<P> A semi-presidential system is a system of democracy in which the government includes both a prime minister and a president . The particular powers held by the prime minister and president vary by country . </P> <P> Some modern democracies that are predominantly representative in nature also heavily rely upon forms of political action that are directly democratic . These democracies, which combine elements of representative democracy and direct democracy, are termed hybrid democracies, semi-direct democracies or participatory democracies . Examples include Switzerland and some U.S. states, where frequent use is made of referendums and initiatives . </P> <P> The Swiss confederation is a semi-direct democracy . At the federal level, citizens can propose changes to the constitution (federal popular initiative) or ask for a referendum to be held on any law voted by the parliament . Between January 1995 and June 2005, Swiss citizens voted 31 times, to answer 103 questions (during the same period, French citizens participated in only two referendums). Although in the past 120 years less than 250 initiatives have been put to referendum . The populace has been conservative, approving only about 10% of the initiatives put before them; in addition, they have often opted for a version of the initiative rewritten by government . </P> <P> In the United States, no mechanisms of direct democracy exists at the federal level, but over half of the states and many localities provide for citizen - sponsored ballot initiatives (also called "ballot measures", "ballot questions" or "propositions"), and the vast majority of states allow for referendums . Examples include the extensive use of referendums in the US state of California, which is a state that has more than 20 million voters . </P>

Which of the following principles is most fundamental to democratic theory