Usually, discussions about the compatibility of content externalism with self-knowledge focus on our knowledge of content. I look at externalist consequences for our knowledge of our own attitude-types. I show that there is a certain kind of mistake about the nature of one's own attitudes which would not be possible if externalism were false. While this does not cause trouble for externalism in general, it does cause trouble for some externalists' explanations of the compatibility of externalism with self-knowledge. I end with a picture of our knowledge of the attitudes that is compatible with externalism.