Final answer:
The Enlightenment idea conveyed by the headline is the social contract theory which includes concepts such as the protection of natural rights, the legitimacy of government based on the consent of the governed, and the separation of powers to ensure checks and balances within a government.
Step-by-step explanation:
The Enlightenment idea represented by the headline 'social contract separation of powers checks and balances natural law' is primarily concerned with the social contract theory. This concept was a centerpiece of Enlightenment thinking about the role and authority of the state versus the rights of individuals. Prominent thinkers like John Locke, Jean-Jacques Rousseau, and Montesquieu elaborated on the social contract, with varying views on how it binds individuals to society and legitimates government authority.
For instance, Locke emphasized the protection of natural rights such as life, liberty, and property, and posited that a government's legitimacy is contingent upon its preservation of these rights. If a government fails to do so, citizens have the right to withdraw their obligation and seek a new government. Meanwhile, Rousseau introduced the concept of the general will, suggesting that legitimate political authority is derived from the collective agreement of the people. Montesquieu introduced the idea of the separation of powers within a government to prevent any one branch from becoming too powerful, influencing the checks and balances system in the U.S. Constitution.