From the living room, Meemaw’s voice drifted in. She was watching a soap opera. "Shoot the trolley's tires. Problem solved."

Mary turned from the stove, a flour-dusted hand on her hip. "You pray. You ask God to stop the trolley."

George Sr., home early after failing to fix the Zenith, grunted. "Pull the lever."

The autumn light over Medford, Texas, was the color of weak tea, filtering through the blinds of room 207 at East Texas Tech. Sheldon Cooper, age fourteen and already a terror in the physics department, sat rigidly in a wooden chair that was, in his estimation, designed by a sadist. The plastic strip along the back edge dug into his spine.

The class laughed. Dawkins wrote something in his grade book. Sheldon suspected it was not a compliment.