Timothy Francis Leary was an American psychologist and author known for strongly advocating psychedelic drugs. Evaluations of Leary are polarized, ranging from "bold oracle" to "publicity hound". According to poet Allen Ginsberg, he was "a hero of American consciousness", while writer Tom Robbins called him a "brave neuronaut". President Richard Nixon disagreed, calling Leary "the most dangerous man in America". During the 1960s and 1970s, at the height of the counterculture movement, Leary was arrested 36 times.