“This baby is like you, Crocus, still very young, and sometimes she doesn’t make much sense,” Sokrates said, smiling and tapping at her toes again.

“Sense?” I asked, carving the word in the flagstone at Sokrates’s feet.

“I heard what Lukretia said to you, and I understood what you were going to do. But we agreed that you would work for ten hours a day, and those ten hours are done for today, so you should have been free to enjoy your conversation.”

“Need fountain,” I wrote.

“You need education,” Sokrates said.

I underlined where I had written that the fountain was needed, and added “more.”

As I did that, Ikaros came out of the Ferraran hall and saw us. “Well, what’s this?” he asked. “I was about to go seeking you, Sokrates, and here you are sitting in the sunshine with a baby and a Worker.”

“Yes, I’m being lazy and indulging myself,” Sokrates said, smiling up at Ikaros.

“I don’t believe you. I think you’re engaged in one of your enquiries into some subject and you didn’t mean to include me!”

Ikaros sat down beside Sokrates. The baby cooed at him and kicked up her feet. “Ooooh!” she said.

“On the contrary, I’m delighted to have you join us. We were considering the ethics of need. Crocus believes that the birthing house of Ferrara needed their latrine fountain mended more urgently than he needed his leisure time for education.”

I underlined “more.”

“Only more?” Sokrates asked. “Not more urgently?”

“I think he’s expressing hierarchies of need,” Ikaros said. “He thinks the women need their latrine fountain more than he needs his conversation.”

“Why do they?” Sokrates asked.

“Plumbing important,” I wrote.

“Why?” Sokrates asked.

It was axiomatic. I had a hierarchy of priorities in my memory, and among those plumbing ranked extremely high, immediately below electricity. I had no idea why. I inscribed a question mark.

Then the baby kicked her legs again and emitted a stream of yellowish liquid into Sokrates’s lap. Sokrates and Ikaros laughed, and Sokrates called into the house for an attendant to take the baby. He took off his wet kiton, dropped it in a heap, and sat down again naked. The attendant took the baby back inside.

“That’s her contribution to the argument, and a practical demonstration of why plumbing is important,” Ikaros said, still laughing.

“Nonsense,” Sokrates said. “I never saw this kind of plumbing until I came here. We managed in Athens with wells for drinking water, a drain down the middle of the street for waste, and we cleaned ourselves with oil and brass scrapers.”

“The wash fountains and latrine fountains here are better than we had where I come from too,” Ikaros admitted.

“How demonstrate plumbing?” I asked, completely perplexed.