What role did French philosophers play in the French Revolution?

My answer on Quora.

everal Important Philosophers spring to mind when discussing the French Revolution.

Voltaire -Influenced the anti-clericism of the revolution. Championed John Locke’s philosophy in the “Letters concerning the English Nation” (the notion of the Free Individual). This was called”the first bomb hurled against the “Old Regime”. Voltaire was a strong supporter of the radical English ideas of Liberty (now known as Classical Liberalism).

Baron Montesqueu - Favored a constitutional monarchy like England (which was essentially the tone of the first part of the Revolution). A nobleman himself he believed in a progressive and responsible nobility. His most famous work was “The Spirit of the Laws”

Denis Diderot - Champion of the Encyclopédie project along with Jean d’Alembert. Concerived nature as a creative process, stressed change and relativity of culture. Opponent of Bourgeois conformism. Favoured secularization of knowledge and a belief in science.

Jean-Jacques Rousseau - Father of the Romantic Movement. His writing concerning the Noble Savage (a longing for the Primitive) and the Social Contract impacted the Jacobins in particular. Emphasized the General Will and the need for the individual to subjugate themselves to the Collective, This would have dangerous consequences in the Reign of Fear but would become the dominant philosophy in the period from 1792–94. Views were to a great extent the antithesis of John Locke’s.

Other key philosophical ideas that impacted the Revolution from the Enlightenment were the notions that

1. Man is not innately depraved
2. The purpose of life was life itself not the after-life
3. Humanity had to be freed from ignorance and superstition
4. Progress and perfection is possible with individual liberty
5. All is interconnected through a type of benevolent Providence