The Categorical Imperative is supposed to provide a way for us to evaluate moral actions and to make moral judgments. It is not a command to perform specific actions -- it does not say, follow the 10 commandments, or respect your elders.
A blurb on a book can be any combination of quotes from the work, the author, the publisher, reviewers or fans, a summary of the plot, a biography of the author or simply claims about the importance of the work.
a brief advertisement or announcement, especially a laudatory one: She wrote a good blurb for her friend's novel. verb (used with object) 2. to advertise or praise in the manner of a blurb. Origin of blurb.