Hunter S. Thompson pioneered a style of journalism called “gonzo journalism,” a highly subjective and immersive basis of reporting where the journalist becomes a central part of the story, often using unconventional and exaggerated techniques to convey the experience. In this interview, his talks about his ideas for “Fear and Loathing in Las Vegas,” “Hell’s Angels: The Strange and Terrible Saga of the Outlaw Motorcycle Gangs,” which explored the notorious motorcycle gang, and “Fear and Loathing on the Campaign Trail ’72,” a chronicle of the 1972 U.S. presidential campaign.