 Why does Infield don a lightning rod at the beginning of the story?
Henry Infield placed the insulated circlet on his head gently. The gleaming rod extended above his head about a foot, the wires from it leading down into his collar, along his spine and finally out his pants leg to a short metallic strap that dragged on the floor. Infield turned his soft blue eyes to the black and tan oxfords with the very thick rubber soles. "I dunno, Henry, but staying on our side is a pretty good way to keep sane Floating before him in memory was the vertical hoop and the horizontal hoop, both of shining steel-impervium alloy. The gyro actually passed over a man's shoulder, through his legs, under his arms. Infield stepped into the main stream of human traffic and tried to adjust to the second change in the air. A young man with black glasses and a radar headset (a photophobe) was unable to keep from being pushed against Infield. It was the first time in years that anyone had apologized to Infield for anything. A clean-cut young man with mouse-colored hair was moving toward the stubble-chinned, heavy-shouldered man quivering in the center of a web of impervium cables stuck secure to the walls and windows of buildings facing the street, the sidewalk, a mailbox, the lamp post and Infield. Mouse-hair yelled hoarsely, "Uncouple it, Davies! The magnetic suction dart dropped away from Infield like a thing that had been alive and now was killed. Mouse-hair drove a fast, hard right into the soft blue flesh of Davies' chin.
 He wants to know what it feels like to be a Cured, and therefore he pretends to have a fear of thunder.
 He wants to infiltrate the fraternal club for the Cured in order to prevent Price's authoritarian rule, so he must blend in.  It will protect him against lightning strikes and is meant as a Cure for his astraphobia.  He wants to know what it feels like to be a Cured, and therefore he pretends to have a fear of thunder.  He is tired of working as a psychiatrist at Infield & Morgan and wants to seek out new opportunities in the world of the Cured.