The tone of the book is conspiratorial. There is always the sense that the narrator and the reader are a bit more clever than most of the characters. One example is in Chapter 16, when the Wizard of Oz gives the Cowardly Lion a vial of "courage" to drink:
‘What is it?’ asked the Lion. ‘Well,’ answered Oz, ‘if it were inside of you, it would be courage. You know, of course, that courage is always inside one; so that this really cannot be called courage until you have swallowed it. Therefore I advise you to drink it as soon as possible.’
Oz is in on the conspiracy with the narrator and reader in this moment. The Lion has spent the entire book searching for courage, yet the reader has seen example after example of the Lion acting quite courageously despite considering himself "cowardly." Part of the Lion's confusion seems to be that he thinks being afraid makes him cowardly, no matter what his actions are. But the Lion regularly pushes through his fear to save his friends from dangerous situations, which by many accounts is the very definition of courage. Oz sees what the narrator and reader have known all along: the Lion needs to redefine courage and recognize it within himself. Oz tells the Lion that the vial of mysterious liquid will turn into courage once he has swallowed it. The Lion does not realize, as the narrator and reader do, that Oz is describing the placebo effect. The Lion simply needs to believe he is courageous, just as the Tin Woodman needed to believe he had a heart, and the Scarecrow needed to believe he had a brain.
Baum does not directly spell out this moral, but he comes close enough that it is next-to-impossible for even young readers to miss what the Lion still doesn't understand. By letting the reader remain smarter than some of the characters, Baum encourages excitement over the lessons the book is trying to teach. Rather than preaching to readers, Baum lets them feel clever to understand what the characters do not.
