The declaration of independence reflects the principle of

Popular Sovereignty.

Explanation:

The principle of popular sovereignty state that it is the consent of the people that creates and sustains the state and its government through the elected representatives.

The people are source of all political power. this principle is associated with Thomas Hobbs, Rousseau and John Locke, all three were social contract philosophers. Declaration of independence also reflects this principle because it declare that it is the prole who instituted the government for themselves and it derives power from their consent.