It is false that primary sources are the only sources that historians use, since it is important to consult the works of other writers and historians to get an idea of how events in history have played out. Historians usually use a combination of secondary and primary sources.
The primary difference between the Federalists and the Anti-Federalists was that the former want to ratify the Constitution, which replaced the far "weaker" Articles of Confederation, while the latter wanted the states to have more power than the federal government.
Louis XVI´s decision to summon the estates-general prove disastrous because during it, the Third Estate , representing the Commoners decided to form a National Assembly, inviting the other two Estates ( Clergy and Nobility) to join them against the King. This is considered to be the start of the French Revolution.
