Spain conquered the seas, found a new world and different realities than the one known in Europe. But a question needed to be answered with what they found in those new territories: do the Indians have souls? The Church, bound to protect and convert the natives and the conquerors who treated them like slaves and thought they were only merchandising, expose their arguments and reasonings at what would be known as the Vallidolid controversy. Between them, there's a cardinal hearing both parts and trying to get reasonable answers from this critical question.