Final answer:
The conventional argument for keeping men and women in separate spheres is based on maintaining social order and traditional roles. Plato disagrees with this argument and advocates for functional specialization and justice based on individual duties.
Step-by-step explanation:
The conventional argument for keeping men and women in separate spheres is rooted in ideas about maintaining social order and preserving traditional roles. The belief is that men and women have different strengths and abilities that are best suited to their assigned roles. Plato, on the other hand, seems to disagree with this argument. He believes in functional specialization and justice based on each individual doing their appointed duties, regardless of gender.