A white Ford pickup truck broke through a thick curtain of fog one morning in February, winding its way down a muddy farm road in California’s Central Valley. From it emerged a 64-year-old dairyman, burly and tan, who left the engine running as he lumbered toward me with open arms. “You must be Mark,” I said, warning him I wasn’t one for hugging. “I’m a hugger,” he said, pulling me in anyway.