Final answer:
The theme stated and expanded upon in Federalist No. 10 is the issue of factions and their potential harm to the public interest and individual rights.
Step-by-step explanation:
The theme stated and expanded upon in Federalist No. 10 is the issue of factions and their potential harm to the public interest and individual rights. James Madison argues that factions, which are groups of people who gather to protect their special economic and political interests, can often work against the common good. Madison presents a solution to this problem by advocating for a large republic, where factions would be less likely to dominate and compromise would be reached through representation.
Learn more about Factions in Federalist No. 10 here: