Kant’s essays in the philosophy of history, such as Universal History and Conjectural Beginning , offer a speculative account of the gradual development of reason in our species and of the way the mature use of reason can be attained. Such mature use of reason, as Kant explains a few years later in the published Anthropology , is characterized by abandoning the standpoint of “practical egoism” and learning how to exercise the psychological disposition to “pluralism”. To be a pluralist, he claims, means to be capable of seeing things from other people’s standpoints, of giving deliberative weight to the needs of others, and of taking part in universally valid judgments. But Kant is never explicit about what is required in order to become a pluralist, nor does he explain what it means to be a pluralist beyond a brief remark in the Anthropology. My paper takes a detailed look at this under-studied notion and offers a novel account of this notion. I explicate the features of pluralistic thinking and I connect this notion to the public use of reason, the three maxims of common human understanding, and the role played by interpersonal communication in advancing the progress of our rational capacities. I also explain the key role of education in reason’s development and the conceptual relationship between the enlightenment of an individual and the enlightenment of the human species.