What key element did John Locke's philosophy introduce to modern political thought?

John Locke's philosophy significantly contributed to modern political thought through the importance of social contracts. Locke argued that legitimate government is based on an agreement between the governed and the government, where individuals consent to surrender some of their freedoms in exchange for the protection of their remaining rights. This concept of a social contract laid the foundation for democratic governance, emphasizing that authority is derived from the consent of the governed. It challenged the view of monarchy as a divine right and established the principle that government must serve the people and be accountable to them, influencing later democratic frameworks and philosophies, including those of the Enlightenment and the formation of modern democratic states.

The other options represent ideas that are important in their own right but do not directly reflect a central tenet of Locke's political philosophy. The right to bear arms, separation of church and state, and the idea of a governed state are significant in their contexts, but the emphasis on social contracts fundamentally shaped the way political authority and citizenship are understood in the framework that Locke provided.