In the novel The Outsiders, what does Pony mean when he says "I was supposed to be the deep one"?

While Ponyboy and Johnny are hiding out, they begin to read the novel Gone With the Wind. Pony mentions that Johnny really enjoyed the book but didn't know much information about the Civil War or the setting of the novel. After Ponyboy explains the historical context and background, he says that he is amazed at Johnny's ability to comprehend deeper meanings throughout the story. Ponyboy then comments, "I was supposed to be the deep one" (Hinton 65). Ponyboy has a reputation of being one the of most intelligent individuals in the Greaser gang. He consistently gets good grades and is an avid reader. In contrast, Johnny never excelled at school, which is why Ponyboy is rather surprised at his ability to grasp deeper meaning in the text and made the previous comment about how he was supposed to be the “deep one." Johnny is not considered intelligent in the traditional sense simply because he has a hard time keeping pace with the lessons at school and gets bad grades. Given an adequate amount of time and opportunity to understand certain concepts, Johnny can express his innate ability to comprehend deeper meanings and messages throughout various texts.