I was taking LSD periodically, every couple of months. I was in a strange state of mind, influenced by these visions. ... I was trying to draw it in my sketchbook, and that began to coalesce into these comic strips that were stylistically based on grotesque, vulgar humor comics of the thirties and forties. ... All of those characters came out of that crazy visionary period that I couldn't shut off. It was spontaneous, but I was so crazy, I was really out of my mind, it was like schizophrenia. It was like what produces art by crazy people in a madhouse. Anything could be an influence, anything I heard. I was in Chicago in early '66 and the radio was on, there was some tune playing, it was a black station, and this announcer said, That was Mr. Natural. I just started drawing Mr. Natural, this bearded guru-type character in my sketchbook, it just came out.