Who is Diotima Tuzzi in the novel, The Man Without Qualities II: The Like of It Now Happens?

Diotima is the wife of "the highest ranking commoner in all of Austria," the Permanent Secretary. While he attends to explicitly political work, she endeavors to pursue goals that are high, that also serve the country, and that are appropriate for a woman and for a woman of high status. This attitude has caused her to devise the Collateral Campaign.