Final answer:
The concept that every member of society, including the leader, must follow the rules is part of the social contract theory, which is fundamental to a democratic society.
Step-by-step explanation:
The idea that every member of society must follow the rules, including the leader, reflects a key principle of the social contract. This philosophical concept suggests that people live together in society in accordance with an agreement that establishes moral and political rules of behavior. The social contract theory is evident in democratic systems, where a general will is created and agreed upon by the populace, illustrating a republican democracy in which even the leaders are subject to the same laws and regulations as the citizens. In a sense, everyone, including the sovereign, has a duty to uphold the agreed-upon laws, which contrasts with concepts such as totalitarianism or authoritarianism where rulers are not necessarily bound by the same set of rules as the citizens.