One of the most striking features of Amazonian mestizo shamanism is the icaro, the magic song, whispered, whistled, and sung. The shaman uses icaros to call the spirits for healing, protection, or attack, and for many other purposes as well — to control the visions of another person who has drunk ayahuasca, work love magic, call the spirits of dead shamans, control the weather, ward off snakes, visit distant planets, work sorcery.

It is universally said that each shaman learns his or her own icaros from the spirits themselves; indeed, the poet César Calvo Soriano calls them “untransferable magic songs.” But there are exceptions. First, icaros can be learned from one’s maestro ayahuasquero. My teacher doña María Tuesta told me that I should first learn the icaros of don Roberto Acho, my maestro ayahuasquero; as time passed, she said, and I continued to diet with the plants, I would learn icaros of my own.

And icaros can be learned from other shamans. Indeed, there are many stories of shamans traveling long distances to learns specific icaros. Anthropologist Françoise Barbira-Freedman reports that one of the Lamista Indian shamans with whom she worked traveled from San Martín to the Ucayali to learn the icaro del kapukiri.

Some shamans even visit other shamans incognito in order to steal their icaros. That is why many shamans mumble their songs, or sing in many different languages; the goal is to make their songs hard to learn, to keep them from being stolen. Doña María frequently compared her own open-handedness with the stinginess of other shamans, who do not want to reveal their icaros. “I’m not selfish,” doña María told me. “I sing loud because I’m not afraid to let people know what I know.”

But one’s own icaros most frequently come while dieting with the plants and other substances, in ayahuasca visions, in dreams, in the unheard rhythms of one’s own heart. It is a process that people find hard to describe, especially when the songs are in strange or incomprehensible languages. Musician Alonso del Río, who apprenticed for three years with renowned Shipibo shaman don Beníto Arévalo, talks about this phenomenon. “It doesn’t go through the mind,” he says, “but between one spirit and another.” It has something to do, I think, with solitude. “While you are alone with the sounds of the jungle and its animals,” says Cocama shaman don Juan Curico, “it is a real concert, a choir, that is the silence of the jungle.”

The icaros arrive in various ways. Don Solón Tello Lozano, a mestizo shaman in Iquitos, says, simply, “The plant talks to you, it teaches you to sing.” One may hear the icaro externally, as if sung by someone else, or one may hear it inwardly. Both words and melody may come together, or first one and then the other. One may hear only the words and then complete the melody oneself. Don Agustin Rivas says that he would make a song for each plant he dieted with as its power entered him, with the melodies coming first and the words added later; indeed, the lyrics of some of his icaros were written by Faustino Espinosa, a professor of Quechua. Sometimes, as with don Francisco Montes Shuña, a spirit whistles and sings the melody of the icaro in a dream. Sometimes there is simply an overwhelming urge to sing, and the song and melody come out by themselves.

Three days after Pablo Amaringo had undergone a healing, he was astonished to find himself singing, perfectly, the icaros he had heard there, including the words. “I sang many icaros,” he says, “as if the song were in my ears and on my tongue.”

The third time doña María drank ayahuasca, the spirit of ayahuasca entered into her, and she began to sing loudly. El doctor ayahuasca was in her body, she told me, singing to her, and ayahuasca appeared to her as two genios, spirits, one male and one female, who stood on either side of her — a woman dressed in beautiful clothing, wearing jewelry made of huayruru beads, “everything of the selva, the jungle,” and an ugly man, with bad teeth. Everyone in the room became very quiet, she said, as she sang her new icaro de ayahuasca.