A number of philosophical doctrines developed as responses to some mainstream views of the Iberian colonial period (roughly, from the late 1500s to the early 1800s). Chapter 1 of this book looks closely at four such doctrines whose central themes concerning Latin America can be traced to that period. It first examines the ideas of three Spanish thinkers, Bartolomé de las Casas (1474-1566), Francisco de Vitoria (1486-1546), and José de Acosta (ca. 1539-1600). The chapter demonstrates that Las Casas and Vitoria were set to determine the moral status of the Spanish conquest, and developed novel doctrines of practical ethics and political philosophy. Acosta raised empiricist objections to Scholasticism in epistemology and philosophy of science. Pressured by the new physical and social realities of the Americas, these three thinkers were among the early challengers of Thomism as interpreted in the Spanish world during the sixteenth century. But the chapter also examines what Edmundo O’Gorman (Mexican, 1906-1995) argued more recently against the myth of Columbus’ “discovery” of America. Clearly, the end of the colonial period was far from marking the end of reflection on philosophically interesting aspects of the Iberian expansion.