On the way back down to the Valley, we'd been talking about – debating – the home screen issue in the product interface when David suddenly fell silent.
"What's up?"
No reply. He shifted in the driver's seat, staring straight ahead with a vaguely pained expression.
"Hey," I insisted.
"The windmills," he stated hollowly.
"What?"
"There are windmills on that hill."
I peered through the darkness toward the indistinguishable horizon. Frankly, I could not see a thing.
"Really. So?"
"Windmills spinning in the dark make me uncomfortable," he muttered.
I scrutinized his face. The light from oncoming traffic produced a greenish pallor.
"Really?"
"One day–" He gulped nauseously. "One day, I was driving back to Berkeley from San Jose. I started feeling weird. Pulled over and puked out my guts."
"Jesus."
"I had a migraine the rest of the night. Trembling and sweating. I went to the doctor the next day. He ruled out food poisoning, the flu."
"Yeah?"
"He asked me where I'd been, what I'd seen. What I hadn't seen."
"And?"
"He determined that the presence of windmills along the highway, spinning in the–" he shuddered in disgust – "dark had made me sick."
"How is that even a thing that can happen?" I asked.
David shrugged. "There's lots of people like me. It's an environmental sensitivity."
"How about windmills in the daytime?"
"Not a problem."
"What is it about them, do you think, at night?"
He sighed and answered through clenched teeth. "It's dark. They're spinning. They're spinning in the dark. I don't know what else to say."
"All right."
"It's awful, I'm telling you. Awful."
"Want me to drive?"
"Could you?"