 Soto once considered going to the New World to resolve the controversies there. Unable to go himself, he advocated sending good missionaries. In addition, his writings were employed by the Third Mexican Council (1585) in the preparation of a confessors’ manual geared to a world of both Hispanic and Amerindian residents (Poole [ed.] 2018). Soto’s relectio on dominion concluded that Spain’s title to the Indies was hard to justify. He rejected the opinion of Sepúlveda on the justice of waging war on infidels, also Pope Alexander VI’s division of overseas domains between Spain and Portugal. Soto was trusted by all participants in the Junta of Valladolid to summarize the conflicting opinions of Las Casas and Sepúlveda, though he, or perhaps Cano, another critic of conquest, may have been the one person who, according to Sepúlveda, opposed him. The Dominicans of Salamanca continued to argue for just conduct by Spaniards in their overseas dominions; and also Jesuits like Molina, even in their defense of slavery and slave trade, did not refer to the concept of slaves by nature. Soto, though accepting slavery, rejected the idea of natural slavery: in his view, human beings who were incapable of leading their own lives clearly had to be guided by wiser men, but for reasons of their own well-being, not as living tools in the Aristotelian sense. So, slavery for him was merely conventional.