If Vaishnavism is so popular and wide spread in India, the credit must go to Sri Ramanuja, who took advantage of the ecstatic outpouring of the south Indian mystics, the Alvars, and produced a highly logical philosophy of knowledge soaked in devotion as the easiest means of God-realization.
Learning and wisdom are superfluities, the surface glitter merely, but it is the heart that is the seat of all power. It is not in the brain but in the heart that the Atman, possessed of knowledge, power, and activity, has its seat.
-Swami Vivekananda