Stamets has been a devoted acolyte, emissary, and evangelist of the fungi for more than four decades. Early on, he recognized that they were far more than forbidden fruits or culinary ingredients. To him, they and the mycelium—the hidden, subterranean networks of filaments—from which they spring (and which he’s dubbed “Earth’s natural Internet”) are powerful gifts of nature that hold the secrets to curing a multitude of medical and environmental ills. He’s made it his mission to not just uncover those secrets, but to dispatch the blindness and prejudices humans have toward mushrooms—what he calls “mycophobia”—that keep people from understanding how crucial these humble organisms underfoot are to our survival.