Abstract: Small, homogeneous communities in medieval and early modern times were able to make consensual social choices by voting with relatively broad voting rights. In complex societies in modern times, the enlargement of the electorate until introducing universal suffrage rights was developed with different enfranchisement paces, electoral rules, and party systems, producing different degrees of political instability.

Keywords: consensus, electoral rules, electorate, enfranchisement, political instability, political parties, social choice, universal suffrage, voting rights,