of offices in city-states: in what way the offices are distributed, what element has authority in the constitution, and what is the end of each community. But the laws which are separate from those revealing the constitution are those according to which the magistrates should rule and guard against violators of them. (Pol. IV.1.1289a13–20)

Like law, the constitution (politeia) is a sort of “order” (cf. Pol. III.1.1274b38), which provides the answer to three questions: (1) How are political offices distributed? (2) What is the sovereign or authoritative element? (3) What is the end of the city-state? Aristotle devotes considerable attention to the first two questions, and, from this viewpoint, the constitution is identified with the government (politeuma) (III.6.1278b8–11). Hence, some translators render politeia as “regime.” But insofar as politeia signifies the order or “form” of the city-state (III.2.1276b7), it corresponds to “constitution.” Although the Greek city-states did not have written constitutions in the modern sense, the constitutions were often administered by means of written laws, as in the case of Solon. The above passage (IV.1.1289a13–20) distinguishes three kinds of laws: laws that reveal the constitution, that is, laws regarding the orderly selection of officials (cf. III.16.1287a18); laws administered by magistrates, presumably to maintain order among the citizenry; and laws concerning the prevention and punishment of crime. Such laws are necessary: “The salvation of the city-state depends on the laws” (Rhet. I.4.1360a19–20; cf. Pol. V.9.1310a34–6). And “where the laws have no authority,” Aristotle declares, “there is no constitution” (Pol. IV.4.1292a32). Yet the laws are subordinate to the constitution, and the constitution is the first concern of the legislator (III.1.1274b37).

The constitution has to do with the end or goal of the city-state. This is correctly defined by the basic principles of Aristotle’s political philosophy: First, the city-state exists for the sake of the good life or happiness (Pol. I.2.1252b30, III.9.1281a1–2). Hence, the legislator should try to fashion laws that will tend to produce and protect happiness and its components for the political community (see EN V.1.1129b17–25). Second, the best life or happiness consists of a life of virtuous activity (EN I.7.1098a16; Pol. III.9.1281a2–3, VII.1.1323b40– 1324a2). Therefore, the highest purpose of the legislator is to make the citizens virtuous (EN X.9.1180b23–5). When the laws are “laid down correctly,” they command the citizens “to live according to each excellence and [forbid] us to live according to each vice” (V.2.1130b23–4, 1.1129b23–5). From this standpoint the constitution is “the way of life of the city-state” (Pol. IV.11.1295a40). Citizens who are habituated under the laws acquire self-ruling souls: that is, they are governed by reason rather than appetite. Having internalized the law, a virtuous individual becomes “a law unto himself” (EN IV.8.1128a32; Pol. III.13.1284a13).

Just as a doctor accepts as a given that health is his aim, “a statesman does not deliberate about whether he shall produce good law, nor does any one else deliberate about his end” (EN III.3.1112b14–15; cf. EE I.5.1216b18; cf. Pol. III.9.1280b6). Good law (eunomia) is defined in normative terms: “[L]aw is a certain order, and good law is good order” (Pol. VII.4.1326a29–31). By “good law,” however, Aristotle means not merely that the laws are good, but that the city-state is in a good legal condition:

Good law does not consist in laying down good laws, if they are not obeyed. We must therefore suppose that good law in one way consists in the actual obedience to the laws that have been framed, and in another way it consists in the fact that the laws that are actually obeyed are laid down nobly (for laws laid down badly can also be obeyed). (Pol. IV.8.1294a3–7; cf. MA 10.703a30–4)

A city-state with good law is like a virtuous person who knows the right thing to do and acts accordingly. But it may happen that a legislator frames good laws that the citizens fail to obey. For example, the Athenians did not abide by the constitution of Solon, and the tyrant Pisistratus soon after rose to power (see Ath. 13–14). Such an inconstant city-state resembles a morally weak person: “[I]t passes the decrees it should and has excellent laws, but makes no use of them” (EN VII.10.1152a20–1).

There is thus a close connection among Aristotle’s different characterizations of law as “order,” “reason,” and “agreement.” Laws are general rules that produce a kind of order in the actions and desires of the citizens, which are devised in a rational manner by a legislator, and which are effective only if the governed accept and obey them. Because legislation is a rational activity, it is the appropriate subject for an Aristotelian science.

The special science called “legislative” (nomothetikê) belongs to the second of the three main Aristotelian divisions of the sciences: contemplative, practical, and productive (Top. VI.6.145a15–16; Metaph. VI.1.1025b25, XI.7.1064a16–19; EN VI.2.1139a26–8). Each has a distinctive aim. The end of contemplative thought (e.g., physics, mathematics, and theology) is knowledge or truth for its own sake; the end of productive thought (e.g., poetry, medicine, and architecture) is the creation of an object distinct from the productive activity; and the end of practical thought is good action for its own sake. “Practical” thought is so called because it aims at action (praxis). The excellence of practical thought is practical wisdom or prudence (phronêsis), which issues in true judgments about actions that are good or bad for a human being (cf. EN VI.5.1140b4–6). This has three subtypes: practical wisdom concerned with the individual, economics (oikonomikê) concerned with the household (oikos), and political science (“politics” for short) concerned with the city-state. Politics includes legislative science (nomothetikê) and politics in a more familiar sense, involving everyday political activities such as deliberation and adjudication (EN VI.8.1141b29–33; EE I.8.1218b12–14). The latter are concerned with particular circumstances; for example, a judge must determine whether a particular crime was committed or not (Rhet. I.1.1354b13–15). Thus, legislative science is a part of politics (EN X.9.1180b30–1). Aristotle conjoins the term “legislator” with “statesman” (politikos) (Pol. III.1.1274b37, IV.1.1288b27, V.9.1309b35; cf. EN I.13.1102a7–10), and he likens the laws to “acts [erga] of political science” (EN X.9.1181a23).

