In George Washington's farewell address, he said that political parties would do nothing but cause a division among the American people, and therefore advised America to not divide into factions.  Immediately after he died, the US divided into factions.  The factions divide people and make them change their ideologies so that they better fit the party that they associate themselves with.  In contrast, political parties trade off their party platforms so they can get more voters.  The flexibility of these political parties is a compromise between the two party system and Washington's no party system.  I know this is a stretch, but this flexibility between the parties keeps America from reaching a stalemate over issues.  This sort of thing happened when the democrats reached a deal with the republicans a couple week ago ending the shutdown. Washington did not get his wish of America not splitting into factions, but our political are capable of compromises which allows for progress