Appiah distinguishes three distinct forms that what we call “racism” can take. Racialism is the empirical proposition that there are racial essences—unique sets of physical or psychological traits possessed by one racial group and not shared by others. Appiah argues that racialism, though false, is nevertheless, in and of itself, morally neutral. But he adds that it is commonly presupposed by extrinsic racism, which justifies racial discrimination by appeal to alleged moral or intellectual differences between races, and by intrinsic racism, which assigns a greater value to one race simply because of the bare fact of which race they belong to. The common thread of racialism underlying both other forms of racism makes it dangerous in practice.
Appiah notes that extrinsic racism rests on theoretical or intellectual errors, whereas intrinsic racism, being less responsive to reason and evidence, is essentially a moral error. He concludes with some remarks about how these diverse forms of racism, and the essentially ideological racial prejudice to which they are related, can be understood and addressed in our public life, where such errors pose a grave threat to vulnerable groups.