Cicero · Politics

The Mixed Constitution

Cicero’s defence of the Roman republic as the best form of government - a balanced mixture of monarchy, aristocracy, and democracy that checks the corruption to which each pure form decays.

From the lesson

Cicero, drawing on the Greek historian Polybius and on Plato and Aristotle before him, asked the oldest question of political philosophy: what is the best form of government? The ancients identified three basic ‘pure’ forms - monarchy (rule by one), aristocracy (rule by the best few), and democracy (rule by the many) - each with its own virtue. Monarchy provides unity and decisive leadership; aristocracy provides wisdom and experience; democracy provides liberty and the consent of the people. Each, Cicero grants, has something to recommend it. But each, he argues, also carries within it the seed of its own corruption - and so none of the pure forms, by itself, can provide stable and just government for long. The search for the best constitution must therefore look beyond the three pure forms to something that combines their strengths while guarding against their characteristic decay.

Cicero, following Polybius, describes a grim cycle (the anacyclosis) through which pure constitutions endlessly rotate and collapse. A good king degenerates into a tyrant; the tyrant is overthrown by the noble few, establishing an aristocracy; the aristocracy degenerates into a self-serving oligarchy; the oligarchy is overthrown by the people, establishing a democracy; the democracy degenerates into a lawless mob; and out of the chaos of mob rule, a strongman arises to impose order as a new king - and the whole cycle begins again. Each pure form, however well it begins, contains the principle of its own decay and is fated to degenerate and be overthrown, only to be replaced by another pure form destined for the same fate. This endless revolution of constitutions is, for Cicero, the great problem of political life - the instability that condemns societies to lurch from one form of government to its corruption and on to the next, never finding lasting peace and justice.

Cicero’s ideal constitution was not a theoretical construction but, he believed, an actual historical achievement: the Roman republic itself, in its best days. Rome, he argued, had stumbled by long experience and the wisdom of many generations onto the best constitution - the mixed government that combined all three pure forms in balance. The consuls, two annually elected magistrates with the power of command, supplied the monarchical element of unified leadership; the Senate, the council of experienced former magistrates, supplied the aristocratic element of wisdom and continuity; the popular assemblies and the tribunes of the plebs supplied the democratic element of the people’s liberty and consent. Each checked the others: the consuls could not become kings, for they were two, served only a year, and answered to the Senate and people; the Senate could not become an oligarchy, for it was checked by the consuls’ power and the tribunes’ veto; the people could not become a mob, for they were guided by the Senate and led by the consuls. This balance, Cicero held, was the secret of Rome’s stability and greatness - and its breakdown, in his own lifetime, was the tragedy he spent his life trying to prevent.

This is the opening of the lesson. The rest — the dialogue, the primary source, and the recall — is in the app.

What you'll be able to recall

You learned Cicero’s case that a mixed constitution, balancing the three pure forms, is the most stable and just. Eighteen centuries later, Montesquieu refined the idea into the separation of powers that shaped modern constitutions. State how Montesquieu developed it.

Leads to Montesquieu.

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