Preston stood up suddenly. His chair rolled back and hit the brick wall.

“This is about Saturday,” he said. “This is revenge. Because we made a couple of jokes at dinner.”

I looked at him for a long time.

“No, Preston,” I said. “If you'd been the kindest man at that table on Saturday, the answer would be exactly the same. Your app gives kids answers instead of understanding. And it's built on lessons you took from teachers without asking.”

I stood up too.

“The only difference Saturday made,” I said, “is that now I know you'd have said all of this to my face anyway. You just didn't know whose face it was.”

He didn't have anything to say to that.

His co-founder picked up the laptop.

“I need to think about some things,” the young man said quietly. He looked at me. “Ms. Holloway, I'm really sorry. I didn't know about the videos. My little sister uses BrightPath. She loves her tutor.”

“What's her tutor's name?”

“Mr. Peters. Math. Tuesdays.”

“David Peters,” I said. “He's wonderful. Tell her to keep going.”

The young man nodded and left.

Preston stood alone at the window. Then he followed him out.

He didn't say goodbye.