1) Madison discusses how factions can undermine popular governments and analyses two methods to control their effects: removing their causes or controlling their consequences.
2) Removing the causes of faction, such as destroying liberty or enforcing uniformity of opinions, is impractical or tyrannical. Controlling the effects of faction is the better approach.
3) A large, extended republic helps control faction by making it more difficult for factions to form a majority due to the greater number of citizens and parties across a larger territory. This makes it harder for factions to unite and oppress others or act against the public good.