The kyklos (Ancient Greek: κύκλος [kýklos], "cycle") is a term used by some classical Greek authors to describe what they considered as the cycle of governments in a society. It was roughly based on the history of Greek city-states in the same period. The concept of the kyklos is first elaborated by Plato, Aristotle, and most extensively Polybius. They all came up with their own interpretation of the cycle, and possible solutions to break the cycle, since they thought the cycle to be harmful. Later writers such as Cicero and Machiavelli commented on the kyklos.


Plato describes his version of the kyklos in his work Republic, Book VIII and IX.[1] He distinguishes 5 forms of government: aristocracy, timocracy, oligarchy, democracy, and tyranny, and writes that governments devolve respectively in this order from aristocracy into tyranny. Plato's cycle of governments is linked with his anthropology of the rulers that come with each form of government. This philosophy is intertwined with the way the cycle of governments plays out.[2] An aristocracy is ruled by aristocratic people whose rule is guided by their rationality. The decline of aristrocracy into timocracy happens when people who are less qualified to rule come to power. Their rule and decision-making is guided by honor. Timocracy devolves into oligarchy as soon as those rulers act in pursuit of wealth; oligarchy devolves into democracy when the rulers act on behalf of freedom; and lastly, democracy devolves into tyranny if rulers mainly seek power. Plato believes that having a philosopher king, and thus having an aristocratic form of government is the most desirable.[3]


Aristotle writes about the cycle of governments in his Politics.[4] He believes the cycle begins with monarchy and ends in anarchy, and that it does not start anew. He also refers to democracy as the degenerate form of rule by the many and calls the virtuous form politeia, which is often translated as constitutional democracy.

All the philosophers believed that this cycling was harmful. The transitions would often be accompanied by violence and turmoil, and a good part of the cycle would be spent with the degenerate forms of government. Aristotle gave a number of options as to how the cycle could be halted or slowed:

  • Even the most minor changes to basic laws and constitutions must be opposed because over time the small changes will add up to a complete transformation.
  • In aristocracies and democracies the tenure of rulers must be kept very short to prevent them from becoming despots
  • External threats, real or imagined, preserve internal peace
  • The three government basic systems can be blended into one, taking the best elements of each
  • If any one individual gains too much power, be it political, monetary, or military he should be banished from the polis
  • Judges and magistrates must never accept money to make decisions
  • The middle class must be large
  • Most important to Aristotle in preserving a constitution is education: if all the citizens are aware of law, history, and the constitution they will endeavour to maintain a good government.


According to Polybius, who has the most fully developed version of the kyklos, it rotates through the three basic forms of government: democracy, aristocracy, and monarchy, and the three degenerate forms of each of these governments: ochlocracy, oligarchy, and tyranny. Originally society is in ochlocracy but the strongest figure emerges and sets up a monarchy. The monarch's descendants, who lack virtue because of their family's power, become despots and the monarchy degenerates into a tyranny. Because of the excesses of the ruler the tyranny is overthrown by the leading citizens of the state who set up an aristocracy. They too quickly forget about virtue and the state becomes an oligarchy. These oligarchs are overthrown by the people who set up a democracy. Democracy soon becomes corrupt and degenerates into ochlocracy, beginning the cycle anew. Polybius's concept of the cycle of governments is called anacyclosis.

Polybius, in contrast to Aristotle, focuses on the idea of mixed government: the idea that the ideal government is one that blends elements of monarchy, aristocracy, and democracy. Aristotle mentions this notion but pays little attention to it. Polybius saw the Roman Republic as the embodiment of this mixed constitution, and this would explain why the Roman Republic was so powerful and why it would remain stable for a longer amount of time.[5] Polybius' description of the anacyclosis can be found in Book VI of his Histories.[6]


Cicero describes anacyclosis in his philosophical work De re publica.[7] His version of the anacyclosis is heavily inspired by Polybius' writings. Cicero argues, contrary to Polybius, that the Roman state can prevail and will not succumb to the harmful cycle despite its mixed government, as long as the Roman Republic will return to its ancient virtues (mos maiorum).[8]


Machiavelli, writing during the Renaissance, appears to have adopted Polybius' version of the cycle. Machiavelli's adoption of anacyclosis can be seen in Book I, Chapter II of his Discourses on Livy.[9] Although Machiavelli adopts the idea of the circular structure in which types of governments alternate, he does not accept Polybius' idea that the cycle naturally devolves through the exact same pattern of governments.[10]


  1. ^ Plato (1969). "VIII, IX". Republic. Translated by Shorey, Paul. Harvard University Press.
  2. ^ G.A. Plauche (2011). The Cycle of Decline of Regimes in Plato's Republic.
  3. ^ R. Polin (1977). Plato and Aristotle on Constitutionalism: An Exposition and Reference Source. Ashgate Publishing. ISBN 978-1840143010.
  4. ^ Aristotle (1944). "V". Politics. Translated by Rackham, H. Harvard University Press.
  5. ^ M.A. Hermans (1991). "Polybius' Theory of the Anacyclosis of Constiturions" (PDF). Cite journal requires |journal= (help)
  6. ^ Polybius (1889). "VI". The Histories. Translated by Shuckburgh, Evelyn. Macmillan.
  7. ^ Cicero (1928). De re publica. Translated by Keyes, C.W.
  8. ^ Beek, Aaron L. (2011). "Cicero Reading Polybius".
  9. ^ Machiavelli (1883). "I:2". Discourses on Livy.
  10. ^ Del Lucchese, Filippo (2015). The Political Philosophy of Niccolò Machiavelli. Edinburgh University Press. pp. 32–34. ISBN 978-1-47440429-7.