The Marriage of the Sun and the Moon.
Excerpt from Dr, Andrew Weil’s book Publisher in 1980:

I knew that Latin America would be a rich source of information. Therefore, I went to Mexico to learn Spanish. Once in Mexico, I quickly abandoned my plan to take formal language classes in Cuernavaca and settled instead in the nearby village of Tepoztlán. There I became one of the first students in a new, experimental school called the Colegio de Tepoztlán, under the direction of Marco Polonsky, an offbeat teacher and unforgettable character.

Marco’s philosophy of learning languages was out of the ordinary but struck me as correct. He said that we all had the capacity to learn languages, since we did it as infants, that it had nothing to do with intellect but rather was an operation of the unconscious mind. The only abilities it depended upon were accurate listening and accurate imitating. Therefore, the way to learn a new language is to want to learn it badly and immerse yourself in it, letting as much of it flow into the unconscious mind as possible. Whether you understand it or not is irrelevant. Forget about grammar books and formal instruction, Marco said. Just listen and imitate.

Classes were bizarre. Sometimes Marco would have us fall into trance states to the accompaniment of recorded chamber music while he intoned vocabulary words from a Spanish comic book. When pressed for more-structured help, he would decline, saying that there was no way to teach another person a language.

He did arrange for us to be apprenticed to local people to force us to talk. I was placed in the care of the village carpenter and spent many pleasant afternoons with him in an outdoor shop, helping to make furniture.

I must say that the Polonsky method worked like a charm. In three months I was speaking passable Spanish and three months after that I was speaking good Spanish. The only other language I ever learned as well was German, and that took four years of painful work in high school. I would never again attempt to learn a language by studying it and I have no doubt that I can learn any language now just by really wanting to and placing myself in the right part of the world.