Aristotle views legislative science as the capstone of politics:

Of the practical wisdom concerned with the city-state, the practical wisdom which plays a controlling role is legislative, while that which is related to this as particulars to their universal is known by the common name of “political.” This is capable of action and deliberation, for a decree is a thing to be carried out in the form of an individual act. That is why the exponents of this art are alone said to take part in politics; for these alone do things as manual laborers do things. (EN VI.8.1141b24–9)

Aristotle discusses in Politics IV.1–2 the tasks of “the legislator and true statesman” (1288b27). Any complete science or craft must study a wide range of issues concerning its subject matter. Political (i.e., legislative) science studies a range of constitutions (1288b21–35): not only the ideal constitution, but also inferior systems. “For it is probably impossible for many persons to attain the best constitution, so that the legislator and true statesman must overlook neither the best constitution without qualification nor the best under the circumstances” (1288b24–7). The legislator must be acquainted with three sorts of constitution: first, the best without qualification, that is, “most according to our prayers with no external impediment” (1288b23–4); second, the best under the circumstances for a given population; third, the constitution that serves the aim a given city-state population happens to have that is best based on a hypothesis:

[F]or [the political scientist] ought to be able to study a given constitution, both how it might originally come to be, and, when it has come to be, in what manner it might be preserved for the longest time; I mean, for example, if a particular city happens neither to be governed by the best constitution, nor to be equipped even with necessary things, nor to be the [best] possible under existing circumstances, but to be a baser sort. (1288b28–33)

Aristotle distinguishes between correct constitutions, which promote the common advantage, from deviant constitutions, which promote the advantage of the rulers, and combines this with the observation that the ruling class may consist of one person, a few, or a multitude. Hence, there are six basic constitutional forms (Pol. III.7):

The above sixfold schema² is only the starting point for Aristotle’s classification of constitutions, because there are many varieties of each type. A large democracy like Athens might include wealthy landed aristocrats, farmers, craftsmen, merchants, sailors, fishermen, and manual laborers. The character of the democracy would depend upon the relative power of these different classes (IV.3.1290a8). Aristotle distinguishes a range of democratic constitutions that might arise, from a moderate form with a modest property qualification (excluding the “baser” sort of citizen) to an extreme form, which included all freeborn persons no matter how poor and uneducated who were susceptible to demagoguery (IV.4.1291b14–1292a13). In general, “the legislator and statesman ought to know what democratic measures save and what destroy a democracy, and what oligarchic measures save or destroy an oligarchy” (Pol. V.9.1309b35). This requires knowledge of the different sorts of constitutions and how these can be combined to become “mixed” constitutions of various sorts (Pol. IV–VI). Aristotle’s view is, again, open to different interpretations: Should legislators try to bring about genuine reform, making actual democracies or oligarchies more like the ideal constitution? Or should they strive for quasi-reform, making them more stable and viable constitutions of their type, even if they are not more just?

Education is the other major concern of legislative science. For the legislator has not completed his job by merely laying down good laws. As the unfortunate example of Solon shows, the citizens may not be disposed to obey the laws. Threats of punishment are not in Aristotle’s view a sufficient guarantee that the citizens and officials will support the constitution and laws (see Pol. IV.5.1292b11–17). The laws themselves thus must have an educative function: “Whoever wants to make people, whether many or few, better by his care must try to become capable of legislating, if it is through laws that we can become good” (EN X.9.1180b23–5). Aristotle argues as follows: Rational moral arguments involve an appeal to goodness or nobility. People will be motivated only by pleasure or pain unless their souls have first been cultivated “like earth which is to nourish seed,” that is, unless they have been taught by habit to love the good and noble and to hate the evil and base (1179b25–6). They will come to recognize the inherent value of virtue only by performing virtuous actions repeatedly, so that they acquire the habit of acting virtuously. Hence, they will not respond to rational moral arguments unless they have first been morally habituated. Further, those who have not yet been morally habituated will only respond to “compulsive power,” which commands have only when they are backed by the law (1180a21). Therefore, people can be morally educated only if they are habituated under the laws.

Because legislative science has an important pedagogical function, Aristotle devotes over half of his discussion of the ideal constitution to its educational system (Pol. VII–VIII). The legislator must be knowledgeable of human nature and cognizant of the diversities of human lives and actions as he designs a system of education that will promote the development of the citizens’ bodies and souls (VII.14.1333a37–41, 15.1334b6–28). There must be a detailed program of prenatal and infant care, physical education, and liberal education, including letters, mathematics, and music. The educational system must be public in view of the fact that the citizens have a single common end, the life of moral virtue, which can be achieved only if every citizen is educated (VII.13.1332a31–6; VIII.1.1337a21–6). But education in civic virtue is also necessary for deviant constitutions. “The most beneficial laws, even though they are ratified by everyone in the government, will be of no benefit, unless the people are habituated and educated in the constitution, democratically, if the laws are democratic, and oligarchically, if the laws are oligarchic” (Pol. V.9.1310a14–18).

Even when there is not a system of public education, private citizens should undertake to educate their children and friends, and they will do so more effectively if they are capable of legislating. “For it is clear that public care comes about through laws, and reasonable care through excellent laws. And it would seem to make no difference whether the laws are written or unwritten, nor whether an individual or many persons are educated through them” (EN