Singer-songwriter John Denver, who was always seeking, never quite finding, was a proponent of the controversial self-help movement, the Erhard Seminar Training. When Denver substituted for vacationing host Johnny Carson on the Tonight Show in 1973, it was natural that he would invite the man behind the verbally abusive est workshops, Werner Erhard.

The footage is shaky and black-and-white, but worth watching. Oh, and that’s puppeteer Shari Lewis of Lamb Chop fame to Erhard’s right.

Suzanne Snider recalls the origins of est in a 2003 Believer magazine:

“Born John Paul Rosenberg in 1935, Werner Erhard changed his name in 1960 and left his wife and three children in Philadelphia to fly West with his mistress June Bryde. The two cobbled together a conspicuously Teutonic moniker for the nice Jewish boy from Pennsylvania (inspired by two different people—German finance minister Ludwig Erhard and atomic scientist Werner Heisenberg—both mentioned in an in-flight article on Germany’s economic recovery). Erhard resumed his career in sales when he reached San Francisco, working for Encyclopedia Britannica, Parents magazine, and Great Books, while experiencing a wide range of what the Human Potential Movement had to offer: Gestalt therapy, Zen Buddhism, Mind Dynamics, Dale Carnegie, Scientology, and a book by Napoleon Hill called Think and Grow Rich. In 1971, Erhard had his infamous epiphany while driving over the Golden Gate Bridge. He said in his biography, ‘…after I realized that I knew nothing—I realized that I knew everything… everything was just the way that it is, and that I was already all right… I realized I was not my motions or thoughts. I was not my ideas, my intellect, my perceptions, my beliefs…I became Self.’ His revelation became the basis for est workshops, his shrewdest business scheme to date.

Erhard’s new view on life, which treads a fine line between Zen Buddhism and mild psychosis, would appear a hard sell. It wasn’t lucid on an intellectual level, if at all, and other parties would have to comprehend it through means, admittedly, other than reason and logic. Nonetheless, est (which stands for Erhard Seminars Training, and also means ‘it is’ in Latin) began in the ballroom of the Jack Tar Hotel in San Francisco, and became the singularly most influential group to emerge from the Human Potential Movement. Understandably, this strange new program, consisting of heady imagery, emotional confessions, est-specific jargon (‘racket,’ ‘asshole,’ ‘barrier’) and aphorisms (‘I know that you know that I love you, what I want you to know is that I know you love me’ or ‘If God told you exactly what it was you were to do, you would be happy doing it no matter what it was. What you’re doing is what God wants you to do. Be happy.’), captured the imagination of men and women across the United States. Between 1971 and 1984, 700,000 people enrolled in the est workshop to ‘get it.’ Participants who approached their est workshops and the elusive ‘it’ with good sense and literalism were rebuffed. One est trainer responded to a participant’s thoughts with ‘Don’t give me your goddamn belief system, you dumb motherfucker.'”