What belongs (is part of) you, and what is not? Where is the boundary?
Socrates is defending a neo-Pythagorean position, while the two guys who were introduced as neo-Pythagoreans are not.
In the middle of the dialog there is a crisis, where the arguments are so good that the idiots can’t say anything, and then Socrates gets called in and he absolutely obliterates everything and everyone and he is very smart and cool