The Tenkalai-Vadakalai division described elsewhere in this collection is a later development; neither school claims that Ramanuja himself resolved the question its two positions later disputed, and both trace their authority to the same eleventh and twelfth century teacher, reading his synthesis in different directions.
Ramanuja, the principal systematizer of Vishishtadvaita, "qualified non-dualism", taught that the individual soul and the material world are real and related to the supreme God, Vishnu-Narayana, as a body is related to its indwelling soul, dependent and inseparable, while remaining genuinely distinct from it, a position framed against the Advaita teaching that self and ultimate reality are simply one and that the world's multiplicity is a form of ignorance.
Within this framework Ramanuja taught prapatti, surrender to God, as a valid and complete path to liberation alongside the older triad of karma, jnana and bhakti, but his own writings do not settle with technical precision how much the devotee contributes to that surrender and how much is purely divine initiative, the very question later commentators split over. His successors developed the implications of his teaching along the two lines that hardened into the cat and monkey schools only in the centuries after his death, chiefly among teachers active at Srirangam, the tradition's most important temple center.
The retrospective character of the split is philosophically significant: both schools present themselves as the correct unfolding of Ramanuja's own position rather than as a departure from it, which is why the disagreement has persisted as an internal argument about interpretation rather than a division between two independently founded traditions.