Refer to the passage. No man is allowed to be a judge in his own cause,
because his interest would certainly bias his judgment,
and, not improbably, corrupt his integrity. With equal, nay
with greater reason, a body of men are unfit to be both
judges and parties at the same time; yet what are many
of the most important acts of legislation, but so many
judicial determinations, not indeed concerning the rights
of single persons, but concerning the rights of large
bodies of citizens? Justice ought to hold the
balance between them. Yet the parties are, and must be,
themselves the judges; and the most numerous party,
or, in other words, the most powerful faction must be
expected to prevail.
Federalist, no. 10,
James Madison

What is Madison's primary argument in this passage?

Polítical parties can be trusted to work for the greater
good.

Political parties are not factional and do not represent
factions.

Parties are balancing agents that work to undo local
self-interest in a federal context.

The strongest or most populous faction will win and
proceed to make decisions in their own favor.