Conversation is an important concept; it is Appiah’s model and method for cosmopolitan ethics. He uses the term in several ways. In the Introduction, he emphasizes that conversation is as simple as the need to coexist in a community: “conversation in its older meaning, of living together, association” (xix). He also views conversation (especially across boundaries) as intentionally seeking common ground with another, perhaps to attempt to convince them of our point of view, or only to learn from exposure to their point of view. This can be “literal talk,” but it can also be “a metaphor for engagement with the experience and the idea of others” (85). He does not see conversation as necessarily leading to agreement; he believes “it’s enough that it helps people get used to one another” (85).

Contamination is the mixing, borrowing, and hybridization of distinct cultural practices. Appiah sees contamination as inevitable and ultimately positive, a potential “counter-ideal” for those who want to preserve cultures, who admire “the authentic culture of the Asante or the American family farm” (111). Contamination among cultures has happened throughout world history and occurs anywhere different cultures have contact with one another.