Four principles
According to the account given in Vera Fróes and Marco Imperial's book Santo Daime: Cultura Amazônica, the doctrine's four basic principles — Harmonia, Amor, Verdade, and Justiça — trace back to teachings Mestre Irineu received through his affiliation with the Círculo Esotérico da Comunhão do Pensamento (Esoteric Circle of the Communion of Thought), a group headquartered in São Paulo. Mestre Irineu is recorded as receiving honors and certificates from that organization in 1955.
A later affiliation
Some years afterward, Mestre Irineu also joined the Rosicrucian Order (Ordem Rosacruz), an older esoteric and mystical tradition. Santo Daime doctrine treats the four principles as a foundation running through its teaching and ritual, with each explored as its own subject within the tradition.