Final answer:
The speaker's use of a rhetorical question highlights the idea of self-sufficiency and fulfillment of basic needs in a good society.
Step-by-step explanation:
The speaker's use of a rhetorical question in this excerpt from The Republic by Plato emphasizes the idea that people in a good society will have everything they need.
By posing the question, 'will they not produce corn, and wine, and clothes, and shoes, and build houses for themselves?', the speaker implies that the people in this society are self-sufficient and capable of meeting their basic needs.
This supports the argument that a good society will provide its citizens with all the essentials for a comfortable life.