Here's why:
* The Third Estate was the largest and most burdened. This included everyone who wasn't nobility or clergy: peasants, urban workers, merchants, etc. They paid the most taxes, had the least representation in government, and faced significant economic hardship.
* The Third Estate sought greater representation and equality. They felt they were unfairly burdened by the privileges of the First (clergy) and Second (nobility) Estates. They wanted a more just system of taxation and representation.
* The Third Estate formed the National Assembly. This was a pivotal moment. After being locked out of the Estates-General, they declared themselves the legitimate representatives of the French people and began to enact reforms. This act of defiance directly challenged the existing power structure and set the revolution in motion.
It's important to note:
* The French Revolution was not just about the Third Estate. The First and Second Estates also had internal divisions, and some members of the nobility even joined the revolutionary cause.
* The revolution was fueled by multiple factors, including economic hardship, political inequality, Enlightenment ideas, and a weakening monarchy.
Therefore, while the Third Estate was a key catalyst, the French Revolution was the result of a complex interplay of factors and participants from all social classes.